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- - - - Land plants - before 600 mya
      - Seed plant - 350 mya
      - Flowering plant - 150 mya
      - They arrived in a terrestrial environment. We may have had these plants around the Jurassic time period
      - all plants have a similar structure, so we refer to them as Multicellular Photosynthetic organisms that live on land (generally)
      - Photosynthesis - 3.5 bya
  - - - He associated all plant life with a tree
      - Here is a modern day tree of life Based on similarity of ribosomes and history of life microbial
  - - - Proton Motive Force
      - ATP #
      - Glycolysis (cyclic)
        
        Major steps
        
        Carbon Molecules
        
        During conversion, energy is stored (two ATP per glucose) reducing equivalents are formed (two NADH per glucose
        
        Widespread metabolic pathway that converts the six-carbon sugar glucose into a series of ten reactions into the three-carbon sugar pyruvate
        
        Embden-Meyerhof- Parn pathway; pathway that produces pyruvate
        
        Carbon Fixation
        
        Likely began with chemosynthesizers
        
        Living around ancient volcanic vents
        
        Variation among bacteria on how sugars are synthesized
        
        Only organisms which can use external energy source able to manufacture own carbohydrate fuel
        
        Standardized in later lineages
        
        Described by the Calvin-Benson- Bassham cycle
        
        Form used by plants
      - Fermentation
        
        NADH recycled to NAD+
        Leads to lactic acid or ethanol
        
        Glucose Monomer
        
        Glucose Isomers #
        
        Same formula
        
        C6H12O6
        
        Different biological roles
        
        Alpha: energy storage
        
        Beta: structure
        
        Starch
        
        Amylose
        
        Alpha 1,4 bonds
        
        angular
        
        Amylopectin
        
        Alpha 1,6 bonds
        
        linear
      - Reverse TCA #
        
        Aka reductive citric acid cycle
        
        Some bacteria use to synthesize C compounds
        
        Some steps can be catalyzed by minerals through photochemistry
        
        Precursor to stromal reactions of photosynthesis in plants
    - - Evolved under low oxygen
        
        ~2.7 bya cyanobacteria used H2O as electron donor
        
        Oxygen remained low for 2 billion years
        
        Carbon burial by plants
        
        Eukaryotes arose ~1.8bya so ~1.3 billion years in anaerobic conditions
  - - - Arose in a prebiotic soup containing most of necessary molecules
      - Growth & energy supply available
      - Early floating living world
      - Membrane bubbles
      - Containing information molecule
      - Perform limited # of metabolic reactions
      - Able to divide
      - Able to interact
      - Able to fuse
      - Fuse & share genomes & metabolic abilities
    - - Simple experiment
      - Dry and wet cycles
      - DNA + lipids
      - Sandwich to lipid vesicle with DNA inside
      - Suggest spontaneously formed
    - - Phospholipid
      - Micelle
      - Covered with protective wall in some organisms
      - Embedded proteins
      - facilitate metabolism
      - Receptors for functions such as self identify
      - Selection for Complexity
        
        Essential nutrients depleted
        
        Impose selection pressure
        
        Favored cells capable of
        
        Synthesizing limited molecules
        
        Origin basic metabolic pathways
        
        Those less dependent on exogenous sources of nutrients
        
        Eukaryotic Origins
        #
        
        Beta Glucose
        
        Monosaccharide
        
        Change in hydroxyl group at C1
        
        Distinguishes from 𝜶-glucose
        
        Important for biological activity
        
        Major building block of cellulose
        
        Cellulose Microfibrils
        
        Made of glucose monomers
        
        𝛃1,4-glucose bonds
        
        Through dehydration synthesis
        
        Hydrogen bonds make cellulose extremely strong
        
        Very few organisms have the capacity to break/digest cellulose
        
        Fiber in our diets
        
        Cellulose Similarities
        
        Chitin
        
        Insect exoskeleton
        
        Keratin
        
        Hair
        
        Fingernails
      - Endomembrane System
        
        Continuous connected membrane
        
        Forming multiple organelles
        
        Plasma membrane
        
        Golgi body
        
        Endoplasmic reticulum
        
        Nuclear envelope
        
        Prokaryotes vs. Eukaryotes
        
        Membrane-bound genetic material
        
        Circular DNA vs chromosomes
        
        Genome size
        
        Cytoskeleton
        
        Ribosome size
        
        Cytoskeleton
        
        Microfilaments
        
        Important for vesicle movement near membrane
        
        Actin
        
        Intermediate filaments
        
        More permanent, fix things in place
        
        Dimers→ tetramers
        
        Microtubules
        
        trackway for long-range movement of transport vesicles
        
        𝛂&𝛃-tubulin
        
        The Theory
        
        Ancestral prokaryote
        
        Eats but does not digest aerobic bacterium
        
        Over time, the symbiosis becomes interdependence
        
        Mitochondrial containing eukaryote eats a photosynthetic cyanobacterium but does not digest it
        
        Over time become interdependent
        
        Exchanges DNA
        
        Evidence
        
        Have own circular DNA
        
        Similar in size to bacteria
        
        Self-replicate binary fission (independent of nucleus)
        
        Can only be made from pre-existing ones
        
        Ribosomes similar in size to bacteria (70s)
        
        Double membrane
        
        Plastids
        
        Chloroplasts: typically green plastids used for photosynthesis.
        
        Etioplasts are the precursors of chloroplasts
        
        Chromoplasts: coloured plastids for pigment synthesis and storage
        
        Leucoplasts: colourless plastids for monoterpene synthesis;
        
        Amyloplasts: for starch storage
        
        Elaioplasts: for storing fat
        
        Proteinoplasts: for storing and modifying protein
        
        Inheritance
        
        Mainly from egg parent
        
        Gymnosperms from sperm parent
        
        Chloroplast
        
        6 more items...
        
        mitochondrial structure
        
        Outer membrane
        
        Inner membrane
        
        Folded areas are cristae
        
        Location of oxidative phosphorylation
        
        Matrix
        
        Internal solution
        
        Location of the citric acid cycle
      - Primary Cell wall
        
        Layer of additional protection
        
        Create turgor pressure along with large central vacuole
        
        Composed primarily of
        
        Cellulose→𝛃-glucose
        
        Hemicellulose
        
        Pectin
        
        Remains somewhat flexible to permit growth
  - - - Uses the mitochondria to complete process
      - Continue to strip energy from pyruvate from glycolysis
      - Major steps
      - Glycolysis
      - Pyruvate oxidation
      - Citric acid cycle
      - Oxidative phosphorylation
    - - Respiration become more complex and more efficient over time
      - More specialized enzymes
      - Compartmentalization
    - - Start with glucose (C6)
      - Ends with pyruvate (C3)
      - 2 net ATP
      - 2 NADH
      - Pyruvate and NADH move into mitochondria
      - Pyruvate Oxidation
        
        Electrons stripped from pyruvate and given to NAD+
        
        Carbon dioxide broken off, C3 → C2
        
        Acetyl Coenzyme A
      - CAC
        
        Acetyl CoA (C2) joins to C4 → Citrate (C6)
        
        Strip off electrons and provide to NAD+→NADH
        
        Coupled to break off of CO2
        
        Substrate level phosphorylation
        
        Coupled to break off of CO2
        
        Strip off electrons and provide to FAD →FADH2
        
        Complete cycle to C4
      - Nicotinamide adenine dinucleotide (NAD)
        
        NAD+ oxidizing agent, accepting electrons
        
        NADH is the reduced form and can give up electrons
        
        Stronger proton motive force that FADH2
        
        Can be converted to NADP
        
        Vitamin Niacin helps to build
      - Flavin adenine dinucleotide (FAD)
        
        Strong oxidizing agent
        
        FAD is reduced to FADH2
        
        Weaker proton motive force compared to NADH
        
        Vitamin B2, riboflavin base for construction
      - Chemiosmotic, electrochemical gradient
        
        Proton motive force
        
        Trapped protons creates a battery
        
        Only way down concentration gradient is through special protein complex
        
        ATP synthase
        
        Drive synthesis of ATP
      - ATP Synthase
        
        Catalyzes formation of ATP from ADP + Pi
        
        Brilliant example of a molecular machine
        
        Driven by energy from electrochemical gradient across membranes
        
        Mitochondrial cristae
        
        Prokaryotic cell membranes
        
        Plant thylakoid membranes
        
        ETC
        
        Electron transport chain
        
        Builds up the proton motive force
        
        Regenerates electron carriers
        
        Mitochondrial ETC consists of 4 large protein complexes
        
        Major Steps
        
        Electrons dropped off by NADH & FADH2
        
        Electrons pass through ETC
        
        Protons are pumped across
        
        Oxygen is final electron acceptor
        
        Chemiosmotic electrochemical gradient runs ATP synthase
        
        Driving production of ATP
- - - - Tracheids
      - Annular thickenings
      - Cooksonia
      - Thought to be true tracheids
    - - Created towering forests during Carboniferous
      - Early vascular group
    - - Poikilohydric
      - water content changes with the moisture in the surrounding environment
      - Equilibrate water potential through environmental source
      - Water-storage extend
      - Stayed small to reduce demand for water
      - Live in perennially wet substrates (stream sides)
      - More derived homoiohydric
      - hydroids
        
        Bryophytes
        
        Water conducting cell
        
        No plasmodesmata (imperforate)
        
        Aid in refilling from cavitation
        
        Apomorphic trait (similar function but different origin) to true vascular tissue
        
        No lignin
      - Tracheary elements
        
        Die at maturity
        
        Thickened lignin walls
        
        Waterproofing
        
        Structural support
        
        Stepwise progression
        
        Partially thickened
        
        Rhynia
        
        Vascular tissue not lignified
        
        Lignified tracheids
        
        Horneophyton
        
        Annular cell wall
        
        Helical cell wall
        
        During Devonian,
        
        Increase in xylem content
        
        Increase in tracheid size
        
        Increase in tracheid reinforcement
        
        Early Trachieds
        
        Water transport only (no support)
        
        lignified
        
        Relatively long and wide
        
        Ferns
        
        Tracheids + vessel elements in rhizomes of some species
        
        Lycophytes
        
        Pit membranes
        
        True tracheids
        
        Lignified with ornamented walls
        
        Banded or pitted
        
        Evolved likely once
        
        Tracheophytes
        
        Function in both
        
        Water transport
        
        Support
        
        Tapered at ends
        
        rather narrow
        
        Vessel elements
        
        Angiosperms
        
        Homogenous pit membrane
        
        Large diameter
        
        Dead and maturity
        
        Open, digested end walls
        
        Pine tracheids
        
        Function in water movement & support
        
        Torus-margo pit membrane
        
        Move to prevent cavitation
        
        Gymnosperm vs Angiosperm
        
        Vessels can have greater
        
        maximum diameters
        
        Maximum lengths
        
        Vessel elements may be short but the vessel can be much longer
        
        yields greater conductivity in vessel elements
        
        Lowers the cost (construction & transpiration)
        
        Having vessels permits more fiber (hardwood vs softwood)
        
        Downside is greater cavitation risk
        
        Vessel element differentiation
        
        Apical meristem
        
        Vacuolization
        
        Elongation
        
        Secondary cell wall
        
        annular
        
        Helical
        
        Reticulate
        
        Porous
        
        Dead at maturity
        
        Tracheid vs Vessel element
        
        Pit membranes are absent in perforations of mature vessel elements
        
        Conductive area greater in end wall of vessel elements compared to lateral walls; tracheids are similar
        
        Perforation plate morphology different than lateral-wall pitting in vessel elements; tracheid endwall similar to lateral
        
        Vessel elements have a greater diameter than tracheids
        
        Vessel elements are shorter than tracheids
    - - Widespread in bryophytes
      - Specialized plasmodesmata in end walls
      - Alignment along longitudinal arrays of endoplasmic microtubules*
      - Plastids
      - Mitochondria
      - ER vesicles
      - Breakdown of tonoplast
      - Mix vacuolar & cytoplasmic contents
      - Rarely some species have nuclear breakdown
      - Features common to sieve cells
      - Sieve cells & albuminous cells
        
        Transport of
        
        Photosynthate
        
        Hormones
        
        Electric signals
        
        ac aka Strasburger cells
        
        Gymnosperms only these
        
        Earlier lineages with various types including transitional = sieve elements
        
        Sieve area pores narrow
        
        Uniform sieve areas
        
        Mostly on ends
        
        Lacks sieve plate
      - Sieve tube element features
        
        Sieve plate
        
        Area with many sieve pores
        
        Usually on end wall
        
        Many sieve tube elements together = sieve tube
        
        Primary cell wall
        
        Living protoplasts at maturity
        
        Few organelles (ER)
        
        Callose & callose plugs
        
        Sieve tube element & companion cell features
        
        Transport of
        
        Photosynthate
        
        Hormones
        
        Electric signals
        
        Sieve tube element
        
        Sieve plate
        
        Sieve pore
        
        Lateral sieve area
        
        P protein
        
        Plastid
        
        Smooth ER
        
        Mitochondria
        
        Companion cell
        
        Branched plasmodesmata
        
        Vacuole
        
        Nucleus
        
        mitochondria
        
        Plasmodesmata connections
        
        Sieve tube & companion cell from same mother cell
        
        Connected by a large quantity of plasmodesmata
        
        One pore in sieve tube area branched into many on companion cell side
        
        Phloem differentiation
        
        Cell wall thickened
        
        Cytoplasmic clearing
        
        No ribosomes
        
        Callose deposited around terminal plasmodesmata
        
        Nuclear break down
        
        Formation of sieve plate & pores
        
        Sieve tube contents
        
        P-proteins
        
        May help in plug pores in response to leakage
        
        Forisomes
        
        Legumes
        
        Plug pores
        
        Sieve element plastids
        
        Mitochondria
        
        Very few
        
        Endoplasmic reticulum
        
        Lost ribosomes
        
        Highly folded
    - - Root and shoot have different arrangements
      - Key features to Monocots and Eudicots
      - Monocot
      - Root with pith
      - Stem without pith
      - Eudicot
      - Root without pith
      - Stem with pith
      - Increasing complexity
        
        Complexity increased
        
        Stem diameter increased
        
        Plant height increased
        
        Led to compartmentalization
        
        Selected for a woody habit
        
        3 major stele types
        
        Protostele (~420Ma)
        
        Earliest
        
        Solid vascular strand
        
        Phloem surrounds xylem or interspersed
        
        Siphonostele (~407Ma)
        
        Ring of phloem, xylem, surrounding pith
        
        Eustele (~390Ma)
        
        Most complex
        
        Strands of phloem & xylem separated by parenchyma
        
        progymnosperms
        
        archs
        
        Based on xylem maturation
        
        Protoxylem
        
        1st xylem to mature
        
        Usually smaller in diameter
        
        Metaxylem
        
        Develops later
        
        Usually larger diameter cells
        
        Exarch
        
        Protoxylem outside metaxylem
        
        Eg protosteles
        
        Endarch
        
        Protoxylem in middle
        
        eg eusteles, atactosteles
        
        Mesarch
        
        Protoxylem surrounded by metaxylem
        
        eg siphonostele
        
        Lycophyte
        
        Protostele
        
        Most ancestral type of stem vasculature
        
        Exarch
        
        Ferns
        
        Siphonostele
        
        Xylem surrounded by phloem
        
        Endarch
        
        Monocotyledonae
        
        Atactostele
        
        Numerous vascular bundles scattered throughout stem
        
        No pith
        
        Vascular bundles often surrounded by sclerenchyma
        
        Bundle sheath
        
        Eudicotyledonae
        
        Eustele
        
        Phloem outside xylem
        
        Bundles separated by parenchyma
        
        Endarch
        
        Metaxylem outside protoxylem
        
        Vascular bundle supported by sclerenchyma, bundle cap
    - - Amount of water loss per carbon gained increased after Silurian
      - Carboniferous period greatly drained atmospheric CO2
      - Water demand is relatively high
      - Water transport system energetically efficient (don’t starve)
      - Minimal maintenance = cell death
      - Transport energy minimal
      - Water filtration close to soil access
      - Selection pressure for wood
        
        Increased competition for light selected for
        
        taller plants
        
        More developed tree canopies
        
        Higher rates of transpiration
        
        More xylem, wider xylem & longer conduits
        
        Likely evolved 5 times
        
        Loss of secondary growth
        
        Monocotyledonae
        
        Arborescent
        
        No secondary growth
        
        First tree
        
        Lepidondrids
        
        Carboniferous
        
        ~320mya
        
        Vascular cambium only divided internally
        
        Archaeopteris
        
        Devonian/Carboniferous
        
        Reproduced via spores
        
        Extant lineages
        
        Lycophytes
        
        Euphyllophyte
        
        Secondary growth
        
        Complex plant development
        
        Growth in girth
        
        Produce secondary
        
        xylem (wood)
        
        phloem (inner bark)
        
        Ground tissue (rays)
        
        Continuous circular ring growth
        
        Vascular cambium
        
        Fusiform initials
        
        Stem cells
        
        Xylem and phloem
        
        Fascicular cambium
        
        Ray initials
        
        Stem cells
        
        Ray cells
        
        Interfascicular cambium
        
        Periclinal division
        
        More xylem & phloem
        
        Anticlinal division
        
        Wider circle of vascular cambium
        
        Fusiform initials
        
        Periclinal division
        
        Anticlinal divisions
        
        Secondary tissues
        
        Secondary xylem
        
        Secondary phloem
        
        Parenchyma rays
        
        Divisions 3D
        
        Wood block
        
        Unique for each face
        
        Longitudinal
        
        Transverse
        
        Radial
        
        Initials
        
        Fusiform - longitudinal
        
        Ray - radial
        
        Annular rings
        
        Xylem secondary cell walls robust
        
        Phloem is crushed
        
        Ring width determined by season and environment
        
        Alternation of
        
        Early wood
        
        Late wood
        
        Early vs Late
        
        3 more items...
        
        Sapwood vs heartwood
        
        8 more items...
  - - - Lepidodendrales extinct
      - Dichotomous rooting system
      - Lateral stigmarian rootlets
      - Root hairs, mixed reports
      - Highly branched
      - Similar to roots
      - No chlorophyll
      - No stomata
      - Develop gravitropically
      - No root cap
      - Extant species lycophyte
      - Bifurcating
      - With root hairs
      - No quiescent center
    - - Rhynie chert, Zosterophyllophyta, Early Devonian
        Upright stem, prostrate stems, downward (rootlike) stems
    - - Early without root hairs
      - Intact epidermis covered root tip
      - Anticlinal divisions only
      - Devonian lycophyte Asteroxylon mackiei
      - Independent evolution of
      - Endodermis
      - Root cap
      - Root meristem
        
        Diversity of arrangement used to infer phylogeny
        
        Number of initial cells differs
        
        Similar genes across plant taxa
        
        Similar genes in shoot to root
      - Root types
        
        Primary root
        
        Derived from radicle
        
        Main root
        
        Mainly dominant in eudicots
        
        Mainly ephemeral in monocots
        
        Lateral roots
        
        Adventitious roots
        
        Derived from stems & leaves
        
        Dominant in monocots
        
        Seminal roots
        
        Derived from mesocotyl
        
        General root plan
        
        Highly differentiated multicellular axis
        
        Found only in sporophytes of vascular plants
        
        Functions
        
        Anchors plant body to substrate
        
        Absorbs water
        
        Absorbs dissolved minerals
        
        Common features
        
        Apical meristem & root cap
        
        Pericycle
        
        Endodermis
        
        Root hairs
        
        Cortex
        
        Root cap
        
        Evolved independently
        
        Lycophyte
        
        Euphyllophyte
        
        Protect underlying tissues
        
        Cells that slough off
        
        Secrete mucilage
        
        Apical meristem
        
        Quiescent center
        
        Rarely divides
        
        Backup plan
        
        Maintains initial cells
        
        Behind root cap
        
        Pericycle
        
        Pluripotent
        
        Initiation of lateral root development
        
        Just inside the endodermis
        
        Root hairs
        
        Single celled
        
        Major absorption of water and minerals
        
        Via osmosis from hypotonic soil solution to hypertonic cells
        
        Delicate
        
        Short-lived
        
        Cortex
        
        Large storage area
        
        Outermost layers may show
        
        Hypodermis
        
        Exodermis
        
        Casparian strip
        
        Suberized lamella
        
        Bound by endodermis and epidermis
        
        Endodermis
        
        Casparian strip
        
        Prevents apoplastic movement of water
        
        Forces water to move through cell membranes to be filtered
        
        Lycophytes
        
        Selaginella sp example
        
        No root cap
        
        No root hairs
        
        Monocot
        
        Diversity
        
        Pith in center
        
        Endodermis
        
        Surrounded by cortex
        
        Monocot details
        
        Epidermis
        
        Cortex
        
        Endodermis
        
        Casparian strip
        
        Pericycle
        
        Xylem
        
        Phloem
        
        Pith
        
        Eudicot
        
        5 more items...
  - - - Earliest evidence of true leaves
      - Lycophytes
      - microphylls/ lycophylls
      - Euphyllophytes
      - Independent evolution
    - - Indeterminate growth proceeded leaf development
      - Leaves initiated in regular patterns around stem
      - Optimize light interception for photosynthesis
      - Convergent evolution
        
        Leaves had at least 5 independent origins
        
        Liverwort gametophyte
        
        Moss gametophyte
        
        Lycophyte sporophyte
        
        Monilophyte sporophyte
        
        Spermatophyte sporophyte
        
        Varied leaf development
        
        Mitosis of a single cell
        
        Liverwort
        
        Moss
        
        Moss midvein cell layer
        
        Microphyll
        
        Lycophyte
        
        Mitosis of 2 epidermal cells
        
        Frond
        
        Monilophyte
        
        Mitosis of single apical cell
        
        Shoot like development
        
        Euphylls
        
        Seed plants
        
        Pool of recruited cells
        
        From flanks of multicellular shoot apical meristem
        
        Enation theory
        
        Lycophyte leaves
        
        Progressive elaboration of epidermal outgrowths
        
        Vascular strands entered later
        
        Fossils consistent
        
        Asteroxylon
        
        Living evidence
        
        Selaginella draussiana
        
        2 epidermal cells grow to form leaf pair
        
        Zimmerman telome theory
        
        Evolution of euphylls
        
        Overtopping
        
        Unequal branching (primary & side)
        
        Planation
        
        Flattening of axes into 2 dimensional
        
        Webbing
        
        Develop thin tissue between axes of branches
        
        Branches becomes veins
        
        Webbing becomes mesophyll
        
        By Devonian euphylls widespread
    - - Ground tissue
      - Specialized parenchyma
      - Contains chloroplasts
      - Main function is photosynthesis
      - Aerenchyma
        
        Ground tissue
        
        Specialized parenchyma
        
        Contains air spaces from cells being digested
        
        Main function permit gas-exchange
        
        Large air pockets for buoyancy in aquatic plants
      - Collenchyma
        
        Ground tissue
        
        Thickened primary cell walls
        
        Main function in flexible support
        
        Found in bundle sheath of veins in some species
        
        Vascular tissue
        
        Xylem
        
        Tracheids
        
        Water transport
        
        Phloem
        
        Sieve tube element/ sieve cells
        
        Companion cells/ albuminous cells
        
        Photosynthate transport
        
        In veins
        
        Epidermis
        
        Dermal tissue
        
        Epidermal cells
        
        Guard cells
        
        Often cutenized
        
        Main function in protecting the internal tissues
    - - Microphyll
      - Single vascular trace along center of blade
      - Vascular strand connects directly to stem
      - Mesophyll
      - Epidermis
      - Stomata
      - Monocot leaf
        
        Epidermis
        
        Adaxial (outer) & abaxial (towards stem)
        
        Covered by cuticle
        
        Contains stomata
        
        bulliform cells
        
        helpful for the rolling and unrolling
        
        Mesophyll
        
        Veins
        
        Surrounded by bundle sheaths
        
        Eudicot leaf
        
        Epidermis
        
        Dermal tissue
        
        Epidermal cells
        
        Guard cells
        
        Cuticle
        
        Upper & lower
        
        Mesophyll
        
        Palisade
        
        Photosynthesis
        
        Spongy
        
        Gas exchange
        
        Veins
        
        Bundle sheath cells
        
        Xylem on top phloem on bottom
  - - - Potential for water to react or move
      - Due it it’s polarity
      - Attracted to other substances
      - Lower potential when it’s surrounded by ions
      - Water potential
        
        Based on the free energy of water
        Water moves from less negative water potentials to areas of more negative water potentials
    - - Three components of water potential
      - ψ = ψp + ψπ + ψm
      - ψp = pressure potential:
      - effect that pressure has on ψ
      - If water is under pressure, both pressure potential and water potential increase.
      - ψπ = osmotic potential:
      - effect that solutes have on ψ
      - Adding solutes decreases water’s free energy, so ψπ is always negative.
      - ψm = matric potential:
      - adhesion to structures such as cell walls, membranes, and soil particles
      - Adhesion can only decrease water’s free energy, so ψm is always negative.
      - Pressure potential ψp
        
        Hydrostatic pressure exerted on water in a cell
        
        In turgid plant cells positive value
        
        Xylem cells negative pressure due to tension
        
        Water at atmospheric pressure has a pressure potential of zero
        
        Osmotic potential ψπ
        
        Difference between the solution and pure solvent resulted after adding solutes
        
        Matric potential
        
        Adhesion of water molecules to nondissolved structures
        
        Example, soil particles
        
        Always negative
        
        Significant only outside living systems in very dry soils
    - - Transpiration stream
      - Water movement from soil to atmosphere
      - Follows relatively high to low moisture level
      - From less negative to more negative water potential
      - Water evaporates out of open stomata to drier atmosphere, creating water potential differential
        
        Stomata open shortly after daybreak
        
        Close at times of stress
        
        Close at night
        
        Water potential gradient from mesophyll cells all the way back to xylem draws water from vein
        
        Open stomata
        
        Water evaporates from intercellular spaces
        
        Starts the domino effect of water potentials
        
        Water enters through root hair via osmosis due to hypotonic soil solution
        
        Water moves from hypotonic to hypertonic solutions
        Root hairs greatly increase surface area
        
        Water pases through endodermis, filtering solution, preventing embolism and foreign invaders
        
        Casparian strip of root endodermis
        
        Forces symplastic movement
        
        Embolism is an air pocket
        
        Completely makes tracheary element non functional
        
        Water pulled up stem under tension, in an unbroken column
        
        As H2O diffuses out of xylem in the leaves, cohesive forces pull H2O upward through the xylem, all the way from the roots.
        
        H2O in the uppermost tracheary elements must lift the weight of the entire H2O column.
        
        Tension is on these molecules, and consequently, the pressure potential is a negative number.
        
        Water remains unbroken due to cohesion of water molecules
        
        Cohesion due to water polarity
        Adhesion along cell walls helps to fight gravity
    - - Transport assimilate from areas where it’s made = sources
      - Materials moved to sinks
      - Actively growing areas
      - Storage areas
      - Assimilate/ photosynthate loaded into sieve tube elements with help of companion cells from source
        
        Sugars transported as sucrose
        
        Actively transported into sieve elements
        
        Decreases water potential of STE
        
        Increases osmotic concentration, decreases water potential in sieve tube
        
        Creates a water potential gradient between sieve tube elements and surrounding cells
        
        Water enters sieve tube from xylem due to water potential differential, creating turgor pressure
        
        Phloem is always close to xylem
        
        Xylem has a much higher water potential than phloem
        
        Water moves from less negative water potential to more negative water potential
        
        Photosynthate moves by bulk flow to nearest/ strongest sink and is unloaded
        
        Sucrose actively transported from sieve tube
        
        By companion cells
        
        Stored as starch
        
        Used in metabolism
        
        Aerobic respiration
- - - - Elkinsia polymorpha
      - 4-5 lobes fused basal third
      - ~360mya
      - Late Devonian (W. Virginia)
      - Pseudosporogonites quadrapartitus
    - - Lobate integuments
      - Free from nucellus/ megasporangium
      - Moresnetia zalesskyi
      - 8-10 lobes fused at chalaza and widely separated
      - ~360mya
      - Enclosed ovule
        
        Complete enclosure of megasporangium within integument
        
        Increased protection
        
        Desiccation
        
        Herbivory
        
        Stamnostoma huttonense
        
        352 mya
        
        Gnetopsiselliptica
        
        Ovule evolution
        
        Evolved from shoot apex
        
        Gymnosperm nucellus apex similar to shoot apex
        
        Similar genes
        
        Innovations
        
        Heterospory
        
        Protection
        
        Integuments
        
        Pollen capture
        
        Pollen chamber
        
        Micropyle
        
        Nucellus
    - - Evolution of the ovule
        
        Heterospory
        
        Megasporangium enclosed in integuments
        
        Retention of megaspores w/in megasporangium
        
        Reduction # of megasporocytes/ megasporangium to 1
        
        Survival of 1 megaspore
        
        Endosporic megagametophyte
        
        Modification of megasporangium apex for microspores or microgametophytes
        
        Embryo develop within megagametophyte
        
        Heterospory
        
        Megaspores
        
        Megagametophyte
        
        Microspores
        
        Microgametophyte
        
        Found in some non-seed plants
        
        Megasporangium enclosed in integuments
        
        First integument telomes
        Second integument phyllad origin
        
        Reduce # of megasporocytes/ megasporangium to 1
        
        Megasporocyte
        
        Megaspore mother cell
        
        Reduced to one per megasporangium rather than hundreds
        
        Survival of 1 megaspore
        
        Megasporocyte undergoes meiosis
        
        4 resulting daughter cells
        
        3 megaspores degenerate
        
        1 megaspore remains
        
        Retention of megaspores w/in megasporangium
        
        Reduced megaspores with other 3 aborted
        
        Large megaspore retained inside megasporangium
        
        Extra layer of protection
        
        Endosporic megagametophyte
        
        Megagametophyte retained inside megaspore wall
        
        Fertilization of egg occurs in wall
        
        Extra layer of protection
        
        Modification of megasporangium apex
        
        Pollen chamber
        
        Through programmed cell death
        
        Micropyle
        
        Embryo develop within megagametophyte
        
        Multicellular megagametophyte
        
        Egg retained
        
        After syngamy, embryo develops within
    - - Multicellular free
        
        Gametophyte dominant stage in early land plants
        Reduced over time
      - Antheridia
        
        Sperm development within antheridia
        Sperm rely on water for swimming to archegonia
        
        Flagellated sperm
        
        Swim from
        
        Pollen
        
        Microgametophyte
        
        Dispersal no longer requires water
        
        Exine prevents desiccation
        
        Some with air bladders
        
        Transport by wind
        
        Haustoria pollen tubes
        
        Tubes feeding on nucellus
        
        Provide nutrients to developing sperm
        
        Can be a lengthy process from pollination to fertilization
        
        Reduced
        
        Angiosperm, 3-celled
        
        Tube cell
        
        Generative cell
        
        Microspore within microsporangium
        
        Mitosis within microspore wall
        
        Endosporic male gametophyte = pollen grain
        
        Direct delivery
        
        Direct delivery of sperm to the megagametophyte
        
        Pollen tube
        
        Directed by synergids
        
        Feeds on nucellus (gymnosperm)
        
        Feeds on style (angiosperm)
    - - Gymnosperm
        
        Megasporangium is nutritious tissue = nucellus
        
        Nested doll
        
        Integument (1)
        
        Megaspore wall
        
        Megasporangium
        
        Archegonium
        
        Eggs
      - Example: Pine Ovule
        
        Ovule on megasporophyll
        
        1 microsporocyte
        
        Pollen chamber
        
        Nesting doll
        
        Integument
        
        Nucellus
        
        Megaspore wall
        
        Megagametophyte
        
        Archegonium
        
        Egg
      - Angiosperm ovule
        
        2 integuments
        
        Megasporangium = nucellus
        
        Megasporocyte reduced to one
        
        Megaspore reduced to one and retained
        
        Megagametophyte = egg sac
        
        Furniculum
        
        Example: Lily Ovule
        
        1 megasporocyte
        
        1 megaspore
        
        2 integuments
        
        Embryo sac = megagametophyte
        
        8 nucleate
        
        3 antipodals
        
        Sometimes nutritive
        
        2 polar
        
        Becomes endosperm
        
        2 synergids
        
        Guide pollen tube
        
        1 egg
        
        Eventual zygote
        
        Gymnosperm vs Angiosperm
        
        Both single megasporocyte
        
        Both single megaspore
        
        1 integument, 2 integuments
        
        Unique to Angiosperm
        
        Additional protection from ovary wall
        
        Double fertilization
    - - Advantages
        
        Increased independence from free water reproduction
        
        Enabled colonization of drier upland habitats
        
        Enabling advanced reproductive traits
        
        Pollination drops
        
        Embryo dormancy increase chance of offspring surviva
        
        Gymnosperm
        
        Pine example
        
        Some with fleshy outer layer (aril)
        
        Several cotyledons
        
        Integument becomes seed coat
        
        Double-fertilization
        
        Pollen tube grows down style
        
        Generative cell divides into 2 sperm
        
        Pollen tube ruptures inside synergid releasing sperm
        
        One sperm fuses with egg
        
        2n diploid
        
        Zygote
        
        One sperm fuses with polar nuclei
        
        3n triploid
        
        Endosperm
        
        Monocot
        
        One cotyledon = scutellum
        
        Large amount of endosperm
        
        Corn example
        
        Integuments become seed coat
        
        eudicot
        
        2 cotyledons
        
        Large amount of endosperm
        
        Integuments become seed coat
        
        Bean example
  - - - Based on molecular data
      - Bisexual
      - Radially symmetric
      - Multiple whorls of petals
      - Androecium
      - 2+ whorls of anthers
      - Gynoecium
      - 5+ carpels
    - - Archaefructus sinensis
      - Likely herbaceous
      - Likely aquatic
      - 124.6bya
    - - Amborellaceae
      - Amborella
      - Amborella trichopoda
      - New Caledonia
      - Dioecious
      - Male plants
      - Female plants
      - Shrub
    - - Flowers indefinite in number of parts →flowers have few parts that are definite in number
      - Floral axis shortened
      - Original spiral arrange no longer evident
      - Floral parts often fused
      - Ovary superior → inferior
      - Perianth has become differentiated in distinct calyx & corolla
      - Radial symmetry →irregularity
    - - Perfect, complete flower
        
        A flower is a stem with leaf-like structures.
        
        Complete flowers have all four floral appendages:
        
        Sepals, sterile
        
        Petals, sterile
        
        Stamens, male fx
        
        Carpels, female fx
        
        Incomplete flowers lack at least one appendage
      - Sepals
        
        Sepals are the outermost floral appendage.
        
        Are modified leaves that surround maturing flower parts.
        
        Protect the flower bud as it develops.
        
        May be colorful.
        
        All the sepals together are referred to as the calyx.
        
        Petals
        
        Petals are located above the sepals on the receptacle.
        
        Are leaf-like but contain pigments other than chlorophyll.
        
        Attract pollinators.
        
        Collectively are a corolla.
        
        Sepals and petals collectively are a perianth.
        
        Absent in wind-pollinated species.
        
        Stamens
        
        Stamens occur above the petals.
        
        Are collectively the androecium.
        
        Diploid anther cells (microsporocytes) undergo meiosis to produce four microspores.
        
        Microspores
        
        Undergo mitosis
        
        form a resistant cell wall
        
        Microgametophyte
        
        Pollen grains
        
        Carpels
        
        Megasporophyll
        
        Carpels, collectively, are the gynoecium.
        
        Stigma catches pollen grains.
        
        Style elevates the stigma.
        
        Ovary where megaspores are produced.
        
        After fertilization of the egg, ovules mature into seeds.
        
        Within the ovary are placentae bearing small structures called ovules
    - - Carpel position
        
        Whorls inserted relative to ovary
        
        Superior
        
        Carpel above
        
        Inferior
        
        Receptacle surrounds carpel
        
        Carpel below
        
        Perianth & stamen insertion
        
        Hypogynous
        
        Perianth & stamens on receptacle beneath ovary
        
        ex lilies
        
        Epigynous
        
        Perianth & stamens from top of ovary
        
        ex apple flower
        
        Perigynous
        
        Perianth & stamens adnate to calyx
        
        ex cherry flower
      - Imperfect flowers
        
        Lacking a whorl of sexual organs
        
        Hermaphroditic = perfect
        
        Monoecious = male flowers and female flowers on the same plant
        
        Dioecious = male flowers on plant, female flowers on different plant
        
        Male = androecious
        
        Female = gynoecious
      - Display variation
        
        Inflorescence
        
        Taxonomic importance
        
        Various ways to ensure cross pollination
    - - Major traits
        
        Color
        
        Smell, organic volatiles
        
        Shape
        
        Bloom time
        
        Rewards, eg nectar
        
        Color
        
        Some colors are more attractive than others
        
        Color requires resource
        
        Omit when unnecessary
        
        Some are in the uv spectrum
        
        Scent
        
        Signal to pollinators
        
        Sometimes use own preferences and sexual pheremones
        
        Some common chemicals
        
        Benzaldehyde (almond)
        
        Linalool (lavender)
        
        Limonene (citrus)
        
        Beta ocimene (green)
        
        May have scent glands
        
        eg roses
        
        Shape
        
        Floral symmetry
        
        Actinomorphic
        
        Radially symmetric
        
        eg sunflower
        
        Zygomorphic
        
        Irregular
        
        Bilateral
        
        eg pea
        
        Blooming time
        
        Diurnal
        
        Day time
        
        Nocturnal
        
        Night time
        
        Rewards
        
        3 more items...
    - - Major syndromes
        
        Abiotic:
        
        Anemophily (wind)
        
        Hydrophily (water)
        
        Biotic
        
        Melittophily (bee)
        
        Psychophily (butterfly)
        
        Phalenophily (moth)
        
        Myophily, sapromyophily (fly)
        
        Ornithophily (bird)
        
        Chiropterophily (bat)
        
        Cantharophily (beetle)
        
        Anemophily
        
        Wind
        
        No bright colors, special odors, or nectar
        
        Small
        
        Most have no petals
        
        Stamens and stigmas exposed to air currents
        
        Large amount of pollen
        
        Pollen smooth, light, easily airborne
        
        Stigma feathery to catch pollen from wind
        
        Hydrophily
        
        Water
        
        Copious pollen
        
        Small flowers
        
        Long filaments for pollen transport on surface
        
        Oblong, heavier pollen for submarine transport
        
        Melittophily
        
        Bee
        
        Full of nectar
        
        Brightly colored with petals that are usually blue or yellow or a mixture of these (bees cannot see red) but can in UV
        
        Sweetly aromatic or have a minty fragrance
        
        Open in daytime
        
        Provide landing platforms
        
        Often bilaterally symmetrical (one side of the flower is a mirror image of the other)
        
        Flowers are often tubular with nectar at base of tube
        
        Psychophily
        
        Butterfly
        
        In clusters and provide landing platforms
        
        Brightly colored (red, yellow, orange)
        
        Open during the day
        
        Ample nectar producers, with nectar deeply hidden
        
        Nectar guides present
        
        May be clusters of small flowers (goldenrods, Spirea)
        
        Phaelonophily
        
        Moth
        
        Many night pollinated species
        
        White
        
        Heavy scent
        
        Tubular corollas
        
        Myophily
        
        Fly
        
        Pale and dull to dark brown or purple
        
        Sometimes flecked with translucent patches
        
        Putrid order, like rotting meat , carrion, dung, humus, sap and blood
        
        Nectar guides not present
        
        Produce pollen
        
        Flowers are funnel like or complex traps
        
        Saprophily, for carrion mimics
        
        Ornithophily
        
        Bird
        
        Tubular and have petals that are recurved to be out of the way
        
        Have tubes, funnels, cups
        
        Strong supports for perching
        
        Brightly colored: red, yellow, or orange
        
        Odorless (birds have a poor sense of smell)
        
        Open during the day
        
        Prolific nectar producers with nectar deeply hidden
        
        Modest pollen producers that are designed to dust the bird’s head/back with pollen as the bird forages for nectar
        
        Chiropterophily
        
        Bat
        
        Open at night;
        
        Large in size (1 to 3.5 inches);
        
        Pale or white in color;
        
        Very fragrant, a fermenting or fruit-like odor; and/or
        
        Copious dilute nectar.
        
        Cantharophily
        
        Beetle
        
        Bowl-shaped with sexual organs exposed
        
        White, to dull white or green
        
        Strongly fruity
        
        Open during the day
        
        Moderate nectar producers
        
        May be large solitary flowers (i.e. magnolias, pond lilies)
        
        May be clusters of small flowers (goldenrods, Spirea)
        
        Deception
        
        5 more items...
    - - After double fertilization
        
        Primary endosperm nucleus divides forming endosperm
        
        Zygote develops in embryo
        
        Integuments develop into a seed coat
        
        Ovary wall and related structures develop into fruit
        
        Fruit formation
        
        Ovary sometimes with other portions of flower or inflorescence develops into a fruit
        
        Ovary wall
        
        Pericarp
        
        Thickens and differentiations
        
        Exocarp
        
        Mesocarp
        
        Endocarp
        
        Pericarp
        
        Exocarp
        
        Mesocarp
        
        Endocarp
        
        Accessory fruits
        
        Any fruit with accessory tissue
        
        Tissue besides the ovary is included in the fruit
        
        Can be simple, aggregate or multiple
        
        Parthenocarpic fruits
        
        Fruit development
        
        Without fertilization
        
        Without seed development
        
        Banana
        
        Seedless watermelon
        
        Simple fruits
        
        Single carpel
        
        2+ united carpels
        
        Examples
        
        Bean
        
        Cherry
        
        Tomato
        
        Major fleshy types
        
        Berries
        
        Drupes
        
        Pomes
        
        Major dry types
        
        Dehiscent
        
        Indehiscent
        
        Aggregate fruits
        
        7 more items...
    - - Syndromes
        
        Wind
        
        Water
        
        Animal
        
        Active
        
        Passive
        
        Self
        
        Wind
        
        Wings
        
        Parachutes
        
        Lightweight seeds
        
        Water
        
        Buoyant
        
        Large airspaces
        
        Example coconut
        
        Animal, active
        
        Fleshy
        
        Provide animal with nutrients
        
        Long-distance dispersal
        
        Seed pass through gut without harm
        
        Seeds are regurgitated later
        
        Ends up in a nice little pile of nutrient dense excrement
        
        Ants with elaiosome (lipid based nutrient rich)
        
        Animal, passive
        
        Hooks
        
        Catch on fur
        
        Catch on hoof
        
        Velcro
        
        Self
        
        Gravity
        Exploding
- - - - During Metaphase I
      - Orientation of bivalents is random
      - During Metaphase II
      - Orientation of sister chromatids is random
      - In general, the possibilities are 2n
      - Ex: human with 46 chromosomes
      - 246 = 7.04 x 1013
    - - During Prophase I
      - Synaptonemal complex forms
      - Mixes the genes present in homologous chromosomes
      - Results in new combinations not present in the chromosomes of the parental cells
      - Usually at least one chiasma occurs between every pair of homologous chromosomes
    - - New combination of alleles from each parent
      - Promotes heterozygosity
      - Advantages include
      - genetic diversity
      - Bet-hedging to novel environments
      - Multiple deleterious alleles can be bunched together and eliminated
      - Escape host-parasite negative impacts
      - Pollination
      - Cross pollination vs
      - Self pollination
      - 3 Principles
        
        Dominance
        
        Segregation
        
        Independent Assortment
      - Principle of Dominance
        
        Each individual has a unique genotype
        
        Genotype is made up of alleles
        
        Phenotypes determined by these alleles (and the environment)
        
        There is no guarantee that an allele will manifest
        
        Heterozygosity
        
        One of 2 genes (dominant allele) has a detectable effect on an organism's appearance
        
        The other gene has no discernable effect (recessive allele)
        
        Homozygosity, both alleles are the same
        
        Dihybrid example
        
        Same as previous video
        
        For reference
        
        Parental
        
        True breeding
        
        Homozygous
        
        F1
        
        First filial generation
        
        Heterozygotes
        
        Genotypic ratio
        
        Allele combinations
        
        Phenotypic ratio
        
        Trait combinations
        
        Incomplete dominance
        
        Phenotype of heterozygote is intermediate between those of parent homozygotes
        
        Snapdragons
        
        Red x white = pink
        
        Multiple alleles
        
        Many populations have more than 2 alleles for a particular locus
        
        Punnett square theoretical crossing works similar
        
        Breeding experiments to determine dominance
        
        Figuring out alleles is complex
        
        No crossing over
        
        Fail to mix alleles across homologs
        
        Chromosome inherited same as parent
        
        Only 2 gamete types possible rather than 4
        
        Polygenic inheritance
        
        7 more items...
        
        Mutations
        
        Changes in the genetic makeup of an individual
        
        Point mutation
        
        Single nucleotide change
        
        Chromosome mutation
        
        Deletion
        
        Segments of chromosome are lost
        
        Duplication
        
        Part of the chromosome has doubled
        
        Inversion
        
        Piece rotates 180
        
        Translocation
        
        Exchange of parts between 2 nonhomologous chromosomes
        
        Transposons
        
        Movable genetic element
        
        Jumping genes
      - Principle of Segregation
        
        Alleles are segregated, separated, from one another during meiosis
        
        Each gamete contains only one allele for each gene
        
        Offspring inherit 2 alleles for a gene
        
        One from each parent
        
        Inherit a homologous chromosome
        
        During meiosis, 2 members of a gene pair separate from each other
        
        Each gamete has an equal chance to inherit either one of the genes
      - Monohybrid cross
        
        Punnett square
        
        Visual representation of the offspring inheritance patterns
        
        Monohybrid is a cross between 2 homozygous parents with different alleles.
        
        Principle of Independent Assortment
        
        Gene pairs that are not related (homologs) segregate independently
        
        Gene pairs that are not linked segregate independently
        
        Evidence provided from a dihybrid cross
        
        3:1 phenotypic ratio for each of the 2 alleles
  - - - Allele frequency
      - Number of copies of an allele in a population divided by the total number of alleles for that gene in a population
      - Genotype frequency
      - Number of individuals with a particular genotype in a population divided by the total number of individuals in a population
      - Allele Relative Frequency
        
        Number of copies of an allele in a population
        
        Divided by
        
        The total number of all alleles for that gene in a population
        
        Allele Relative Frequency
        
        Number of copies of an allele in a population
        
        Divided by
        
        The total number of all alleles for that gene in a population
        
        Genotype Relative Frequency
        
        Number of individuals with a particular genotype in a population
        
        Divided by
        
        The total number of all individuals in a population
        
        Hardy-Weinberg equation
        
        predicts an equilibrium-unchanging allele and genotype frequencies from generation to generation-if certain conditions exist in a population
        
        No new mutations
        
        No genetic drift. The population is so large allele frequencies do not change due to random sampling effects
        
        No migration
        
        No natural selection
        
        Random mating
        
        provides a quantitative relationship between the allele and genotype frequencies
        
        HW equations
        
        If, instead, we always use p and q rather than choosing an upper and lowercase letter to represent alleles:
        
        The frequency of the dominant allele is represented by p
        
        The frequency of the recessive allele is represented by q
        
        Thus p+q=1
        
        Therefore (p+q)2=12;
        
        And p2+2pq+q2=1
        
        p2= genotypic frequency of RR
        
        2pq= genotypic frequency of Rr
        
        q2= genotypic frequency of rr
        
        Microevolution
        
        10 more items...
  - - - Overshoot K
      - Result in die off
      - Limited resources
      - Human population size: http://www.worldometers.info/world-population/
      - Population size:
        
        01April2019 10am: 7,694,293,260
      - 31March2020 6:46am: 7,774,589,054
      - 04Nov2020 7:46am: 7,849,224,195
      - 16April2022 2:04pm: 7,940,768,458
      - Growth models
        
        r = intrinsic growth rate
        
        N = population size
        
        K = carrying capacity
        
        dN/dt = population change over time
        
        Exponential growth
        
        dN over dt equals r times N
        
        Logistic growth
        
        dN over dt equals r times N times the quantity one minus N divided by K
      - Model details for population growth
        
        Exponential growth
        
        dN/dt = rN
        
        Logistic growth
        
        dN/dt = rN[(K-N)/K] =
        
        rN(1-N/K)
        
        r- vs K- selected species
        
        r-selected
        
        Grow exponentially
        
        Disturbed areas
        
        Weedy
        
        Annuals
        
        Little investment in defense
        
        Many, small fruits
        
        K-selected
        
        Fluctuate around carrying capacity
        
        Fairly stable habitats
        
        Perennials
        
        Invest in defenses
        
        Resource-intensive fruits
        
        Plant strategies
        
        Plants must make trade-offs due to environmental necessities
        
        Many strategies exist
        
        Grime’s model
        
        Stress
        
        Resource availability
        
        Water
        
        Nutrients
        
        Light
        
        Growth inhibitors
        
        Temperature
        
        Toxins
        
        Disturbance
        
        Biotic
        
        Herbivory
        
        Pathogens
        
        Anthropogenic
        
        Abiotic
        
        Fire
        
        Wind
        
        3 life stages
        
        C- competitors
        
        S- stress tolerators
        
        R- ruderals
        
        Life history
        
        To predict if a population will grow or shrink, ecologists need to know birth and death rates for organisms at different ages as well as the current age and sex makeup of the population.
        
        Life tables summarize birth and death rates for organisms at different stages of their lives.
        
        Population age structure—Are there lots of: young individuals? Old individuals? Reproductive age individuals?; and similar questions
        
        Population growth rate—How fast is the population size growing (or shrinking)? Population survivorship patterns—Does most mortality occur in the very young? The very old? Or equally across all ages?
        
        Life table practice, R0
        
        Calculate the net reproductive rate (R0)
        
        Calculated by taking the sum of the offspring/individual column.
        
        Represents the expected number of offspring an individual will produce over its lifetime in the population.
        
        If R0>1, the population size increases.
        
        If R0<1, the population size decreases, and
        
        if R0=1, then population size does not change.
        
        Life table practice, G
        
        Calculate the mean generation time (G)
        
        Calculated by taking the sum of the Age-weighted fecundity column and then dividing by the net reproductive rate
        
        Represents average time between two consecutive generations in the lineage of a cohort
        
        The average age between parent and offspring
        
        For humans, typically 20-35 years of age
        
        Life table practice, r
        
        3 more items...
        
        Age distribution
        
        x = age
        
        Nx= number of individuals alive at age x
        
        Sx= proportion of individuals of age x that survive to age x+1;
        
        Nx+1/Nx
        
        lx= proportion of individuals that survive from birth (age 0) to age x;
        
        Nx/N0
        
        Fx= average number of offspring born to a female while she is age x
        
        lx(Fx) = average number of offspring per capita at age x
        
        lx(Fx)x = average number of offspring per capita at time x, weighted by age x
- - - - Only at tips find organisms that require oxygen in high concentrations
      - Early thermophiles gave way to cooler environments
      - Photosynthesis limited by temperature and unknown above 74C
      - ~3.5 bya Stromatolites
        
        Important to understanding the origin of photosynthesis
        
        Layers of photosynthetic bacteria/cyanobacteria
        
        Secrete mucilage sticking together in thin mats on rock surface
        
        Create bands of sediment and dead bacteria, growing similar to reef
      - Cyanobacteria
        
        Cyanobacteria likely the oldest known fossilized organism
        
        Close to LUCA ~3.5-3.8bya
        
        Fossils very similar to present day species cell structure
        
        Chemical clues, 2-methylhopane almost exclusive in cyanobacteria cell walls
        
        ~2bya Rusting of the earth :
        
        Took time to build up enough photosynthesizers
        
        Iron is plentiful on Earth
        
        Early on very little free oxygen (prior to 3bya)
        
        Iron depleted and then oxygen began to build up in atmosphere
        
        Changing environment
        
        Iron formations disappeared
        
        Iron-rich oceans were gone
        
        Iron loving microbes dropped out of fossil record
        
        Oxygen enriched oceans precipitated iron
        
        Photosynthesis reverses respiration
        
        2 stages:
        
        Thylakoid reaction
        
        Light reactions
        
        Stromal reactions
        
        Dark reactions
        
        Calvin-Benson- Bassham Cycle
        
        Likely evolved in small bits
        
        Thylakoid reactions involve dozens of pigments, specialized electron-handling complexes and all lined up precisely in membranes
        
        Photosynthetic pigments
        
        Likely started as sunscreen
        
        Early atmosphere without oxygen, so without the protective ozone layer
        
        Cyanobacteria with scytonemin in sheath, pigment that protects them for UV radiation
        
        Chlorophyll similar to hemoglobin and likely common ancestor
        
        Pigments
        
        Molecules that absorb particular wavelengths of light energy and reflect others
        
        Plants appear to be which color?
        
        This is due to ___ of green light?
        
        Refection
        
        Absorption
        
        transmission
        
        Absorbed light energy
        
        Causes electrons to become excited
        
        Electron bumps to the next orbital
        
        Fate of electron
        
        Passed to electron acceptor
        
        Fall back down to original orbital
        
        Releasing energy
        
        Heat
        
        fluorescence
        
        Absorbance spectrum
        
        Amount of energy absorbed depends on the pigment
        
        Electromagnetic spectrum holds much energy that cannot be used
        
        Visible spectrum used
        
        Chlorophyll
        
        Chlorophyll a
        
        Most abundant pigment in plants
        
        Peak absorbance
        
        430 nm
        
        660 nm
        
        Chlorophyll b
        
        Second most abundant pigment
        
        Peak absorbance
        
        450 nm
        
        650 nm
        
        Action spectrum
        
        Indicates that Chl a & b not only pigments
        
        Must have accessory pigments
        
        Accessory pigments
        
        Carotenoids
        
        Beta carotene
        
        Help broaden absorption spectrum
        
        Also act as sunscreen
        
        Visible during the fall
        
        Resonance energy
        
        Energy absorption and excitation occurs in organized complexes of pigments & proteins called photosystems
        
        Absorbed energy is moved around via resonance energy
        
        Funnelled to reaction center
        
        Special Chlorophyll a
        
        Controlled energy release
        
        Energy of excited electrons released in a stepwise controlled manner
        
        May have evolved initially as a way to dissipate excess energy
        
        Some of the energy used to make stable, energy-rich molecules that can be used by living cells
        
        Photosystems
        
        Consist of
        
        Antennal complex
        
        Accessory pigments
        
        Chlorophyll pigments
        
        Reaction center
        
        Embedded in thylakoid membrane
        
        Photosystems connected by ETS
        
        Electron passed from PSII to PSI
        
        Excited PSII electron grabbed by pheophytin
        
        Passed to plastoquinone
        
        Passed to cytochromeb6f complex
        
        Passed to plastocyanin
        
        Passed to PSI
        
        Electron from PSI to NADP+
        
        Cyclic photophosphorylation
        
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    - - Present atmospheric level oxygen
      - ~20.9%
      - ~535x more O2 than CO2
      - during appearance of land plants
      - 8-15x higher in CO2
      - ~4% O2
      - Kept tissues thin as internal environment quickly anoxic
      - Very weak ozone
      - Terrestrialization
        
        ~470Ma
        
        Major evolutionary changes in morphology & reproduction
        
        Multicellular sporophyte
        
        Retain the zygote & embryo within the female gametophyte
        
        Apical cells with 3 cutting faces allow for 3-dimensional parenchymatous tissue
        
        Evolved from Algae
        
        Charophycean green algae
        
        Streptophyta
        
        Group includes Embryophyta and charophytes
        
        Sometimes grow as flat disc very similar to present day liverworts
        
        Fossil evidence
        
        Earliest evidence from spores and tissue fragments
        
        Mid-Ordovician 470 Ma
        
        Sporopollenin wall
        
        Trilete mark
        
        Cryptospores
        
        Likely liverwort
        
        Liverwort macrofossils
        
        ~390 Ma
        
        Middle Devonian
        
        Dichotomously branched
        
        First macrofossils
        
        Cooksonia sporophytes
        
        Mid-Late Silurian
        
        ~425 Ma
        
        Gametophytes complex
        
        Stomata
        
        Conducting elements
        
        Similar to extant liverworts
        
        Vascular plants
        
        Specialized conducting cells
        
        Evidence from spores ~443 Ma
        
        Tracheid fossils ~415 Ma
        
        Diversity exploded in Devonian (415-360Ma)
        
        Dominant sporophyte no longer restricted to damper areas
        
        Sporophyte generation
        
        Alternation of generations
        
        Gametophyte dominant in early land plants
        
        Sporophyte evolves dominance
        
        Vascular tissue
        
        2 more items...
        
        Leaves & Stomata
        
        4 more items...
    - - haplontic (Greek, haploos + einai = single being)
      - Alternation of generation
        
        Current land plants
        
        haplodiplontic (Greek, haploos + diploos + einai = single double being)
        
        Antithetic theory
        
        Aka interpolation theory
        
        Predictions
        
        Heteromorphic generations
        
        Sporophyte
        
        Short-lived
        
        Simple
        
        Gametophyte
        
        Relatively complex
        
        Persistent
        
        Marchantiophyta
        
        Marchantia liverwort example
        
        Dominant leafy gametophyte
        
        Temporary diploid sporophyte
        
        Gametophyte
        
        Dominant life stage
        
        Antheridiophore
        
        Male
        
        Antheridia
        
        Contain sperm
        
        Archegoniophore
        
        Female
        
        Archegonia
        
        Contain eggs
        
        Sporophyte
        
        Small, temporary structure
        
        Parasitic on gametophyte
        
        Meiosis occurs within sporangium
        
        Sporocytes (2n)
        
        Spores (1n)
        
        Bryophyta
        
        Mnium moss example
        
        Dominant leafy gametophyte
        
        Temporary diploid sporophyte
        
        Gametophyte
        
        Dominant life stage
        
        Antheridial head
        
        Male
        
        Antheridia
        
        Contain sperm
        
        Archegonial head
        
        Female
        
        Archegonia
        
        Contain eggs
        
        Lycophyte
        
        Selaginella example
        
        Heterosporous
        
        Retained within spore walls
        
        Sperm must still swim to egg
        
        Monilophyta
        
        Polypod fern example
        
        Independent gametophyte
        
        Independent sporophyte
        
        Gymnosperm
        
        Pine example
        
        Microgametophyte no longer restricted to water
        
        Megagametophyte protected by integuments
        
        Angiosperm
        
        Lily example
        
        Sporophyte dominant
        
        Gametophytes microscopic
        
        Microgametophyte
        
        Multicellular haploid stage
        
        Pollen grain
        
        Immature
        
        Mature germinating
        
        Megagametophyte
        
        Multicellular haploid individual
        
        Egg one of the cells (nuclei)
    - - One of the earliest features of land plants
      - All but liverworts with examples
      - Stomata
        
        Small pore bounded by specialized epidermal cells, guard cells
        
        Permit rapid gas exchange in higher plants
        
        Oxygen out
        
        Carbon dioxide in
        
        Control of water loss permit giants among plants
      - Similar shapes
        
        Early Devonian sporangia ~400 mya stomata scattered across sporangia
        
        Extinct lineages
        
        Rhyniophytes, Cooksonia
        
        Similarities link to similar functions in extant angiosperms
        
        Some evidence of air chambers
        
        Bean-like shape
        
        Inner wall thickening
        
        Aid in desiccating sporophyte
        
        Likely the origin of stomata
        
        Aid in desiccation of sporophyte
        
        Stomata near sporophyte sporangia
        
        Aid in spore dispersal
        
        Likely not regulated
        
        May have permitted some CO2 to enter
        
        No intercellular space
      - Lower stomatal frequency
        
        Support early role different from today
        
        Location on non-photosynthetic sporophyte tissue in early lineages
        
        Extant early lineages have stomata that only open
        
        Intercellular spaces
        
        Pseudostomata continuous with epidermis or hypodermis, no space
        
        Space filled with fluid with space made by cells pulling apart
        
        Stomatal canal, small air space
        
        Aid in diffusion of minerals and nutrients from gametophyte to sporophyte
        
        Cell death
      - Flowering plants
        
        Monocot (grasses)
        
        Dumbbell shape
        
        Same direction as epidermal cells
        
        Eudicot
        
        Kidney-shaped
        
        Random orientation
        
        Guard cell control
        
        Active metabolic processes
        
        Increase turgor pressure
        
        Moves ions, water follows by osmosis
        
        Hypotonic to hypertonic
        
        Cytoskeleton microfibrils radially oriented
        
        Photosynthetic dependent
        
        Provides ATP for potassium pump
        
        Protons are pumped out
        
        Potassium are moved in
        
        Ancestral condition filled with chloroplasts
        
        Independent of blue light
        
        Closure at night or under water stress
        
        Water use efficiency
        
        Amount of water loss to carbon gain
        
        Close pore during water stress
        
        Reduce transpiration
        
        Maintain hydration
        
        Derived character
        
        Reduce probability of cavitation
        
        ABA responsive in seed plants
        
        Angiosperms additionally respond to VPD
    - - Apomorphy
      - derived novel trait
      - Synapomorphy
      - apomorphy shared by two or more taxa
      - hypothesized to have evolved in their most recent common ancestor
      - synonymous with homology
      - Autapomorphy
      - character newer than
      - Plesiomorphy
      - character older than
      - Homoplasy
      - convergent evolution leads to species independently sharing a trait that is different from the trait inferred to have been present in their common ancestor
      - Convergence
      - independent evolution of a similar trait in two or more taxa.
      - trait has gained or lost independently in separate
      - Apical meristem
        
        Totipotent region
        
        Ancestral, found in charophytes
        
        Growth by mitosis
      - Mitosis review
        
        Mitosis
        
        Prophase
        
        Metaphase
        
        Anaphase
        
        Telophase
        
        Cytokinesis
        
        Apical meristem synapomorphy
        
        Charophytes mainly filamentous
        
        Bryophytes protonema
        
        Filamentous
        
        Apical bud
        
        2D to 3D switch
        
        Linear growth such as filamentous algae
        
        Only divide at tip
        
        Cytokinesis in a single plane
        
        Leafy shoot growth in three dimensions
        
        Cytokinesis in oblique planes
        
        Bifurcating sporophyte
        
        Splitting shoot tip into 2
        
        Laid foundation for multiple sporangia (polysporangiate)
        
        Large complex plants
        
        Specialized organ systems
        
        Bryophytes are not
        
        Unique mutant
        
        Simple early fossils
        
        Cooksonia eg
        
        Current day Lycophytes
        
        Terminal sporophyte replaced
        
        Displace sporangium
        
        Side axial
        
        On leaf
        
        Some tips sterile
        
        Necessary prior to indeterminancy
        
        Polysporantiate
        
        Bifurcate branching
        
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        Indeterminacy
        
        Vascular plant synapomorphy
        
        Grow continuously
        
        Produce new organs
        
        Produce new tissue
        
        From shoot apex
        
        Displace terminal sporangia onto lateral branches
        
        Likely evolved after vasculature based on fossil evidence
        
        Convergent evolution
        
        9 more items...