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Exam 3 Botany - Coggle Diagram

- - - - Water transport system energetically efficient (don’t starve)
        
        Minimal maintenance = cell death
        
        Transport energy minimal
        
        Water filtration close to soil access
  - - - taller plants
      - More developed tree canopies
    - - More xylem, wider xylem & longer conduits
    - - monocotyledonae
      - arborescent
        
        no secondary growth
  - - - Carboniferous
      - ~320mya
      - Vascular cambium only divided internally
    - - Devonian/Carboniferous
      - Reproduced via spores
    - - Lycophytes
      - Euphyllophyte
  - - - xylem (wood)
      - phloem (inner bark)
      - Ground tissue (rays)
  - - - Stem cells
      - Xylem and phloem
      - Fascicular cambium
    - - Stem cells
      - Ray cells
      - Interfascicular cambium
    - - More xylem & phloem
    - - Wider circle of vascular cambium
  - - - Unique for each face
      - Longitudinal
      - Transverse
      - Radial
    - - Fusiform - longitudinal
      - Ray - radial
  - - - Early wood
      - Late wood
  - - - Functions in water transport
    - - Functions in storage
      - Can no longer transport water
  - - - Tracheids only
      - Little room for fibers
      - Gymnosperms
    - - Vessel elements’ efficiency permit space for fibers
      - Angiosperms
  - - - Rays connect
        
        Pith
        
        Cortex
    - - Xylem
        
        Wood
        
        Primary & secondary
    - - Inner bark
        
        phloem
        
        cortex
      - Secondary
      - Primary squished
      - Lots of fibers
    - - Outer bark
      - Phellem
        
        cork
      - Phellogen
        
        cork cambium
      - Phelloderm
- - - - Water moves from less negative water potentials to areas of more negative water potentials
  - - - 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.
        
        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
      - ψπ = osmotic potential:
        
        effect that solutes have on ψ
        
        Adding solutes decreases water’s free energy, so ψπ is always negative.
        
        Difference between the solution and pure solvent resulted after adding solutes
      - 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.
        
        Adhesion of water molecules to nondissolved structures
        
        Example, soil particles
        
        Always negative
        
        Significant only outside living systems in very dry soils
  - - - Stomata open shortly after daybreak
      - Close at times of stress
      - Close at night
    - - Open stomata
      - Water evaporates from intercellular spaces
      - Starts the domino effect of water potentials
    - - Water moves from hypotonic to hypertonic solutions
        
        Root hairs greatly increase surface area
    - - Casparian strip of root endodermis
      - Forces symplastic movement
      - Embolism is an air pocket
        
        Completely makes tracheary element non functional
    - - 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.
    - - 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
    - - Sugars transported as sucrose
      - Actively transported into sieve elements
      - Decreases water potential of STE
    - - Creates a water potential gradient between sieve tube elements and surrounding cells
    - - 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
    - - Sucrose actively transported from sieve tube
        
        By companion cells
        
        Stored as starch
        
        Used in metabolism
        
        Aerobic respiration
- - - - no specialized cells
        
        Poikilohydric
        
        Water-storage extend
        
        Equilibrate water potential through environmental source
        
        water content changes with the moisture in the surrounding environment
        
        Stayed small to reduce demand for water
        
        Live in perennially wet substrates (stream sides)
        
        More derived homoiohyd
    - - hydroids
        
        Bryophytes
        
        imperforate
        
        No plasmodesmata
        
        Aid in refilling from cavitation
        
        Water conducting cell
        
        Apomorphic trait to true vascular tissue
        
        similar function but different origin
        
        No lignin
    - - 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
      - improve water flow
      - Tracheids
        
        Early Tracheids
        
        lignified
        
        Relatively long and wide
        
        Ferns
        
        Tracheids + vessel elements
        
        in rhizomes of some species
        
        Lycophytes
        
        Pit membranes
        
        Water transport only (no support)
        
        True Tracheids
        
        Lignified with ornamented walls
        
        Banded or pitted
        
        Evolved likely once
        
        Tracheophytes
        
        Function in both
        
        Water transport
        
        Support
        
        Tapered at ends
        
        rather narrow
        
        Thought to have evolved into
        
        Vessel Elements
        
        Angiosperms
        
        Homogenous pit membrane
        
        Large diameter
        
        Dead and maturity
        
        Open, digested end walls
        
        Cross View
        
        Longitudinal View
        
        Differentiation
        
        Steps
        
        next
        
        1 more item...
        
        Elongation
        
        1 more item...
        
        Dead at maturity
        
        start with
        
        1 more item...
        
        Highly Evolved Tracheids
        
        Pine Tracheid Example
        
        Function in water movement & support
        
        Torus-margo pit membrane
        
        Move to prevent cavitation
        
        Both angiosperm and gymnosperm
      - 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
      - Gymnosperm vs Angiosperm
        
        Angiosperm
        
        Vessels can have greater
        
        Maximum lengths
        
        maximum diameters
        
        Vessel elements may be short but the vessel can be much longer
        
        use of vessel elements results
        
        Lowers the cost (construction & transpiration)
        
        Having vessels permits more fiber (hardwood vs softwood)
        
        because not all cells must be devoted to vessel elements
        
        Downside is greater cavitation risk
        
        filling vessel element with air
        
        yields greater conductivity in vessel elements
        
        both tracheids and vessel elements
        
        Flowering Plants
        
        Gymnosperms
        
        only tracheids
        
        Pines and Cedars
  - - - Tracheids
        
        Annular thickenings
        
        Cooksonia
        
        Thought to be true tracheids
      - Some earliest plants to show vascularization
        
        lycophytes
        
        early vascular group
        
        created towering forests during Carboniferous
  - - - Synapomorphy
      - All have vascular tissue
      - Cell type varies
      - Vascular architecture diverse
  - - - in order to function correctly
        
        requires water from xylem
    - - food conducting cells
        
        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
    - - Together: Transport of
        
        Photosynthate
        
        Hormones
        
        Electric signals
      - always with albuminous cells
        
        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
    - - 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
      - and companion cell
        
        features
        
        Transport of
        
        Photosynthate
        
        Hormones
        
        Electric signals
        
        Sieve tube element
        
        Sieve plate
        
        Sieve pore
        
        Lateral sieve area
        
        P protein
        
        may help in plug pores in response to leakage
        
        Plastid
        
        sieve element plastids
        
        Smooth ER
        
        lost ribosomes
        
        highly folded
        
        Mitochondria
        
        very few
        
        forisomes
        
        legumes
        
        plug pores
        
        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
    - - Cell wall thickened
      - Cytoplasmic clearing
        
        No ribosomes
      - Callose deposited around terminal plasmodesmata
      - Nuclear break down
      - Formation of sieve plate & pores
  - - - 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
    - - Complexity increased
      - Stem diameter increased
      - Plant height increased
      - Led to compartmentalization
      - Selected for a woody habit
    - - 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
    - - 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 siphonosteles
    - - exarch
      - protostele
        
        most ancestral type of stem vasculature
    - - Siphonostele
        
        Xylem surrounded by phloem
      - Endarch
    - - Atactostele
        
        Numerous vascular bundles scattered throughout stem
      - No pith
      - Vascular bundles often surrounded by sclerenchyma
        
        Bundle sheath
    - - Eustele
        
        Phloem outside xylem
        
        Bundles separated by parenchyma
      - Endarch
        
        Metaxylem outside protoxylem
      - Vascular bundle supported by sclerenchyma, bundle cap
- - - - High atmospheric global temperatures
      - Low stomatal densities
        
        Increase permit greater evaporative cooling
      - Low capacities for water uptake prior to root evolution
      - Lacking efficient vascular transport in leaves
        
        Burn up leaf
        
        Vascular embolism
    - - 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
    - - Leaves had at least 5 independent origins
        
        Liverwort gametophyte
        
        Moss gametophyte
        
        Lycophyte sporophyte
        
        Monilophyte sporophyte
        
        Spermatophyte sporophyte
    - - 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
    - - 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
    - - 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
    - - Ground tissue
      - Specialized parenchyma
      - Contains air spaces from cells being digested
      - Main function permit gas-exchange
      - Large air pockets for buoyancy in aquatic plants
    - - Ground tissue
      - Thickened primary cell walls
      - Main function in flexible support
      - Found in bundle sheath of veins in some species
    - - Xylem
        
        Tracheids
        
        Water transport
      - Phloem
        
        Sieve tube element/ sieve cells
        
        Companion cells/ albuminous cells
        
        Photosynthate transport
      - In veins
    - - 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
    - - 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
    - - 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
- - - - Uni-multicellular projections
      - Anchorage
      - Some with mineral uptake
      - Genes
        
        predate land plants
        
        play a role in root hair development
    - - 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
    - - Diversity of arrangement used to infer phylogeny
        
        Number of initial cells differs
      - Similar genes across plant taxa
      - Similar genes in shoot to root
  - - - 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
    - - 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
      - Apical meristem
        
        Quiescent center
        
        Rarely divides
        
        Backup plan
        
        Maintains initial cells
        
        Behind root cap
      - Root Cap
        
        Evolved independently
        
        Lycophyte
        
        Euphyllophyte
        
        Protect underlying tissues
        
        Cells that slough off
        
        Secrete mucilage
      - 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
  - - - Selaginella sp example
      - No root cap
      - No root hairs
    - - Diversity
      - Pith in center
      - Endodermis
        
        Surrounded by cortex
      - Details
        
        Epidermis
        
        Cortex
        
        Endodermis
        
        Casparian strip
        
        Pericycle
        
        Xylem
        
        Phloem
        
        Pith
    - - Diversity
      - No pith
      - Endodermis
      - Cortex
      - Details
        
        Epidermis
        
        Cortex
        
        Endodermis
        
        Casparian strip
        
        Pericycle
        
        Xylem
        
        Phloem
- - - - derived novel trait
    - - apomorphy shared by two or more taxa
      - hypothesized to have evolved in their most recent common ancestor
      - synonymous with homology
    - - character newer than
    - - character older than
    - - trait has gained or lost independently in separate lineages during evolution
      - convergent evolution leads to species independently sharing a trait that is different from the trait inferred to have been present in their common ancestor
    - - independent evolution of a similar trait in two or more taxa.
  - - - Totipotent region
        
        continuously divide mitotically
      - Ancestral
        
        found in charophytes
        
        mainly filamentous
        
        Bryophytes protonema
        
        filamentous
        
        apical bud
      - Growth by mitosis
        
        mitosis review
        
        Mitosis
        
        Prophase
        
        Metaphase
        
        Anaphase
        
        Telophase
        
        Cytokinesis
      - Shoot Apical Meristem
        
        totipotent region
        
        continuiously divides
        
        matures in to transitions tissues
        
        procambium
        
        ground tissue
        
        protoderm
    - - 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
        
        Evolved prior to vascularization
        
        Lycophytes various branching structures
        
        Equal branching
        
        Isotomous
        
        Unequal branching
        
        anisotomous
      - Leads to 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
        
        Indeterminate meristems
        
        may evolved independently
        
        in following
        
        fern (monilophyte) gametophyte
        
        vascular plant sporophyte
        
        bryophyte gametophyte
        
        Vascular plant meristems
        
        may evolved independently
        
        lycophytes (multicellular)
        
        monilophytes (single cell)
        
        spermatophytes (multicellular)
        
        selective pressure for evolution of indeterminacy