Course Mind Map
Respiration
Fermentation of Alcoholic Beverages
Yeasts ferment glucose
Anaerobic process
examples
Spirits
Beer 
Wine 
ethanol content above 20%
Liquor 
Environmental Factors
Temperature
Lack of Oxygen
Increase or decrease
Leads to increase or decrease in respiration
Cell's access to oxygen varies
More variable for roots
Only produced during daylight
Internal Factors
Internal Regulation
Respiration is subject to specific metabolic controls
Total Energy Yield
Lipid Respiration
Variable
Pentose Phosphate Pathway
2 to 6 NADPH -> 0 to 12 ATP
Anaerobic
2 ATP
Aerobic
2 ATP
2 NADH -> 4/6 ATP
1 NADH -> 6 ATP
3 NADH -> 18 ATP
1 FADH2 -> 4 ATP
Heat-Generating
None
Photorespiration
None
Respiratory Quotient
Acids: RQ = >1.0
CO2 liberated : O2 consumed
For glucose:
RQ = 1.0
Fatty Acids:
RQ = 0.7
Types
Lipids
Catabolic metabolism
Broken down into glycerol, triglycerides, and phospholipids
Beta Oxidation
Further broken down into acetyl CoA
Heat Generating
Maintains body temp in mammals
Energy lost during each step
mitochondrial electron transport
Glycolysis
Citric acid cycle
Generate more heat through shivering when cold
Anaerobic
Respiration without oxygen
Often called fermentation
obligate anaerobes
Bacteria that are exclusively
anaerobic
Killed by oxygen
Aerobic
Oxygen is terminal
electron acceptor
Animals & Plants
are aerobic
Obligates or Strict Aerobes
Facultatively aerobic
fungi and certain types
of tissues in animals
and some plants
Oxygen present=aerobic
Not present=anaerobic
Can carry out both types
Pentose Phosphate Pathway
Parallel to glycolysis
Essential for many metabolic pathways
Transforms glucose into erythrose and ribose
Less important as a source of respiratory energy
More significant for its role as a synthetic pathway
Photorespiration
Only when RuBP carboxylase adds oxygen instead of CO2
Photosynthesis #
Energy Carriers
ATP 
Converted to ADP and phosphate
Guanosine Triphosphate
Phosphorylated to ATP
2 ways
Photophosphorylation
(Substrate-level)
Oxidative Phosphorylation
Other e- carriers
Cytochromes
small proteins containing a cofactor, heme.
only carry e- short distances
Plastoquinones
transport e- short distances
Hydrophobic
dissolve easily in lipids
Hydrocarbon tail
Plastocyanin
small protein
carries e- on a metal atom
copper
loosely associated with chloroplast membranes
can move a short distance along surface, but not far
Reducing Power
Oxidized
atom does not carry as many e- as it could
Examples
Carbon : CO2
Sulfur : SO2-
Nitrogen : NO3-
Compounds often contain lg amt of O
Pulls away e-
Reduced
e- are added to an atoom
Compounds contain H
Ability to force e- onto cmpds
Other
Related Rxns
Reduction Rxn
reduces + chrg on atom
Oxidation Rxn
increases + chrg on atom
Environmental & Internal
Factors
Light 
3 important factors
quality
quantity
duration
Leaf Structure
palisade parenchyma above & spongy mesophyll below
excellent for absorbing CO2
Inefficient for conserving water
Water
Stomata kept open during day
loss of water
Stomata closed at night
retains water
C4 Metabolism
- CO2 is absorbed
- Transported through
- Concentrated in leaf
Oxygen is kept away from carboxylase
Occurs in leaves with Kranz anatomy
Crassulacean Acid Metabolism
(CAM)
Improves conservation of water
Still permits photosynthesis
Light-Dependent Rxns
Thylakoid rxn
Requires light energy and water
Creates intermediates to act on CO2
ATP
NADPH
Anabolic Metabolism
Builds up larger,
more complex molecules
2 important pathways
Synthetic Pathways of polysaccharides and fats
storage forms of energy and carbon
gluconeogenesis
anabolic synthesis of glucose
Stroma Reactions
formerly dark rxn
Light-Independent
ATP and NADPH react w/ CO2
produces carbohydrate
Calvin/Benson Cycle 
C3 rxn
Tissues & Primary Growth of Stems
Stem Growth & Differentiation
Apical Meristems
Cells divide by
mitosis
cystokinesis
Subapical Meristems
Right below apical meristem
cells also grow & divide
Produce cells for region below
Protoxylem
First xylem to appear
Metaxylem
has longest time for growth
Vascular Bundle
Exterior cells
protophloem
Cells closest to metaxylem
metaphloem
Protoderm
epidermal cells
early stages of differentiation
Provascular tissues
Young cells of xylem & phloem
Ground meristem
Young cells of pith and cortex
External Organization 
Stem
An Axis
Shoot
Stem
Leaves
Flowers
Flowers
Nodes
Where leaves attatch
Internodes
Space bt Nodes
Leaf Axil
Stem area above where leaf attaches
Axillary Bud
Within Leaf Axil
Miniature shoot
Dormant apical meristem
Several young leaves
Vegetative
Grows into branch
Floral
Grows into flower
Bud Scales
Modified Leaves
Smalll
Corky
Waxy
Terminal Bud
At extreme tip of stem
Internal Organization 
EPIDERMIS
Outermost layer
Single layer of living Parenchyma cells
Differs from human epidermis
Thicker
Many layers of dead cells
Cutin
Encrusts outer tangential walls
Fatty substance
Makes wall impermeable to water
Cuticle
More/Less pure layer of cutin
Stoma
Guard cells
Stomatal Pore
CORTEX
Interior to epidermis
SImple
Homogenous
Composed of
Photosynthetic parenchyma
Sometimes collenchyma
VASCULAR TISSUES
Xylem
2 types of conducting cells
Tracheids
Vessel elements
Phloem
2 types of conducting cells
Sieve cells
Sieve tube members
VASCULAR BUNDLES
Xylem & Phloem together
Types of
Cells & Tissues 
Parenchyma
Most common
Cells
Only primary walls
Remain thin
Tissues
Mass of parenchyma cells
Constitutes soft part of plants
Soft Leaves
Petals
Fruits
Seeds
Collenchyma
Primary cell wall
Thin in some areas
Thickened in other areas
Corners
Important to its:
Function
Existence
Only in shoot tips and petioles
Stretchy
Must be short to be strong
Parenchyma needed for support
Sclerenchyma
Used for strength
Cell walls
Thin Primary
Thick secondary
Almost always lignified
Elastic
Developed from Parenchyma
Structure of woody plants
Sapwood
Lighter
Moister
Outer region
Heartwood
Dark wood
Dry
Inner portion (center)
More fragrant
Vascular Cambium
Initiation
continues to divide
Constitutes fascicular cambium
Fusiform Initials
Long, tapered cells
140 to 462 micrometers in dicots
700 to 8,700 micrometers in conifers
Undergo periclinal division
produces 2 elongate cells
1 becomes cell of secondary xylem or phloem
Ray Initials
Short and cuboidal
Periclinal division
1 becomes xylem or parenchyma if inner cell
or becomes phloem parenchyma if outer cell
Arrangement of Cambial Cells
Ray: grouped together in short vertical rows
1 cell wide
2 cell wide
many cells wide
Fusiform
Regular, horizontal rows
Irregular, no horizontal pattern
Produces secondary
plant body
Types of Wood Cells
Secondary Xylem
Wood
Developed from cells formed interior to vascular cambium
Contains all types of cells of primary xylem
No new cells
May contain
Tracheids
vessel elements
fibers
sclereids
parenchyma
Secondary Phloem
Formed from vascular cambium also
Contains
Sieve tube members
Companion Cells
In angiosperms
Sieve cells
In conifers
Difference bt Primary & secondary xylem
origin of cells
arrangement of cells
Hardwood
Most commercially important angiosperm wood
Contains fibers making them
strong
tough
useful for construction
Term used for woods of
All angiosperms
All eudicots
Even balsa
Lack fibers
Very soft
Softwood
Have few/no fibers
Softer consistency
Some instances are harder than hardwood
Inner Bark
All secondary phloem between
vascular cambium
innermost cork cambium
Outer Bark
Cork Cambium
Phellogen
Cuboidal Cells
Inner cell remains cork cambium
outer cell differentiates
Cork cell (phellem)
Phelloderm
layer of parenchyma
Periderm
Cork Cells
Cork Cambium
Phelloderm
Lenticels & Oxygen Diffusion
Initiation of Cork Cambia
All tissues outside the innermost cork cambium
Growth Rings 
Early Wood
Spring wood
First wood formed
Must have high proportion of wide vessels
Wide tracheids in conifers
Late Wood
Summer wood
Thickened Cuticle
Less transpiration
Large #'s of newly formed vessels
Lower proportion of vessels
Needs more mechanical strength
Annual Ring
Early wood
Late wood
One year's growth containing
Anomalous Forms of Growth
Secondary Growth
Secondary bodies
produced by alternative cambia
Differ from common type
Unsual Primary Growth
Example:
Palm tree
trunks don't taper at tips
Reaction Wood
Forms in place of normal wood
Forms in response to stress
In angiosperms
Upper side of branch
tension wood
Transport process
Pressure Potential
Psi w/ subscript p
the effect pressure has on water potential
Osmotic Potential
Psi w/ subscript pi
the effect solutes have on water potential
Matric potential
Psi w/ subscript m
water's adhesion to nondisolved structures
Cell walls
Water Potential
Free energy of water
Botany's chemical potential
How to Increase
Heat water
Put the water under pressure
Elevate the water
How to decrease
Cool the water
Reduce the pressure
Lower it
Material moves through a solution and across a membrane
Diffusion
High to low concentration
Osmosis
Diffusion of water through a membrane
Active Transport
The use of ATP to pass through membrane
Types of membranes
Freely
Permeable
Have little biological significance
all solutes can diffuse through
Completely impermeable
Nothing can pass through
Act as isolation barriers
Selectively Permeable
only allow certain substance to pass through
All lipid/protein membranes
Short-Distance Intercellular Transport
Symplast
One continuous mass of protoplasm in one plant
Apoplast
Cell wall and intercellular spaces
Long Distance Transport
Phloem
Pressure Flow Hypothesis
Theory to explain movement of sap through phloem
Sources
sites from which water & nutrients are transported
Sugars are actively transported
Polymer trap mechanism
Conducting-cell plasma membranes
Permeable to monosaccharides & disaccharides
Impermeable to polysaccharides
Sinks
Sites that receive transported phloem sap
Xylem
Properties of water
Cohesive
Water is attracted to water
Adhesive
Water is attracted to other substances
Water Transport through Xylem
cohesion-tension hypothesis
Explains the ascent of water from roots to leaves
Most widely accepted model of the process
Transstomatal transpiration
Loss of water through the stoma
More significant than transcuticular
Transcuticular Transpiration
Loss of water through cuticle
Control of water transport by Guard Cells
Water movement is primary means of carrying minerals upwards
Water moves from roots to shoots
Evaporative cooling
Prevents heat stress in leaves and young stems
Short distance Transport
Guard Cells
Curved cells around a stoma
Motor Cells
Located at "joints" in lamina or stem
Accumulate/expel K
Adjusting their water potential
Transfer Cells
Specialized parenchyma cells
Have increased surface area
Genetics
Multiple Genes for
One character
Epistasis
Having multiple genes for each trait
Quantitative Trait Locus Analysis
numerous crosses to determine how much various genes contribute to a particular phenotype
Pleiotropic effects
Multiple phenotype effects of one mutation
Replication of DNA
Happens during S phase
Doubles amount of DNA
Each gene exists in at least 2 copies
1 on each of 2 chromatids
Replicon
small "bubble"
Formed from two strands separating
Primer RNA
starting point for synthesis
approx. 10 nucleotides long
DNA polymerase
DNA-synthesizing enzyme
Ligate
attachment of new DNA together
Covalent bonds
Replication fork
forked appearance
formed when DNA uncoils & separates
Other aspects of inheritance
Maternal Inheritance
Biparental Inheritance
Alleles of both parents are transmitted equally to progeny
All genes in nucleus undergo this
Uniparental Inheritance
Zygote obtains all plastid and mitochondrion genomes from maternal paren
Pollen Parent
Ovule Parent
Crosses
Monohybrid
Single character analyzed
Other traits not considered
Complete dominance
Traits
Dominant
Masks the recessive trait
Recessive
Other version of trait that is masked in heterozygous individual
Dihybrid
Two genes studied simultaneously
Sexual reproduction bt 2 individuals
Generations
F1
Offspring of parental
Heterozygous
2 different alleles for genes
Selfing
2 heterozygotes for same gene crossed together
When plant's own pollen fertilizes it's own eggs
F2
Offspring of F1
Parental
Parents
Homozygous
2 identical alleles for gene
Incomplete dominance
Neither parental trait dominates the other
Punnett Square 
Diagram used to predict genotypes
Test Cross
Performed to discovered genotype
Testing trait in question
Questioned individual crossed with homozygous recessive
Effects of Mutations #
Depend on
Nature
position
extent
May have no effect
Generally unimportant
Point
Small insertions
Deletions in introns
Statistically almost always harmful
Mutations
Any change in DNA
Types
Point
single base is converted to another base
Deletion
A piece of DNA is lost
Insertion
Addition of extra DNA
Inversion
A piece becomes tangled
Breaks
Put in backwards in repair
Causes
Mutagen
Physical agent
Chemical agent
Ultraviolet Light
X-rays
Radiation
Somatic
In cells that never lead to sex cells
Semiconservative replication
Each DNA strand acts as template for complementary strand
Each resulting double helix contains
1 new molecule
A conserved old one
Population Genetics and Evolution
Population Genetics
Abundance of dif alleles w/in population
Manner in which abundance
Increases
Decreases
Remains the same
Gene Pool
total number of alleles in all sex cells of all individuals of a population
Factors that cause change
Mutation
Accidents
Severe droughts for plants
Habitat destruction
Artificial Selection
Selective Breeding 
Natural Selection
Most significant factor causing change
survival of the fittest
Individuals most adapted to environment survive
Individuals least adapted to environment die
Phyletic Speciation
Gene Flow
movement of alleles physically through space
Pollen Transfer
seed dispersal
vegetative propagation
Divergent Speciation
Reproductive Isolation
alleles reach individuals in one part of range but not another
two fundamental causes
abiological reproductive barriers
Any physical, nonliving feature
Prevents two populations from exchanging genes
Biological reproductive factors
Any biological phenomenon
Prevents successful gene flow
Speciation
New species evolves from Natural Selection
Phyletic speciation
One species becomes so changed
Then considered new species
Divergent Speciation
Some populations evolve into new second species
Other population
Continue unchanged
evolve into new third species
ecology
Species today evolved from those in the past
Evolution & Origin of Life
Chemosynthesis
Most seriously considered hypothesis
Before life, Earth was different
Chemicals present could react spontaneously
Producing more complex chemicals
Continuous spontaneous reactions
No time limits
lack of free molecular oxygen
Earth before Life
Condensed from gases and dust
Hot and rocky
Mostly hydrogen
First atmosphere
Lost into space
Second atmosphere
Release of gases from
Rock Matrix
heavy bombardment by meteorites
Releasing atmospher
due to lack of molecular oxygen
Presence of powerful reducing agents
4.6 billion years ago
Convergent Evolution
two phenotypically distinct
Species
organs
Metabolisms
strongly resemble each other
Responding to similar selection pressures
cacti and euphorbias
populations and ecosystems
Plants & their Habitats
Habitat Components
Abiotic
Climate
Critically important to all organisms
Components
Temperature
rainfall
relative humidity
winds
Soil Factor
Formed by breakdown of rock
Pioneers:1st plants to invade new soil
Initially thin & identical to parent rock
Layers of thick soil
A horizon: uppermost
B Horizon: 2nd layer; zone of deposition
C horizon: 3rd layer;
composed mostly of parent rock and rock fragment
Latitude and
Altitude
Latitude contributions
At equator
Days are 12 hrs long
no seasonal variations
plants cannot measure season by photoperiod
Higher Latitudes
Summer days longer
Winter nights longer
Above Arctic and Antarctic Circles
mid-summer & mid-winter nights days 24 hours long
Intermediate & Higher Latitudes
day length=excellent indicator of season
Some species sensitive to photoperiod
Amount of light energy that strikes varies w/ this
Altitude
High altitudes
High winds
Poor soil
Much/all year is cold
Short growing season
Varying
day lengths
Dependent on latitude
Above much of Earth's atmosphere
not fully shielded by
Ozone
carbon dioxide
Oxygen
water vapor
Disturbance
Little/no impact
Examples
Fires
landslides
Snow avalanches
Floods
Biotic
The plant itself
Habitat Modification
Modifies habitat just by being in one
May be
Beneficial
Detrimental
Neutral
Other plant species
Interaction bt species
Mutualism: beneficial for both organisms
Competition: Disadvantageous for one species
Competitive Exclusion: Theory that less adapted species is excluded
Niche: species adapted to particular set of conditions
Organisms other than plants
Frugivores: fruit-eating animals
Seed dispersal(pollination): mutualism
Relationships
Commensal
One species benefits
Other unaffected
Predation
One species benefits
Other is harmed
Herbivory
Browsing
eating twigs and leaves of shrubs
Grazing
eating herbs
Pathogenic
Between plants, fungi, and bacteria
Energy in ecosystem
Plants are eaten
energy and carbon compounds move to herbivore
then to carnivore
then to decomposers
energy flow
carbon flow
The Structure of Ecosystems
Physiognomic structure
physical size, shape, & distribution of organisms in relation to
each other
physical environment
means by which plant survives stressful seasons
system of life forms
defined by C. Raunkiaer in 1934
temporal structure
changes to an ecosystem over time
time span can be short or long
species composition
trophic levels
feeding levels
primary producers
Autotrophs
1st step in food web
energy & nutrient supply for HERBIVORES
constitute primary consumers
Secondary Consumers
carnivores
prey on herbivores
omnivores exist at both levels
decomposers
fungi & bacteria
break down remains of
all types of organisms
even organisms of other decomposers
vitally important in an ecosystem
The structure of Populations
Geographic distributions
Boundaries of geo range
Limiting Factor: determines plant's health
Local Geo Distribution
Random: no identifiable pattern
Uniform: evenly spaced from neighbor
clumped: space is small/large; rarely average
Age distribution
Affects the manner in which a pop. responds to various factors in its habitat
demography: # of middle aged, young, & old people there are
Factors that affect this
generation time
length of time from birth of individual until birth of its offspring
Biotic potential
intrinsic rate of natural inrease
number of offspring that can live to reproduce
does not = # of seeds produced
r & k selection
r-selected species
produced by disturbance
pop. growth is limited by species own biotic potential
annual, early maturity, many small seeds, few chemical defenses
k-selected species
perennial, late maturity, few large seeds, many deffenses
pop. growth is governed by carrying capacity of ecosystem
deals with crowded environment, limited sources, and competition
Community Ecology
Diversity
Diversity and Scale
Species-area relationship
relationship bt area & species richness
Formula: S=cA^z
S = # of species
c and z = constants used to compare the diversity of those communities
Larger scale: more diverse
smaller scale: less diverse
species abundance distribution
large populations are more likely to survive than small
Beneficial interactions between species
mutualistic relationship
both organisms benefit
Loss still occurs
Flowers can either
produce nectar
lose pollen that is eaten
facilitation: one organism helps the other w/o receiving any benefit
Predator-Prey interactions
competition between species
when species compete for the same resource
exploitation competition
organisms eat shared resources
interference competition
one organism restricts another
one predator, one prey
primary producer plant is attacked by predator
prey dependent
predator's functional response is dependent on amount of prey
zero growth isocline
line indicating population stability
paradox enrichment
improving conditions for prey
may lead to overexploit the prey
both species will be lost
Predator selection among multiple prey
3 important factors
probability of encounter
decision by predator to attack once encounter happens
probability that an attacked prey will be eaten successfully
optimal foraging theory
examine the interactions bt the factors to understand why herbivores eat plants
optimal diet model
produced by optimal foraging theory
four different predictions
1) predators should prefer whichever prey yields the most energy per unit of handling time
2) if the high-yield prey become sufficiently scarce, then the predator would be more successful by broadening its diet to include prey that are lower in energy if they are abundant and easy to handle
3) some prey items will always be eaten if they are encountered, others will never be eaten even if easy to obtain
4) the probability that a particular plant will be eaten depends partially on the abundance of other plants that are easy to handle and have higher value
apparent competition
Looks like competition is taking place, but it isn't
Just a factor, like weather change, that causes increase on one side
Metapopulations in Patchy Environments
Metapopulation
several populations are interconnected by migration and gene flow
Model makes 4 assumptions
1) a region of the env. is composed of many discrete patches in which the species can live
2) Some patches are occupied by the species whereas other suitable patches are not
3) Empty patches will become colonized by migration from occupied patches
4) Populations within individual patches have a probability of going extinct within that patch
Interconnectedness of Species: Food Chains and Food Webs
energy flow web
how energy flows through community
food chain
direct line of consumption
food web
intercorrelation of consumption relashiptions
Classification and Systematics
Levels of Taxonomic Categories
Species: most fundamental level
Lycopersicon esculentum
Esculentum = species epiphet
The word that distinguishes this species only from the other species of the genus lycopersicon
Genera: Closely related species grouped together
Singular: Genus
Difficult to categorize
All have common ancestors
Monophyletic: natural
Unnatural: polyphyletic
members evolve from different ancestors
May resemble each other as result of convergent evolution
Family (aceae) : level above genus
Composed of one or several genera
Levels above family
Order
Class
Division
Kingdom
Taxon
General way of referring to these groups
Asteraceae
Fabaceae
Aracaceae
Paceae
Brassicaceae
Apiaceae
Cladistics
Method of analyzing these phylogenetic, evolutionary relationships
Synapomorphies (homologous features)
Features similar to each other because they have descended from a common ancestral feature
Homoplasies (analogous features)
Features that resemble each other; related by descent from common ancestral genes
Understanding Cladograms
Cladogram: diagram that shows evolutionary patterns by means of a series of branches
Node: each point at which a cladogram branches
Clade: Any node and all of the branches that lead from it
Cladograms & Taxonomic Categories
Only unit w/ objective definition = species
Informal Names
Basal Angiosperms
Eudicots
Other types of Classification Systems
Artificial Classification System
several key characters are chosen as the basis of classification
Typically have goal of easy plant identification w/ obvious characters
Classification Systems for Fossils
Combines features of both artificial and natural systems
Goal is to understand evolution of fossil and identify relatives and ancestors
Form genera: all fossils w/ the same basic form/structure are classified together
The Major Lines of Evolution
1st major event was start of life
About 3.5 billion years ago
2nd event: conversion of prokaryotes to eukaryotes
Grade Classification
Old classification of protista
Kingdom Protista: Organism similar to that of early eukaryotes
Kingdom Plantae:
From these, the major evolutionary lines that diverged
simple plants w/ neither seeds nor vascular tissues
Plants that do not produce seeds but do have xylem and phloem
seed-bearing vascular plants
Taxonomic Studies
No species is exactly alike another
Research is to look for
New Plants
New info about existing plants
Isotypes
way of avoiding recurrence of disaster by spreading to many herbaria around the world
Type specimen
single preserved plant that truly carries the name
Nonvascular Plants
Characters of Nonvascular Plants
Many have stomata
Bodies composed of parenchyma
Do not have vascular tissue
Multicellular sporangia and gametangia
almost exclusively terrestrial and have cuticle over much of body
Hepatophyta, Bryophyta, and Anthocerotophyta
Concepts
Plants divided into those that
have neither vascular tissues nor seeds
Nonvascular plants
Bryophytes
Have both vascular tissue and seeds
spermatophytes
Have vascular tissue but no seeds
Vascular cryptogams
Division Bryophyta: Mosses
Gametophyte Generation
Morphology
gametophores: leafy stems of moss plants
grow close together, tightly appressed and forming dense mounds
Grow from apical meristems
Water Transport
Conducted along exterior of moss stems by capillary action
Hydroids
cells of innermost cortex
Leptoids
cells that resemble sieve cells
Rhizoids
small, multicellular trichome-like structures that penetrate the surface of the substrate
Development
gametophore begins when a spore germinates and sends out a long, slender chlorophyllous cells
Then undergoes mitosis and produces a branched system of similar cells
this network= protonema
Reproduction
Antheridia
microgametangia
short stalk
outermost layer of sterile cells
inner mass of cells that differentiate into sperm cells
produce sperm
Archegonia
megagametangia
case shaped w/ long neck
hollow neck @ maturity
single egg located @ base
Produce eggs
Sporophyte Generation
all mosses are homosporous
Foot: small bulbous tissue
developed from archegonium
Capsule
Simple apical sporangium
Seta
Narrow stalk bt foot & sporangium
all moss sporophytes have this
operculum
caplike lid
Separates from the rest of the sporangium as cells are torn apart
Peristome teeth
exquisitely complex teeth
resulted from elaborate and precise cell breakage
respond to humidity
Bending outward and opening the sporangium when the air is dry
bending inward and trapping the spores when the air is humid
calyptra
layer of cells derived from the neck of the archegonium
Metabolism & Ecology
Some mosses are tolerant of desiccation
thin plants suffer the most
larger plants are better off
water and air do not effect quickly
Division Hepatophyta: Liverworts
Gametophyte Generation
Hepatic gametophytes
leafy liverworts
Greatly resembles that of a moss
thin leaves on a slender stem
thallose liverworts
Less like moss
Not leafy at all
flat and ribbon like
heart shaped and bilaterally symmetrical
Thallus
body without roots, stems, and leaves
Liverwort gametophores may be bisexual or unisexual
Gametophore stem grows by an apical cell with 3, 4, or 5 sides
Sporophyte Generation
most have sporangium covered in
Foot
seta
calyptra
lacks a columella
all are homosporous
elaters: single, elongate cells w/ spring-shaped walls
Division Anthocerotophyta: Hornworts
Hornworts: group of small, inconspicuous thalloid plants
grow on moist soil, hidden by grasses and other herbs
Gametophyte Generation
internally have numerous chambers
thin along edges, thick in center
shaped like ribbon or heart
might also grow outward irregularly, forming a disk
uniquely, a special mucilage chamber forms near the upper surface
cells grow into it and become antheridia
Sporophyte Generation
no seta or discrete sporangium
meristem continuously produces new tissues
large number of spores produced by each sporophyte
antheridia does not arise from surface cells
Vascular plants w/o seeds
Early Vascular Plants
Rhyniophytes
Characteristics
naked stems
epidermis with cuticle
cortex of parenchyma
simple bundle of xylem composed of tracheids
Cooksonia: genus of extinct plants
equal dichotomous branching
both branches equal size and vigor
Xylem structure of early vascular plants
two types of xylem organization
protostele
in both, center is solid mass of xylem with no pith
endarch protostele
protoxylem located in center
metaxylem differentiates on the outer edge of xylem mass
exarch protostele
metaxylem located in center of xylem mass
protoxylem on edges as several groups next to the phloem
Later evolved stele
siphonostele
pith is present in center
Occurs in stem of ferns and seed plants
Zosterophyllophytes
small herbs w/o secondary growth
3 characteristics make them distinct
lateral sporangia, not terminal
sporangia opened transversely along top edge
xylem was an exarch protostele
protoxylem on outer margin
metaxylem in center
The Microphyll Line of Evolution:
Lycophytes
Morphology
lycophytes
large enations; up to 4cm long
contained single well-developed trace of vascular tissue
Microphylls
enations in Lycophyta
vascular cambium cells can't undergo radial longitudinal division
makes them dif. from pines
Heterospory
necessary precondition for evolution of seeds
cones/strobili
compact groups of sporangia clustered together
The megaphyll Line of Evolution:
Euphyllophytes
Trimerophytes
features that separate them from rhyniophytes
Overtopping
most important
ability of one shoot to grow for a longer time than the other shoot that resulted from the branching
Pseudomonopodial branching
single main trunk rather than a series of dichotomies
Origin of Megaphylls (Euphylls)
3 distinct types
1) leaves on gametophytes of nonvascular plants
2) enations/microphylls of zosterophyllophytes and lycophytes
3) megaphylls: leaves that evolved from branch systems and are present in all seeds plants, ferns, and equisetophytes
Telome Theory: summarizes megaphyll evolution
Telomes
ultimate twigs, those of last dichotomy
Equisetophytes
one genus, several genera of extinct plants
15 extant species
Horsetails
Scouring rushes
living plants are all herbs
no secondary growth
usually less than 1 m tall
Ferns
can be found in almost any habitat
appeared in Devonian period
mostly all homosporous
Monilophytes 
two sister clades
euphyllophytes are united by 3 synapomorphies
1) their roots have exarch xylem
2) they have megaphylls
3) they have a 30-kilobase inversion in the large single-copy region of their plastid DNA
The Term "Vascular Cryptogams"
Informal name
also often called ferns and fern allies
name indicates they have vascular tissue
because they lack seeds, their reproduction is hidden
Lack
seeds
Flowers
Fruits
Etc
Seed plants w/o Flowers
Division Progymnospermophyta:
Progymnosperms
Evolution of Seeds
Chauleria
Earliest known progymnosperm with heterospory
from Middle Devonian Period
Approx. 390 million years ago
Megasporangium Structure
surrounded by layer of integument
large micropyle
hole in integument
allows sperm to swim to the egg after megaspore develops into megagametophyte and produces eggs
microspores evolved into pollen grains
Pollen chamber
holding area where microspores settled
Aneurophytales
This order contains
Aneurophyton
Protopteridium
Proteokalon
Tetraxylopteris
Triloboxylon
Eospermatopteris
stature varies
shrubs to large trees
up to 12 m tall
Structure
vascular cambium
secondary growth
Primary xylem of stems is protostele
Little webbing bt ultimate branches
Archaeopteridales
more derived progymnosperm
trees up to 8.4 m tall
structure
abundant wood
secondary phloem
stems
siphonostele
pith surrounded by a ring of primary xylem bundles
Heterosporous reproduction
Megaspores up to 300 micrometers in diameter
Microspores up to 30 micrometers in diameter
Structure
megaphyllous leaves
Both secondary xylem and phloem
no seed
no ovule precursors
Gave rise to another line of gymnospermous plants
Cycadophytes
Classified as three divisions
Pteridospermophyta
seed ferns
all extinct
Cycadophyta
cycads
extant
Cycadeoidophyta
cycadeoids
all extinct
Division Pteridospermophyta:
Seed Ferns
Earliest appeared in Upper Devonian Period
Form a grade rather than a clade
level of evolution
all descendants of common ancestor, regardless of their level of evolution
any woody plant with fern-like foliage
bore seeds instead of sori on its leaves
Thought to have evolved from Aneurophytales
both had 3-ribbed protostele
Division Coniferophyta: Conifers
50 genera and 550 species
all conifers
trees of moderate to gigantic size
have pollen cones and seed cones
most are woody
Never
vines
herbs
annuals
have bulbs or rhizomes
Always simple needles or scales
most leaves are perennial
wood lacks vessels
phloem lacks sieve tubes
Pines
two types of shoot
long shoots
tiny papery leaves
short shoots
long needle leaves
xeromorphic characters of leaves
thick cuticle
sunken stomata
cylindrical shape
Pollen cones
simple cones
single short unbranched axis
bears leaves called cone bracts
Seed cones
Compound cones
shoot w/ axillary buds
megasporophylls fuse laterally
forming ovuliferous scale
Division Cycadophyta: Cycads
Frequently confused with
Ferns
Palm trees
Structure
Stout trunk
covered with bark and persistent leaf bases
pinnately compound leaves
short plants
less than 1 or 2 m tall
stems
thick cortex
small amount of manoxylic wood
tracheids are long and wide
rays are massive
support provided by tough leaf bases
produce seed and pollen cones on separate plants
highly prized ornaments
not good with cold weather
Division Cycadeoidophyta:
Cycadeoids
all extinct
features almost identical to cycads
only subtle differences bt the 2
stomatal complexes
leaf trace organization
cones contain both microsporophylls and megasporophylls #
Division Gnetophyta
3 groups of enigmatic plants
Ephedra
40 species
Welwitschia mirabilis
only species
Gnetum
30 species
Gnetum
mostly vines or small shrubs w/ broad leaves
native to
Southeast Asia
Tropical Africa
Amazon Basin
Ephedra
tough shrubs and bushes
common in
desert regions in northern mexico
southwestern United States
dry mountains in South America
leaves reduced and scale like
Welwitschia
few living plants exist in
deserts of South Africa
Cultivation
short, wide stem
only two leaves
grow perennially from basal meristem
too young to know clearly how it evolved
cones
seed
compound and contain extra layers of tissue around ovules
pollen
compound and contain small bracts
Division Ginkgophyta:
Maidenhair Tree
fossilized remains are found almost everywhere
only species in its division
structure
stout trunk
many branches
wood
like that conifers
lacks vessels and axial parenchyma
leaves
broad
dichotomously branched veins
both short and long shoots
reproduction
dioexious
gymnospermous
no cones produced
ovules
occur in pairs
large
develop 3-layered seed coat
pollen produced in an organ that resembles a catkin
Flowers and Reproduction
Asexual Reproduction
Fragmentation
Most common type
Large plants grow to several meters in length
individual parts become self-sufficient b establishing adventitious roots #
if middle portions die, the ends become separated and act as individuals
Inflorescences and Pollination
inflorescence
many flowers grouped together
give collective visual signal to pollinators
2 basic arrangements
determinate inflorescences
only limited potential for growth
apex is converted to a flower, ending its possibilities for continued growth
indeterminate inflorescences
lowest flowers open first
new flowers still being initiated at apex
Sexual Reproduction
The Plant Life Cycle
(Humans)Diploid adults have sex organs that produce haploid sex cells
gametes
sperm
eggs
zygote
fertilized egg
More complex than human life cycle
Sporophyte phase/generation
trees
shrubs
herbs
sporophytes are always diploid
have organs with cells capable of undergoing meiosis
meiosis results in spores
Difference between spores and gametes
Spores
cannot undergo syngamy
undergoes mitosis
grows into haploid gametophyte
sporophytes form haploid plant
Gametes
can fuse with other gametes
syngamy
fertilization
form diploid sporophyte
mammalian gametes are of two types
small sperm cells
swim
microgametes
large eggs
megagametes
Don't swim
heteromorphic generation
dibiontic life cycle
sporophyte and gametophyte are easily distinguishable
alternation of generations:
life cycle with two generations
embryo and seed development
cotyledons primordia grow into these
suspensor: pushes embryo deep into endosperm
Flower structure
Never wood
usually stem w/ leaf-like structures
pedicel: flower stalk
receptacle: very end of axis
where other flower part is attached
4 types of floral appendages
sepals #
lowermost, outermost of the four
thickest, toughest, waxiest
all sepals together form calyx
modified leaves that surround and enclose other parts
petals
above sepals on the receptacle
collectively known as corolla
stamens
Above petals
collectively known as androecium
2 parts
filament
its stalk
anther
where pollen is produced
carpels
constitute the gynoecium
highest level of receptacle
3 main parts
2) style
elevates stigma to a useful position
3) ovary
where megaspores are produced
1) stigma
catches pollen grains
complete flowers
have all 4
typically have 3,4, or 5 more appendages of each
incomplete flowers
lack one or more type
gametophytes
Microgametophyte
males
Megagametophyte
females
fertilization
plasmogamy: fusion of protoplasts of gametes
Karyogamy: fusion of the nuclei
fruit development
3 distinct layers in growth
2) mesocarp
middle layer: flesh
3) endocarp
innermost layer: may be tough like pit of cherry or may be thin
1) exocarp
outer layer: skin/peel
Flower Structure & Cross-Pollination
wind pollinated flowers
entire flower tiny
ovaries need no special protection
sepals often reduced/absent
mutations that prevent formation of petals is advantageous
attracting pollinators is unnecessary
pollination aided by growth pattern of plant population
Animal-Pollinated flowers
very important in evolution
most flowers are radial
some flowers are bilateral
Monoecious and Dioecious Species
essential organs
produce critically important spores
imperfect flowers
lack one or both essential organs
perfect flower
has both essential organs, may lack sepals and/or petals
nonessential organs: do not produce spores
sepals and petals
Monoecious
cattails
corn
clusters of fertilized flowers
Dioecious
marijuana
dates
willows
4 types of plants
microgametophytes
staminate
sporophytes
carpellate sporophytes
stigma and pollen incompatibility
compatibility barriers: chemical reactions bt pollen and carpels
prevent pollen growth
stamen and style maturation times
self-fertilization can be prevented if anthers and stigmas mature at different times
when stigma and style become mature, there may be no living pollen left in the flower
all pollination is effected by younger flowers just opening their anthers
not very effective means of ensuring cross pollination
Cross-Pollination
pollination of carpel by pollen from different individual
ovary position
inferior
can result if receptacle tissue grows upward around ovary
epigynous
superior
no fusion to ovary occurs
ovary is above other flower parts
hypogynous parts
Fruit Types and Seed Dispersal
True Fruits and Accessory Fruits
True Fruit
fruits containing only ovarian tissue
Accessory Fruit
false fruit
any nonovarian tissue is present
Simple fruit
fruit develops from a single ovary
fruit develops from fused ovaries of one flower
aggregate fruit
separate carpels of one gynoecium fuse during development
raspberries
multiple fruit
figs
mulberries
pineapple
all individual fruits of an inflorescence fuse into one fruit
Classification of Fruit Types
1st method
emphasis is placed on whether the fruit is
dry 
not typically eaten by natural seed-distributing animals
Further Classification
Dehiscent fruits
break open and release seeds
indehiscent fruits
do not break open and release seeds
fleshy 
eaten during natural seed distribution process
mostly indehiscent
both processes are taking in and producing energy. They have many different ways of going about doing this.
mutations lead to many different species. Sometimes these are advantageous.
Sometimes they are disadvantageous