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175 Cards in this Set

  • Front
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Prokaryotes

a type of cell lacking a membrane enclosed nucleus and membrane enclosed organelles


-unicellular and small, achieve all of life's functions within a single cell

Features of prok
chromosome in nucleoid, fimbriae, ribosomes, plasma membrane, capsule, flagella
shapes of bacteria
spherical, rod-shaped, spiral
cell wall

protects the cell, prevents bursting, maintains shape


-Bacteria made of peptidoglycan


-Archaea have polysacharides and proteins


-euks have cellulose or chitin

Gram stain

used to classify bacteria by cell wall composition


-gram positive: thick peptidoglycan(traps crystal violet)


-gram negative, less peptidoglycan and an outer membrane may be toxic, outer lipopolysacharide (crystal violet easily rinsed away, revealing red dye)

Capsule
Cell surface structure: capsule is sticky layer of polysacharide or protein: works for attachment aid or desiccation protection or protect from host immune system
Fimbriae or pili

cell surface: allow them to stick to their substrate or other individuals in a colony:


fimriae hair like protein appendages, called atttachment pili

Sex pili
longer than fimbriae that allow proks to exchange DNA
Flagellum
common structure used by proks for directional movement: can be spread over entire cell or on one or both ends, smaller than ones on euks
evolution of flaggellum

made by series of simpler proteins that lines up and continue to form up. ATP synthase of membrane line up with other transport proteins.


signal transduction proteins bind to protoflagellum linking its function to state of environment, chemotactic flagellum as proteins keep binding extending the flagellum




-video: gradual steps towards selective active transport apparatus to move proteins from the cytoplasm to the extracellular environment (some parts include atp synthase, secretin and pores); Then adhesive protein gets secreted by system but remains bound to secretin and further of this forms pilus

Irreducible complexity
some things so intricate and complex that no way that it could function if it were less complex or sophisticated. only conclusion is that products of intelligent design
Exaption

process in which existing structures take on new functions through descent with modification


example is prokaryotic flagellum

taxis

ability to move toward or away certain stimuli (motility)


chemo taxis moving toward or away from chemical signal/nutrient


phototaxis movement based on light

Nucleoid
region in the prok that contains dna genome(very small, tightly compacted and compressed)
plasmids

bacterial dna separate taht are smaller, up to 600 copies of it per cell with up to 100 nucleotides, helps confer antibiotic resistance;


can exist independently or integrated into chromosome

Genetic diversity
Rapid reproduction, mutation, and genetic recombination
Prok reproduction
reproduce quickly by binary fission; replication begins at origin of replication and both copies move toward opposite ends of cell, once replication finished, membrane grown inside, new cell wall deposited and two daughter cells
Reproduction of plasmids

for high copy, random partitioning, random segregation of plasmids into daughters,


for low copy, replication coordinated with chromosome replication, partitioned into daugter cells-----


plasmids can be passed on integrated or not integrated into the chromosome

Rapid reproduction/mutation

as quick as 1-3 hours, cold outweight earth in one day if <10 minutes; mutation rates low but because rapid, chances for mutation more likely, high diversity allows for rapid evolution



Selection for GASP phenotypes

Growth advantage in stationary phase: 5 stages:


lag, exponential growth, stationary, death, long term stationary


example: starvation by bacteria after stationary select for ability to break down amino acids for source of carbon and energy; mutation in genes can serve as basis for GASP phenotypes

Genetic recombination
combining of dna from two sources which adds to genetic diversity: done by transformation, transduction, and conjugation
Transformation:
prok cell can take up foreign dna from surrounding environment, dead cell dna enters live cell and incorporates dead cell dna in homologous region of live cell's genome
Transduction
the movement of genes between bacteria by bacteriophages. Phage invades bacteria cell and goes though viral reproduction process then when it enter lytic cycle, part of bacterial genom enters capsid of phage and when that phage attaches to new cell, the bacterial genome integrates at homologous region in new recipient cell
Conjugation
process where genetic material is transferred between prokaryotic cells, dna only transfer in one direction. Donor cell attatches to recipient through the sex pili which requires the F Factor
F factor as plasmid
The f factoris a plasmid, that cell is the F+ cell (donor) and other cell without it is F- (recipient), so that gene signals production of sex pili, and replicates plasmid with f factor and transfers the f plasmid to recipient cell so F- turns to F+, so both F+ now with the f factor
Factor in chromosome
F factor built into chromosome which is donor cell (Hfr/ high frequency recombination-bacterial chromosome) signals for production of sex pili to recipient F- cell. Hfr chromosome gets replicated completely then transfered through sex pili to F- cell then then homologous regions of Hfr chromosome integrate into recipeint chromosome, rest of hfr chromosome disappears, including the F factor so recipient cell is not a recombinant F- bacteria.
Horizontal/lateral gene transfer
movement of genes among individuals from different species instead of vertical which is parents to offspring
Photoautotrophs

get energy from light


get carbon from CO2 or HCO3- or other compounds


example: photosynthetic proks, plants, some protists

chemoautotrophs

energy from chemicals (inorganic chemicals like H2S, NH3, Fe2+)


get carbon from CO2, HCO3-


example, some proks

Photoheterotophs

get enegery from light


gen carbon from organic compounds


example: aquatic and salt proks

chemoheterotrophs
get energy and carbon from organic compounds
example: many proks, protists, fungi, animals, some plants
Obligate aerobes
proks that require O2 for metabolism/cellular respiration

obligate anaerobes
proks that are poisoned by O2 and use fermentation or anaerobic respiration for metabolism
Facultative anaerobes
proks that can survive with or without O2 for their metabolism: ex. E coli.
Nitrogen metabolism

some proks can metabolize nitrogen through nitrogen fixation where they convert N2 to NH3.


nitrogen essential for amino/nucleid acids

Metabolic cooperation

cooperation so proks can use resources they could not use as individual cells


example: cyanobacterium anabaena photosyntehic cells and heterocysts (nitrogen fixing cells) exhange metabolic products

Biolfilms

where some prok specis form coasts like mushroom and do metabolic cooperation.


Starts with some proks/ planktonic on surface then other proks come to form slime then more to form mircrocolony, multiple layers, and then form mushroom shape where some detach and revert to planktonic cells like they started to complete cycle

Chemical recycling
proks play role in recylcing of chemical elements between living and non living components of ecosystems, chemoheterotrophic proks function as decomposers, nitrogen fixing proks add usable nitrogen to environment;, proks add nitrogen, phosporus, and potassium for plant growth; proks immobilize or decrease the aviailability of nutrients
Symbiosis
ecological relationship in which two species live in close contact: larger is the host and smaller is the symbiont
mutualism
both symbiotic organisms benefit
commensalism
one organism benefits while neither harming nor helping the other in any significant way

parasitism
an organism called a parasite harms but does not kill its host. parasites that cause disease called pathogens.
The human microbiome
Bacteroides fragilis produces polysacharide A (psa) which helps keep the immune system by boosting anti inflammatory arm. PSA is presented to undifferentiated T cells and stimulates them to become regulatory T cells and tamps down inflammation T cells
pathogenic bacteria
proks cause about half of all human disease, Lyme disease which is cause by bacterium carried by ticks.
Exotoxins
secreted proteins that cause disease even if the bacteria that produced them are not present . proteins in the cytosol of cell and are secreted through wall and membrane(cholera)

endotoxins
released only when bacteria dia and their cell membranes break down; surface associated. the toxins are in the cell wall and are released when dies (salmonella)
spread of toxin genes
through horizontal gene transfer between species
toxin mechanisms of action

damage cell membrane


inhibit protein synthesis


activate secondary messenger pathways

R plasmids
plasmids that carry genes for antibiotic resistance, protects them from antibiotics. through natural selection, the bacteria with resistance increases with exposure to antibiotics.
Antibiotic resistance
starts with a lot of bacteria then exposed to antibiotics which kill bacteria causing illness and protection bacteria. the drug resistant survive then take over and grow. Then drug resistant bacteria spread resistance to other bacteria
antibiotics resistance spread
can spread in the hostpital which goes to other patients or from equipment used and when people go home, they spread. Or eating animals or plants that had antibiotics such as bushmeat
Methicillin-resistant S aureus (MRSA)
staphylococcus aureus contains genes for resistance, ability to colonize host, increased disease severity, and increased gene expression and toxin production
Bacteria and archaea but not eukarya

dont have nuclear envelope, no membrane enclosed organelles, have circular chromosomes, no mitosis, lateral gene transfer, haploid.


euks the opposite of this

Archaea and euks but not bacteria
no peptidoglycan in cell walls, introns in genes, growth of response to antibiotics not inhibited, histones on dna present. opposite for bacteria
Bacteria and euks but not archae

unbranched hydrocarbons, growth at temperature after >100C.,


oppositite for archaea

archaea extremes
extreme temperatures and pH's
Eukaryotes

most are single celled


very complex with functions carried out by organelles


have cell membrane and ribosomes like proks


but also have dna around proteins, more chromosomes and organelles

Ribosome structure
bacteria have no genes around ribosome, ukes have protein rna around it, and mammals have proetin rna, rna-rna and rna
Endosymbiosis

by lynn margulis and this radical concept.


it explainsstructure of the complex organelles and nucleus.

hans ris
discovered the similarity between chloroplassta nd cyanobacterium. they had ribosomes, similar rna, inner and out membrane, thylakoids, etcs.
dProk adaptations
evolution of photosynthesis 2.7 bya so chloroplasts descend from photosynthetic proks, and there was the oxygen revolution about 2.1 bya and increas use of O2, so mitochondra descend from aerobic heterotrophic proks
Process of endosymbiosis
start with two independent bacteria, then one engulfs the other, one lives inside the other, they benefit from arrangement, internal bacteria are passed on from generation to generation
Support of endosymbiosis
similar inner membrane, division is binary fission, dna short and circular, dna transcribe and translate own dna, ribosimes more similar to proks than euk ribosomes
Primary vs Secondary endosymbiosis
primary is prok doing phagocytosis to another prok, then secondary is when a endosymbiont cell, now a euk is eaten by a prok. this happened when green and red algae were eaten after both had eaten cyanobacteria.
Chlorarachniophytes
enguled cell(prok being eaten by another prok for endosymbiosis) enguled cell became plastid with vestigial nucleus (nucleomorph), the sequence which resemble green algae. 4 membranes: inner an douter from ancient cyanobacterium, 3rd from algae plama membrane and outer from food vaculoe
Protists
everything that is a euk but not fungi, animals or land plants
History of classifying protists

started as one of three domains (plants, protists, animals) then one of five when added fungi and monera.


then realized life was more than proks and euks, rather it was tripartite


protist before was unicellular euks


then term abandoned and just not animals, plants or fungi. protists have more diveristy than other euks

Protists diveristy
often parasites
Giardia

parasite in the gut. causes sever diahrea that is in contaminated water or good which infected cysts.


treated with metronidazole

Trypanosoma

parasitic protist which causes sleeping sickness from kinetoplastids. the host/vector is tsetse fly


have the bait and switch defense which is antigenic variation where it changes surface proteins so that way immune system can't bind to it

Plasmodium falciparum
parasitic protist that causes malaria. caused by asexual erythrocytic parasites. accumulate in infected red blood cells, dumped into bloodstream when infectd cells lyse
Process of plasmodium falciparum
first mosquito bites and injects sporozoites, then sporozoites enter hepatocytes (liver cells in human). then sporozites form merozoites and those enter red blood cells. Merozoites divide every 2-3 days then break out of rbcs and cause symptoms and infect other rbcs to form gametocytes. another mosquito bites and picks up gametocytes and those gametocyes form male gamets and fertilization occurs in digestive tract of mosquito to form zygote. Then oocyst develops after meiosis from zygote in gut wall and oocyst releases thousands of sporozoites and those migrate to mosquitos salivary glands til it bites another human repeats cycle
Algae
polyphyletic group of photosynthetic eukaryotes
Dinoflagellates

armoured cellulose plates, flagellum lies in groove. blooms cause red tides (harmful algal blooms)


produce toxins which can inhibit or kill other phytoplankton(interspecific competition). metabolic pathways responsible for toxin production still under investigation


causes organism or paralystic shellfish poisoning (alexandrium catenella), and of diarrhetic shellfish poisoning (dinophysis sp)

Diatoms/pseudo nitzchia and domoic acid

neurotoxin that causes amnesic shellfish poisoning--> short term memory loss, seizures, death. biaccumulates in shell fish and fish that feed on toxic phytoplankton...


diatomos are unicellular algae with two part glass like wall of hydrated silica, reproduce mostly asexually, major component of phytoplankton, diverse, have diatomaceous earth is fossil walls


***after they die, mayny individuals fal to ocean floor undecomposed

Harmful Algal Blooms (HAB) impact on ecosystem
loss of tourism, food sources, ecosystem damage, monitoring, accumulations
Biological carbon pump
during carbon cycle, CO2 naturally removed from atmosphere becase phytoplankton absorb it, and sequester carbo then die and take the CO2 that they sequesterd to bottom of ocean.
Iron hypothesis
by john martin that fertalizing oceans with iron because would increase popoulation of diatoms and would increase carbon sequestratin and used to mitigate global warming
Slime molds (mycetozoans)
once thought to be fungus. have two branches. plamodial slime molds and cellular slime molds
Plamodial slime molds
brightly pigmented yellow or orange. plamodium is undivided by membranes and contains diploid nuclei. extends psuedopodia through decomposing material. engulfs food by phagocytosis
Cellular slime molds

cellular slime molds form multicellular aggregates in which cells are separted by membranes. with food they act individually but without food form aggregates

Dictyostelium discoideum
experimental model for studying evolution of multicellularity. very common cellular slime mold
life cycle of cellular slime mold (dictyostelium)

asexual reproduction: solitary amoebas (n)--> aggregated amoebas--> migrating aggregate--> fruiting bodies (n)--> spores (n)--> emerging amoeba(n)--> solitary amoebas(n)


Sexual reproduction: solitary amoebas-->fertilization-->zygote(2n)--> meiosis--> amoebas(n)--solitary amoebsa

Obligate cheaters
dicty that never form stalk and cheat. may gain reproductive advantage, but they are rare in the wild becasue non cheaters aggregate with other non cheaters, cooperative behavior.
Primitive farming symbiosis
dicty has this where they engage in husbandry and stop feeding early and incorporate bacteria intro fruiting bodies and carry bacteria in spore dispersal. sometimes advantageous other times not. they will reassosciate with bacteria
fungi

diverse and widespread. essential for well being of most terrestial ecosystems because break down organic material and recycle vital nutriets. heterotrophs that feed by absorption.


secrete exoenzymes that break down complex molecules and then absorb the smaller compounds

Body structure

most are multicellular then single cells (yeasts). morphology of multicellular enhances ability to absorb nutrients.


some grow as filaments or yeasts, others do both

hyphae

tiny filaments used for absorption



mycelia:
networks of branched hyphae adapted for absorption

chitin
what fungi cell walls are made of
mycorrhizae fungi
mutually beneficial relationships between fungi and plant roots. fugni often efficient at absorbing minerals more than roots. increase water uptake and mineral absorptions. plant provides fungus with suppoly of sugar.

Haustoria
specialized hyphae that can extract nutrients from plant cells. remain separated from the plant cells cytoplasm by the plant's plama membrane.
spores
fungi produce these thourhg sexual and asexual processes to propagate themselves.
plasmogomy
union of two parent mycelia, the hyphae are attracted together by signals called pheromones and when they meet they fuse
heterokaryon

when haploid nuclei do not fuse right away and coexist in the mycelium (different nuclie)



dikaryotic

when haploid pair off two to a cell


dikaryotic meaning two nuclei

Karyogamy
nuclear fusion. hours or centuries may occur before karyogamy, the haploid fuse producing diploid cells, this diploid stage is short lived
sexual reproduction life cycle of fungi

mycelium-->plasmogamy--> heterokaryotic stage--> karyogamy-->zygote-->meiosis-->spores--> germination--> more mycelium

asexual cycle of fungi
mycelium--> spore producing structures--> spores--> germination--> mycelium
Diverse lifestyles of fungi

--decomposers/saprobes


--mutualistic symbionts (metabolic cooperation--mycorrhizae,endophytes, lichens)


--Parasites (30% of fungi are parasitic): absorb nutrients from a living host, responsiblefor 80% of plant diseases

Fungi as decomposers

efficient decomposers; perform essential recycling of chemical elements between the living and nonliving world


-keep ecosystem stocked with the inorganic nutrients for plant growth. plants need fungi for the recycling of these nutrients in the soil.

Mycorrhizae/endophytes
myrcorrhizae important in natural ecosystems and agricultures. they harber sybiotic endophyetes that live inside leaves and other plant parts. endophytes make toxins that defend plant against herbivores and pathogens. increase plant tolerance to extremes, increase plant productivity by producing more biomass of individual or community, or increase production of fertility.
Lichens

symbiotic associations of millions of photosynthetic microorganisms held in a mass of fungal hyphae.


-photosynthetic organisms can be euk algae or cyanobacteria


-fungus give lichen its overall shape and stucuter. tissues of hyphae give it its mass.


dual organisms perform asexual reproduction which is common.

types of lichens

crustose: important pioneers of new rock, physically and chemically attack rock, trap soil.


-lichens predate land plants


foliose lichen


fruticose lichen.

formation of lichens

algae or cyanobacteria occupy inner layer below lichen surface; the algae provide sugar, cyanobacteria fix nitrogen for lichen.


fragmentation of soredia



soredia
small clusers of hyphase with embedded algae
history of lichens
before 140 years ago, they thought lichens symbiosis between a single fungus and photosynthetic partner. recent research shows that it has second fungus type of yeast unrelated to first fugnus. present in integral parts of lichens.
Pathogens

30% of known fungal species are parasites, mostly on or in plants


-some fungi that attack food crops are toxic to humans

ergot of rye (claviceps purpurea)

has lysergic acid, causes ergot poisoning


the bewitched accusers of salem witch trials may have suffered hallucinations/ skin sensations from crop of fungus infected rye

other plant funguses
corn smut on corn (huitlacoches) , tar spot fungus on maple leaves, ergot on rye
mycosis
term for fungal infection in animals; but animals less susceptible to parasitic fungi than are plants
cordyceps sp.

zombie ants have fungus on the brain


ants suffer convulsions unable to climb high and stay in cool, damp leaf understory. syncs ant behavior, forcing ants to bite the stem on underside of the leaf at solar noon when sun is strongest.

archaeplastida
super group used by some scientists that includes red, green algea and land plants. red and green algae are the closest relatives of land plants.
Red algae
red color due to accessory pigment phycoerythrin that mask green of chlorophyll, green in shallow waters, black very deep. usually multicellular like seaweeds.
porphyra
foliose red alga
green algae
grass green chloroplasts, closely related to land plant, . two main groups called chlorophytes and charophytes
chlorophytes:
unicellular, colonial, and multicellular forms
similarities between green algae and land plants
multicellular, eukaryotic, photosynthetic autotrophs, cellulose cell walls, chloroplasts with chlorophylls a and b
charophytes
similar to plants because have sequence similarities, nuclear and chloroplast gene sequences, charophytes resemble algal ancestors of plants
why plants above waterline

advantages: more sunlight, co2, nutrients. fewer herbivores and parasites


disadvantages: scarcity of water, dessiccation, gravity and lack of structural support

derived traits of plants

alteration of generations and multicellular, dependent embryos,


walled spores produced by sporangia


multicellular gametangia,


apical maristems

Alteration of generations

alternating between haploid and dipoids.


plus multicellular, dependent embryos

gametophyte
haploid structure taht produces gametes by mitosis
sporophyte
structre that formed from the fusion of gametes, and this produces haploid spores by meiosis
Diploid embryo
retained within tissue of female gametophyte; nutrients are transferred from parent to embyro through transfer cells

embryophytes
land plants; embryo depends on parents
multicellular gametangia
the organ that produces gametes. contains the femal and male gametophytes
archegonia
female gametangia that produces eggs and is the site of fertilization
antheridia
male gametangia that produces and releases sperm
Sporangia

the multicellular organ that sporophytes are located in and that produces spores.


within sporangia, diploid cells called sporocytes undergo meisis to make spores.


spore walls made out of sporopollenin, help with resistance to harsh envrionments


-->helps form walled spores

Apical meristems
how plants sustain their continual growth--localized regions of cell division. cells from meristems have different tissues and have specialized functions for above and below ground
Cuticle

covers the epidermis. cuticle consists of wax and other polymers.


helps prevents desiccation and resistance to microbial attack

origin and diversification of plants
land plants about 475millin years ago as see from fossilized spores and tissues, the sprores were grouped
vascular tissues
origin 425 million years ago
byrophytes
nonvascular plants, not a monophyletic group. the relationships are unresolved
Seed plants

origin 305 million years ago


form a clade that can be further divided

seed
an embryo and nutrients surrounded by a protective coat
gymnosperms
the naked seed plants, such as conifers

angiosperms
flowering plants
lifecycles of nonvascular plants including mosses

dominated by gametophytes, gametophytes are longer-lived than sporophtes, sporophytes only present part of the time

phyla of bryophytes
liverworts (hepatophyta), mosses (bryophyta), hornworts (anthocerophyta), bryophyte and bryophyta are different.
lifecycle of bryophytes
start with spores, then spore buds, then individually in own cycles, form male and female gametophyte (anterhidia and archegonia) then eggs and sperm meet up and fertlizie within archegonium. now diploid, form zygote then embryo, then sporophyte then sporangium givies off haploid spores after meiosis
importance of mosses

sphagnum or peat mosses, forms extensive deposits of partially decayed orangic material called peat, peat is source of fuel


sphagnum is importan resovoir of organic carbon and soil carbon, drop in water level in peatlands could release stored CO2 to atmoshere

seedless vascular plants including ferns
diversified during the devonian and carboniferous periods, vascular tissue allowed plants to grow tall. have flaggellated sperm that restricts them to moist environements
life cycle of seedless vascular

opposite of bryophytes, the sporophytes is the dominant, larger generation


start with spores to gametophyte on or below soil level. with anteridium and archegonium on same structure, sperm reaches egg and fertilizes, forms zygote, new sporophyte that has sporangium and meiosis releases spores.

xylem

in vasuclar plants; conducts water and minerals.


has dead cells and tracheids


lignin that strenthens the water conducting cells and provides structural support

phloem

in vascular plantt, disributes organic products and consists of living cells,

roots
organs that anchor vascular plants, enable plants to absorb water and nutrients from soil
significance of seedless vascular platns

ancestors of lycophytes, horestails and ferns is that they grew to great heights during devonian and carboniferous period (400-300 million years ago), formed forests


increased photosynthesis and removed co2, contributed to global cooling at end of carboniferous period, decaying plants of carboniferous forester turned to coal

seed plants
360 million years ago, seed has embryo and nutirents with protective coat. allowed for domestication of plants 8k years ago and permanent settlements
seeplants adaptations
reduced gametophytes, heterospory, ovules, and pollen
advattages of reduced gametophyte

gametophytes are microscopic, gamteophytes develop within walls of spores retained within tissues of the parent sporophyte


-protectin from uv rays and desiccation, also get engery from sporophyte

homosporous
most seedless vascular plants that produce one type of spore that develops into bisexual gamtertophyte that can develop eggs and sperms
heterosporous
some seedless vascular and alll seed plants that produce megaspores which give rise to femal gametophytes and microspores give rise to male gametophytes, separate sporangiums
ovules

structure that developes within ovary and has female gametophyte, consistes of mega sporangium, mega spore, and protective integuments

integument
layer of sporophyte tissue contributes to structre of seed plant

fertlization
the union of haploid gametes to produce dipolid zygotes
pollen grains
microspores develop into this which contain male gametophytes

pollenation
transfer of pollen to part of a seed plant contianing the ovules. eliminates need for film of water and can be dispersed great distances by air or animals. if pollen grain germinates, dives rise to pollen tube that discharges two sperm into femal gametophyte and within ovule
evolutionary advantages of seeds
develop from whole ovule, seed is sporophyte embryo, along with its food supply, packaged in a protective coat, can remain dormant for years till favorable conditions for germination. transported long distance by wind or animals
gymnosphersm
naked seeds such as ones on cones. not enclosed by ovaries and are exposed on modified leaves that form cones. appear 305 million years ago. 4 phyla (cycadophyta, gingkophyta, gentophyta, coniferophyta)

cydads from cycadophyta phylum
flourished in mesozoic era, age of cycads, 300 extant species, unchanged for 300 million years ago

angiosperm evolution
diverege 305 million years ago, originated 140 million years ago. a
adaptations of angiosperms
flowering plants with fruits and flowers. most widespread and diverse. classified under one phylum calls anthophyta

flower

angiosperm structure for sexual reproduction. has specialized shoot with sepals that enclose flower, petals to attract pollinators, stamesn produce pollen with antersn and filamnet


and carpels with stigma style and ovary

archaefrutcus sinensis
125 million year old chinese angiosperm with anters and seeds but not petals and sepals. had bulbous strucuters
mimicry
when flowers mimic the shape of a bug to attract pollinators to the flower

orchid mantis
pollinator decption, uses mimicry of a flower to attract bugs that it can eat
fruits
help disperse the seeds of angiosperms, consists of mature ovary, seed deelps from ovule and the wall thickens to form fruit, fruit protects the dormant seeds and aid in their dispersal
evolutionary relation between angiosperms and animals
animals influence the evolution of plants and vice versa
succulence
plants ability to store water, can be in specialized stems like cacti or euphorbia, or specialized leaves like aloe or agave
cacti

have spines make of sharp wood outgrowth from leaves.


have reduced surface area so dont lose water from transpiration contanct with air.


large network of roots

convergent evolution of succulents
in america with cacti, euphorbia in africa. have similar desert envvrionments for succeulant traits and distant locations
lithops
plant with each leaf tip that has a region of clear lens like cells that allow light to penetrate to the photosynthetic tissues underground. conserve moisture, hide from grazing tortoises, avoid high temps and light intensities