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methane gas was converted into other simple carbon compounds.
Compounds combined to form simple molecules and then more complex molecules.
oldest are 3.5 billion years old.
resemble present day prokaryotes
-organic molecules of biological origin.
-difficult to find
-hydrocarbons derived from fatty acid tails of lipids were found in ancient rocks.
1. colonization of land by plants followed by gradual cooling and abrupt glaciation 488 to 444 million years ago.
2. vascular plants diversification concurrent with second glaciation 400 to 360 million years ago.
domain archaea, domain eubacteria, domain eukarya.
All form a clade (all related)
-nuclear membrane allows for increased complexity in eukaryotes.
-Golgi apparatus and endoplasmic reticulum facilitate intracellular transport.
-single cells to colonies to true multicellularity.
- evolved multiple times.
- allows for cellular specialization
-critical evolutionary milestone
-heterotrophs that absorb nutrients.
-have a number of different cell types.
-cell walls contain chitin.
-some have a dikaryon stage.
-undergo nuclear mitosis
-have small, amorphous structures spindle plaques.
-spindle plaques form spindle apparatus within the nucleus.
involves the fusion of two haploid hyphae of compatible mating types.
-fusion immediately results in the diploid cell (2n)
-others, have a dikaryotic stage (1n+1n) before parental nuclei form a diploid nucleus
by secreting digestive enzymes into substrates or food sources.
- fungi absorb organic molecules that were broken down by external digestion.
-fungi are absorptive heterotrophs.
-some fungi break down cellulose and lignin.
-some fungi are carnivorous
a type of microspordia
-may cause disease in immunosuppressed patients.
-infect host with spores, which contain a polar tube.
-infects intestinal and neuronal cells, leading to diarrhea and neurodegenerative disease.
aquatic, flagellated fungi; closely related to ancestral fungi.
a type of blastocladiomycetes.
-water mold, haplodiplontic life cycle, female gametes secretes phereomone to attract male gametes, giant mitochondria in zoospores
-common bread mold
-a few human pathogens
-a zygosporangium is produced, within which a diploid zygospore develops.
-Meiosis occurs during germination of zygospore-release haploid spores
-Hyphae produce clumps of erect stalks, called sporanngiospores.
-tips form sporangia with spores
-spore germination products monokaryotic hyphae which grow into a monokaryotic mycelium, or primary mycelium.
-different mating types of monokaryotic hyphae may fuse producing a dikaryotic mycelium, or secondary mycelium.
-the badidiocarps are formed entirely of secondary mycelium
-include bread yeasts, common molds, and many plant pathogens.
-also includes cup fungi and morels
-break down glucose into ethanol and CO2.
-used to make bread, beer, wine, Saccharomyces cerevisisae
Penicillium (Penicillin & Blue Cheeses)
Aspergillus (Soy Sauce and Soy Paste)
-pathogens and parasites benefit at the expense of their host.
-commensals benefit one partner but do not harm or benefit the other.
-mutualistic relationships benefit both partners.
-Fusarium spp. (vomitoxin)
-Aspergillus flavus (Aflatoxin)
-protection from desiccation by a waxy cuticle and stomata.
-evolution of leaves to increase photosynthetic surface area.
-shift to dominant vertical diploid generation.
-vascular tissues to carry water with in plant body/tracheophytes have tracheids.
-produces haploid spore by meiosis.
-diploid spore mother cells undergo meiosis in sprorangia and produces 4 haploid spores.
-spores develop innto first cells of gametophyte generation.
-spores divide by mitosis.
-produce gametes by mitosis
-gametes fuse to form diploid zygote.
-zygote develops into first cell of next sporophyte generation.
As more complex plants evolved:
the diploid stage became ______.
gametophyte was _____.
and sporophyte became _____.
the dominant stage of the life cycle.
was reduced in size.
became nutritionally independent.
small, dependent gametophyte and large sporophyte.
-primary water and mineral conducting tissue.
-also conducts inorganic ions such as nitrates, and supports the plant body.
-typically includes fibers and parenchyma in rays
-protect and feed embryo.
-introduce a dormant phase in the life cycle, "stop the clock"
protected by integument; and extra layer or 2 of sporophyte tissue.
-hardens in to seed coat.
-dispersed by wind or a pollinator.
-external water not needed
plants with "naked seeds"
the ovule is exposed on a scale at pollination
-pines, spruces, firs, cedars, and others.
-coastal redwood -tallest tree.
-bristle pine-oldest living tree
-thick cuticle and recessed stomata to reduce water loss.
-canals with resin to deter insect and fungal attacks.
pollen tubes reach archegonium and discharges contents.
-the sperm unites with egg=zygote.
-other sperm degenerates.
-slow growing gymnosperms of tropical and subtropical regions.
-the sporophytes resemble palm trees.
-have the largest sperm cells of all organisms.
-only gymnosperms with vessels in xylem.
-contain 3 genera (welwitschia, epherdra, gnetum
-ovules are enclosed in diploid tissue at the time of pollination.
-the carpel develops into fruit.
-modified stems bearing modified leaves
-primordium develops into a bud at the end of the stalk called a pedicel.
-pedicel expands at the tip to form a receptacle, to which other parts attach.
- flower parts are organized in circles called whorls
ovary- swollen base containing ovules, later develops in to a fruit.
-stigma- tip where pollen lands
-style- neck or stalk
- maintain dormancy under unfavorable conditions.
-protect vunerable young plant
-provide food for embryo until photosynthesis begins.
-facilitate dispersal of the embryo
-ingestion and transportation by birds or other vertebraes.
-hitching a ride with hooked spines on birds and mammals.
-burial in caches by herbivores
-transport by wind
-floating and drifting on water.
found in some plant cells.
additional layers of cellulose and lignin. (Increases mechanical strength of the wall).
dermal tissue- outer protective cover (wax and bark; non-living)
ground tissue- for storage, photosynthesis, and secretion.
vascular tissue- for conduction
-xylem(water and dissolved minerals)
-size of vacuoles.
-alive or dead at maturity.
-thickness of secretions found in cell walls.
-protoderm (forms epidermis)
-procambrium (produces primary vascular tissue)
-ground meristem (differentiates into ground tissue)
cork cambium-produces outer bark.
vascular cambium- produces 2 degree vascular tissue.
1. dermal- covers external surfaces, serves a protective function.
2. ground- forms several internal tissue types (photosynthesis, storage, structural support).
3.vascular- conducts water and nutrients.
-covered with a fatty cutin layer called the cuticle.
-may contain special cells, including guard cells, trichomes, and root hairs.
cellular or multicellular hairlike outgrowths of the epidermis.
made to keep leaf surfaces cool and reduce evaporation by covering stomatal openings
tubular extensions of individuals epidermal cells.
-increase the root's surface area and efficiency of absorption.
1. parenchyma (storage, photosynthesis, and secretion).
2. collenchyma (provide support and protection.
3. sclerenchyma (provide support and protection)
most common type of plant cell.
-living protoplast may live for many years.
-less specialized than other plant cells.
provide support for plant organs, allowing bending but not breaking.
-have living protoplast and may live for many years.
have tough thick walls, 2 degree cell walls often contain lignin.
-usually lack living cells at maturity
fibers (long, slender cells that are usually grouped in strands.
sclereids (variable shape, branched, may occur singly or in groups.
continuous tubes of dead cylindrical cells arranged end-to-end.
-shorter and wider than tracheids
-sieve cells (living cells that contain clusters of pores called sieve areas or sieve plates)
-sieve-tube members (more specialized and are associated with companion cells).
-zone of cell division
-zone of elongation
-zone of maturation
-columnella cells: inner
-root cap cells: outer and lateral.
-werewolf gene (suppresses root hair development)
-scarecrow gene (necessary for differentiation of endodermal and ground cells.
-contains mostly cuboidal cells, with small vacuoles and large central nuclei.
-derived from rapid division's of the root apical meristem.
-apical meristem daughter cells soon subdivide into the 3 primary tissues.
-roots lengthen because cells become several times longer than wide.
-width also increases slightly.
-no further increase in length occur above this zone.
-mature parts of root, except for increase in girth, remain stationary for life of plant.
-epidermal cells (have very thin cuticle; include root hair and nonhair cells)
-cortex (interior to the epidermis)
Parenchyma cells used for storage. (inner boundary comes endodermis & stele)
single-layered cylinder. (Impregnated with bands of suberin called the casparian strips)
spongy, air-filled roots, that emerge from mud.
have large lenticels for oxygen entrance.
also secrete large quantities of salt or block salt uptake
leaf with one vein branching from vascular cylinder of stem and not extending full length of leaf.
a shift from radial to dorsal-ventral symmetry.
increases photosynthetic surface
eudicot-netted or reticulate
contain undivided blades.
may have teeth, indentations, or lobes
blades that are divided into leaflets.
-pinnate=leaflets in pairs along an axis.
-palmate=leaflets radiate out from a common point
-palisade mesophyll (usually two rows of tightly packed chlorenchyma cells)
-spongy mesophyll (loosely arranged cells with many air spaces in between for gas exchange and exit of water vapor)
-pitcher plants: cone-shaped leaves that accumulate rainwater.
-sundews: glands that secrete sticky mucilage
-venus flytrap: hinged leaves that snap shut
initiates signaling pathway to close stomata in drought stress.
-opens potassium, chloride, and malate channels. water loss follows
-loss of leaves
-covering leaves with cuticle and wooly trichomes
-reduced number of stomata
-stomata recessed in pits on leaf surfaces
-collect oxygen and transport O2 to submerged parts
plants that live in saline soils
produce high concentrations of organic molecules in roots.
describes movement of carbohydrates in phloem.
-dissolved carbohydrates flow from a source and are released in sink.
-sources include photosynthetic tissues.
-sinks include growing root and stem tips as well as developing fruits.
-carbs enter sieve tubes thru smallest veins at source.
-sieve cells must be alive actively transport sucrose.
-water flows into sieve tubes by osmosis.
-turgor pressure drives fluid throughout plant.
-at sink, sucrose actively removed and water follows by osmosis.
-a mixture of sand, rocks, clay, silt, minerals, humus, organic matter, and microorganisms.
-soils are characterized by relative amounts of sand, silt, and clay
- soil composition determines the degree of water an nutrient binding to soil particles.
How do plants go through developmental changes?
1. plants do not need to be visited by animals to produce seed.
2. offspring are more uniform and probably better adapted to their environment.
1. separation of male and female structures in space.
2. separation of male and female structures in time.
1. begins once egg is fertilized.
2. the growing pollen tube enters the angiosperm embryo sac and releases 2 sperm cells
3. 1 sperm fertilizes the centrall cell and w/ 2 nuclei intiaties endosperm (3N) development.
4. the other sperm fertilizes the egg to produce a zygote (2N).
5. cell division (mitosis) soon follows creating the embryo.
-bulges are produced by embryonic cells, not by shoot apical meristems.
-results from changes in planes and rates of cell divisions.
-determined by microtubules and actin.
-microtubules also guide cellulose deposition as the cell wall forms around the new cell forms around the new cell.
-storage of food in the cotyledons or endosperm.
-differentiation of ovule tissue to form a seed coat.
-development of carpel wall into a fruit.
- a protoplast is produced.
-the cell then divides to form a callus
-the whole plant is reproduced.
flower and produce seeds and fruit for an indefinite number of growing seeds.
-may be herbaceous or woody
grow, flower, form fruits and seeds, and typically die within one growing season.
have 2 year life cycles .
-store energy first year and flower second year
-larger eukaryotic cells engulfed smaller photosynthetic bacteria.
-chloroplasts come from single line of cyanobacteria
-host are not monophyletic