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male structure


holds pollen (fuzzy)


holds anther


attracts pollenators


protects bud


female structures


catches pollen


holds stigma and ovary together


holds the egg

double fertilization

A mechanism of fertilization in angiosperms, in which two sperm cells unite with two cells in the embryo sac to form the zygote and endosperm.

seed coat

tough outer coat-protects embryo and sperm


stores and transfers nutrients to embryon
monocots: 1 cotyledon
dicots: 2 cotyledons


protects seend once dormant

seed dispersal

burr: sticks to animals
fruit: eaten by animals that passes through digestive tract
water: water currents

seed germination

the plant embryo begins to grow (favorable conditions)

hooked shoots: dicots

middle of shoot pushes up first
protects shoot as it comes through soil
(2 cotyledons)

sheath: monocots

another tube that creates a path for the plant to grow
(1 cotyledon)


the first moment the plant is above ground

environmental conditions

cacti live in dry, desertous areas and there isn't much rainfall-so they have to store H2O in their roots

other adaptations

long periods of cold: won't germinate in winter
brush fire: less competiotion for resources
natural selection: survive in extreme environments with adaptations

vegetative reproduction

a sexual reproduction in plants/with human help

fibrous roots

monocots: roots are spread out which will increase exposure to soil (minerals/nutrients) and water


dicots: one large central root with smaller brances
(like carrots)


points where leaves are attached to the stem


portions of stem between nodes

stem tissue

runs vertically in the stem to transport nutrients and minerals from the roots to the leaves
food is also transported down from the leaves to the shoots

terminal buds

buds on the top of the stem


buds off the sides of the stem


complete life cycle (germinate, grow, produce flowers and seeds, and die) in a single growing season


2 years and usually only flowers in 2nd year


live/reproduce in multiple years

dermal tissue

"skin" of the plant
(epidermis-protects young plants)

vascular tissue

structural support
transports H20, minerals, nutrients, organic molecules between roots and shoots
(xylem: transports H20 up to leaves)
(phloem: transports food to roots-down)

ground tissue

storage and support
makes up most of a young plant and function in photosynthesis
(root cortex)

parenchyma cells

abundant cells-fruits
thin cell walls with large central vacuoles
(function: food storage, photosynthesis and respiration)

collenchyma cells

-young stems/petioles have this below the surface
-unevenly thick cells walls & grouped in strands/cylinders
-(f: provide support for growing plants
provide some flexibility)

sclerenchyma cells

-supports the plant, thick cell walls,lignin-rich cell walls
-grow and die within a mature part of a plant; leave their lignin-rich cells behind creating a "skeleton"
-(f: "skeleton" that supports plant, specialized for support


tissue that generate new dermal, vascular, and ground tissue in plants throughout their lives

apical meristem

meristem in the tips of roots and shoots

root cap

the very tip of the root (protects the cells of the apical meristem)

apical meristem functions

1) replaces the cells of the root cap that are scraped away by the soil
2) produces cells for primary growth


inherited characteristic that improves an organism's ability to survive and reproduce in a particular environment

HMS Beagle

ship Darwin sailed on

Galapagos Islands

where Darwin first developed his evolution ideas

Charles Lyell

gradual and observable geologic processes such as erosion could explain the physical features of nature-Earth was older than previously thought

Thomas Malthus

struggle for exsistence
population is growing too fast for food production

descent with modification

descendants of the earliest organisms spread into various habitats over millions of years-in these habitats they accumulated different adaptations to the diverse ways of life

natural selection

process by which induviduals with inherited characteristics well-suited to the environment leave more offspring on average than other induviduals (result is adaptation)


preserved remains or marking left by organisms that lived in the past

fossil record

chronological collection of life's remains in the rock layers, recorded during the passage of time


species that no longer exsist

homologous structures

Structures in different species that are similar because of common ancestry

vestigial structures

remnant of a structure that may have had an important function in a species' ancestors, but has no clear function in the modern species


a group of induviduals of the same species living in the same area at the same time


refers to differences among members of the same species

artificial selection

selective breeding of domesticated plants/animals to produce offspring with genetic traits that humans value

gene pool

consists of all the alleles (alternative forms of genes) in all the induviduals that make up a population

frequency of alleles

how often certain alleles occur in the gene pool


evolution on the smallest scale-generation to generation change in the frequency of alleles within a population

Hardy-Weinberg Equilibrium

populations that don't undergo change to their gene pools are not presently evolving

genetic drift

a change in the gene pool of a population due to chance

Bottleneck Effect

reducing the size of a gene pool due to chance (natural disasters)

Founder Effect

when a few induviduals colonize on an isolated island, lake, or somewhere else new to habitat-the smaller the colony, the less genetic makeup there is to represent the gene pool of the larger population (chance reduces genetic variation)

gene flow

the exchange of genes with another population


a change in an organism's DNA


the contribution that an induvidual makes to the gene pool of the next generation compared to the contributions of other induviduals-HAS to be able to reproduce

biological species concept

defines a species as a population or group of populations whose members have the ability to breed with one another in nature and produce fertile offspring


encompasses more dramatic biological changes-origin of new species, extinction of species, and the evolution of major new features of living things-over a LONG period of time


the origin of new species

reproductive isolation

some kind of barrier that keeps 2 species from interbreeding


different breeding seasons


two similar species may have different courtships or mating behaviors (dances, sounds etc.)


one lives on land, the other in babies for them

physically incapable

an elephant and a mouse just can't do it...

geographic isolation

seperation of populations as a result of geographic change or dispersal to geographically isolated places

adaptive radiation

such evolution from a common ancestor that results in diverse species adapted to different environments

punctuated euilibrium

species often diverge in spurts of relatively rapid change


the study of the processes of multicellular organisms as they develop from fertilized eggs to fully formed organisms

geological time scale

organizes Earth's history into 4 distinct ages known as the Precambrian, Paleozoic, Mesozoic, and Cenezoic (then divided into periods)

radiometric dating

based on the measurement of certain radioactive isotopes in objects


the number of years it takes for 50 percentof the original sample to decay

continental drift

landmasses on different plates change position relative to each other as a result of this movement

mass extinctions

the fossil record reveals that Earth's history has long periods of relative stability broken up by comparitively brief episodes of great species loss


involves the identification, naming, and classification of species


a two-part name to each species

phylogenetic tree

the group that species are classified in (groups in groups)
kingdom, phylum, class, order, family, order, family, genus, species

convergent evolution

a process in which unrelated species from similar environments have adaptations that seem very similar

analogous structures

similar adaptation that result from convergent evolution


each evolutionary branch in a phylogenic tree

derived characteristics

unique features that unite the organisms as a clade


a phylogenic diagram that specifies the derived characters of clades

five-kingdom system

monerans, protists, plants, fungi, animals

three domain system

bacteria, archaea, eukaryotes

embryo sac

the resulting structure of the 3 cycles of mitosis-female gametophyte


pollen grains released from anthers land on the stigmata of flowers of the same species

pollen tube

once the pollen is on a stigmata, a pollen grain absorbs water and extends a structure-this structure grows toward the ovary through the sytle

dicot adaptation

hooked shoot tip that protects the delicate shoot by holding it downward as shoot moves through the soil

monoct adaptation

a sheath surrounding the shoot pushes straight upward \, breaking through the soil

secondary growth

growth in plant width

primary growth

growth in plant length

vascular cambium

a cylinder of actively dividing cells located between the xylem and the phloem


the secondary xylem that is laid down in the growing seasons of each year accumulates as this

cork cambium

a meristem that develops from parenchyma cells in the remaining cortex


everything outside the vascular cambium


(Function in plant) protein and nucleic acid synthesis


(FIP) protein synthesis


(FIP) nucleic acid and ATP synthesis


(FIP) protein synthesis; regulation of osmosis


(FIP) cell wall formation; enyzyme activity


clorophyll synthesis; enzyme activity

nitrogen fixation

certain species of soil bacteria convert atmospheric nitrogen to ammonia in this process


plants such as peas, peanuts, alfalfa, and beans that house their own nitrogen-fixing bacteria

nitrogen absorption

plants that can't absorb nitrogen need bacteria in the soil to do it- nitrogen must first be converted to ammonia ions or nitrate ions

nitrogen fixing bacteri

bacteria that converts nitrogen to ammonia

ammonifying bacteria

break down organic materials (feces & dead leaves)

nitrifying bacteria

converts ammonia ions to nitrate ions

root nodules

the legumes house their bacteria in these lumps found on the roots

root hairs

tiny outgrowths of the root's epidermal cells

root pressure

helps push water up the xylem and usually operates at night


a layer of cells that surround the vascualr cambium


the loss of water through the leaves due to evaporation-this generates the pull of of water up a tree


the tendancy of molecules of the same kind to stick to one another


the property of sticking together (as of glue and wood) or the joining of surfaces of different composition


long cells with tapered ends

vessel elements

wider, shorter, much less tapered cells-hollow

guard cells

a pair of these cells surround each stoma open and close the stoma by changing shape


pores in the epidermis of leaves

sieve-tube members

the ploem of vascular tissue transports sucrose and other organic componds along with water-this strem of ploem sap occurs through these chains of cells

companion cells

cells alongside sieve-tube members that provide proteins and other resources

pressure-flow mechanism

water flows from where its pressure is higher to where its lower

source to sink

phloem moves sugars from where they're made to where they are used


a plant that grows on the surface of another plant but makes all its own food through photosynthesis


plants that grow on other plants, but tap into the host plant's vascular tissue and steal their food

plant hormones

chemical messengers in plants


produced in the apical meristem
promote cell elongation (build up on the shaded side and stimulates growth beneath the tip)


stimulate cell division
produced in actively growing tissues (embyros, roots, and fruits)


stimulate the growth of stems by promoting cell division and cell elongation
also promote seed germination

abscisic acid ABA

during dormancy, this hormone inhibits celll division in buds and in the vascular cambium (halts primary and secondary growth during dormancy)
also promotes dormancy in seeds
also causes stomata to close


stimulate fruit ripening
promotes "leaf drop"


a change in plant growth due to touch


the growth of a plant part toward or away from light


a plant's growth in respins to gravity


salt-tolerant plants with adaptations such as salt-glands

circadian rhythm

a bioloigical cycle that occurs about every 24 hours


the ability to use an environmental stimulus to time seasonal activities

short-day plants

certain plants flower in the fall or winter when the dark periods exceeds a certain length

critial night length

when the dark period exceeds a certain length

long-day plants

flower in the late spring or summer when dark periods shorten

day-neutral plant

flowers when it reaches a certain stage of maturity, regardless of the length of the day or night

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