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230 terms

cumulative science

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protects the developing flower
what is the function of the sepals of a flower?
the colors and shapes of the petals attract insets and other animals. these organisms ensure that pollination occurs.
what is the function of the petals of a flower?
the male reproductive parts that help produce new flowers
what is the function of the stamens of a flower?
produces pollen
what is the function of the anthers of a flower?
the thin stalk that supports the anthers. it also gives nutrition to the anther
what is the function of the filaments of a flower?
sperm cells that help pollination occur.
what is the function of the pollen grains of a flower?
the female reproductive organ.
what is the function of the pistil of a flower?
the sticky tip of the pistil that attracts pollen.
what is the function of the stigma of a flower?
connects stigma to the ovary
what is the function of the style of a flower?
it protects seeds while they develope.
what is the function of the ovary of a flower?
a plant structure in seed plants that contains an egg cell.
what is the function of the ovules of a flower?
1) the angiosperm produces flowers. 2) inside the ovary, an egg cell is produced in each ovule of the pistil. the cells in the anther produce pollen grains. 3) the pollen grains are trapped in the stigme. 4) the pollen grains produce a pollen tube that grows into the ovule. a sperm cell moves through the pollen tube and joins with the egg cell. 5) the ovule develops into a seed. the ferilized egg becomes the seed's embryo. other parts of the ovule develop into the seed coat and the seed's stored food. 6) the ovary and other structures develop into a fruit that encloses the seeds. the fruit helps in seed dispersal. 7) a seed grows into a new plant.
what are the steps of an angiosperm life cycle?
an angiosperm that has two seed leaves. ex. violets, roses, dandelions, oak, maple trees... # of petals: a multiple of 5 and 4. shape of the leaves: wide with viens that branch. vascular tissue arrangement: in a circle.
what is a dicot? characteristics?
the waxy, waterproof layer that covers the leaves and stems of some plants.
define cuticle?
contain chloroplats that trap the energy in sunlight for photosynthesis
what is the function of the upper leaf cells in a leaf?
the many spaces between the lower leaf cells temporarily store carbon dioxide and oxygen.
what is the function of lower leaf cells in a leaf?
the vascular tissue through which nutrients and water absorbed by the plants flows from the roots up into the leaves and stems.
what is the function of xylem?
the food made during photosynthesis enters the phloem and travels from the leaves to the stems and roots.
what is the function of phloem?
the internal transporting tissue in some plants that is made up of a tubelike structure.
what is vascular tissue?
a fertilized egg produced by the joining of a sperm and egg cell.
what is a zygote?
the joining of a sperm cell and an egg cell.
what is fertilization?
the thin, root-like structure that anchors a moss and absorbs water and nutrients for the plant.
what is a rhizoid?
fern leaves. underneath the spores can be found.
what is a frond?
a seed leaf that stores food.
what is a cotyledon?
the plant structure that contains a young plant inside a protective covering.
what is a seed? (are you kidding me?!)
the outer covering of a seed.
what is a seed coat?
the process by which water evaporates from a plant's leaves.
what is transpiration?
the early growth stage of the enbryo.
what is germination?
the layer of cells in a plant that produces new phloem and xylem cells.
what is the cambium?
a plant that produces seeds that are not enclosed by a protective covering.
what is a gymnosperm? (remember, people tend to wear less clothing in GYMs)
a plant that produces seeds that are enclosed in a protective structure.
what is an angiosperm? (ANGles wear more clothing)
the growth response of a plant toward of away from a stimulus.
what is tropism?
the plant hormone that speeds up the rate growth of plant cells.
what is auxin?
1) obtainig water and nutrients from the soil. 2) retaining water with cuticles. 3) transporting water, food, and munerals using vascular tissue. 4) support and strength by vascular tissue. 5) reproduction.
what are 5 plant adaptations for living on land?
1) sporophyte 2) grow into gametophyte produce sperm/egg 3) fertilization. 4) zygote 5)embryo grows into sporophyte
what is the life cycle of moss?
tiny particles produced by plants that contain the microscopic cells that later become sperm cells.
what is pollen?
a plant structure in seed plants that contains an egg cell.
what is an ovule?
an angiosperm that has only one seed leaf. ex. corn, wheat, rice, lilies, tulips. # of petals: a multiple of 3. shape of leaves- parallel veins. vascular tissue arrangement: scattered randomly
what is a monocot? characteristics?
1) production of naked seeds 2) scale-like/needle-like leaves. 3) deep growing root systems.
what are 3 characteristcs of gymnosperms?
1) low growing. 2) have no vascular tissue. 3) obtain water and minerals directly from soil. 4) 3 types of nonvascular plants are liverworts, mosses, and hornworts. 5) no true roots, leaves and stems.
what are characteristics of nonvascular plants?
water, wind, animals (digestive system/sticking to fur)
3 methods of seed dispersal.
means an organism with cells that contain nuclei and other cell structures.
eukaryotes
means the process by which plants and some other organisms captures light energy and use it to make food from carbon dioxide adn water
photosynthesis
the process of grouping things based on their similarities.
classification
a branch of biology that classifies living organisms and names them.
taxonomy
the first scientist to classify organisms. a. he grouped animals according to their environment-land, water, air. b. today we use his method of "observationh" and creating subgroups.
aristotle.
called the founder of modern taxonomy. he divised a naming system called binomial nomenclature.
Linnaeus.
the naming system organized by Linnaeus. in this, each organism is given a two-part name.the first part being its genus, the second being its species. these two characteristics put together make up an organisms scientific name.
binomial nomenclature.
is a classification grouping that contains similar, closely related organisms. this is also the first part of an organism's scientific name.
genus
is a group of similar organisms that can mate and produce fertile offspring in nature. it is also the second part of an organism's scientific name.
species
is a series of paired statements that describe the physical characteristics of different organisms.
taxonomic key
is used to help classify organisms (biological classification)
taxonomic or dichotomous key.
means ancient bacteria
archaebacteria
they are unicellular and have no nucleus. this type of bacteria is found in yogurt. helps fight off bad bacteria.
eubacteria
are tiny organisms that are mostly unicellular. some examples are paramecium and ameba
protists
are mushrooms, mold, and mildew. they feed on dead or decaying organisms. they are decomposers.
fungi
they are multicellular and are able to make their own food (autotrophs)
plants
organisms in this group are more complex than plants. they are multicellular and are heterotrophs. this means they do not make their own food and rely on an outside food source.
animals
cells without a nucleus. ex. bacteria
prokaryotes
an organism that lives on or in another organism and causes harm
parasite
is the organism that the parasite lives and feeds on or in.
host
the round shaped type of virus. ex. staphylococcus aureus (strep throat)
spherical
is a long whip-like structure used for movement.
flagellum.
a poison that can harm an organism
toxin
is a reproductive process that involves only one parent and produces offspring that are identical to the parent.
asexual
a form of asexual reproduction. the cell first duplicates its genetic material and then divides into two separate cells. each new cell gets its own complete copy of the parent cell's genetic material as well as some of the parent's ribosomes and cytoplasm
binary fission
an illness that is passed from one organism to another
infectious disease
a chemical that kills bacteria without harming the cells of the host
antibiotic
where one bacterium transfers some of its genetic material into another bacterial cell through a thin, threadlike bridge that joins the two cells. after the transfer, the cells separate.it results in the production of new bacteria which are genetically different than the parent cells.
conjugation
small, nonliving particle that invades and then reproduces inside a living cell. it does not grow, isnt made up of cell(s). does not respond, cannot make food or take it in, and doesnt produce wastes. but it can reproduce and has DNA. it also acts like a parasite.
virus
requires oxygen to break down food and survive
aerobic respiration
a virus that infects bacteria that has a robot like shape.
bacteriophage
one billionth of a meter. viruses are measured using this unit of measure
nanometer
after entering a cell, an active virus immediately goes into action. the virus' genetic material takes over the cell's functions, and the cell quickly begins to produce the virus' proteins and genetic material. then these parts assemble into new viruses. like a photocopy machine left in the "on" position, the invaded cell makes copy after copy of new viruses. when it is full of new viruses, the host cell bursts open and releases the new viruses.
active viruses
the small, rounded, thick-walled, resting cell that forms inside a bacterial cell. it allows bacteria to survive harsh conditions (heat, freezing).
endospore
the genetic material of these viruses enters a host cell. then its genetic material becomes part of the cell's genetic material. the virus does not appear to affect the cell's functions. the virus' genetic material may stay in this state for a while. then, for reasons, that scientists do not yet fully understand, the virus' genetic material suddenly becomes active. it takes over the cell's functions like the active viruses do. in a short time, the cell is full of new viruses and it bursts open to release them. ex. cold sores.
hidden virus
eubacteria that live in soil break down dead organisms are called decomposers
decomposers
substance that stimulates the body to produce dhemicals that destroy viruses or bacteria. ec. polio, mumps, rubella, smallpox, measles, chicken pox, tetanus.
vaccine.
animal-like protists that use flagella to move. most of them have on to eight flagella. many of them live inside the bodies of other organisms. ex. intestines of termites. they digest the wood that the termites eat, producing sugars for themselves and for some termites.
zooflagellates
the small nucleus in ciliates that control reproduction
micronucleus
interaction between 2 species where at least one benefits.
symbiosis
a funnel-like indentation lined with cilia. the cilia move water containing food into the vacuole that forms at the end of the oral groove.
oral groove
ce on a layer of slime that it produces. most have more than one host. ex. malaria:two hosts are involved-humans and a species of mosquitoes. spreads when mosquito bites a person with malaria, infected+ bites a healthy person.
sporozoans
when both partners benefit from living together, the relationship is a type of symbiosis called mutualism
mutualism
spores produved in fruiting bodies/vary in appearance also called spore case
sporulation
small hair-like structures used for movement. it sweeps food particles into the oral groove and it senses the environment.
cilia
temporary bulges of the cell membrane that fill with cytoplasm. it means "false foot". they from when the cell membrane pushes outward in one location. it is used to engluf food particles through a process called phagocytosis.
psudopod
when diatoms die, their cell walls collect on the bottoms of oceans asnd lakes. over time, they form layers of a coarse material called diatomaceous earth. this makes a good polishing agent. ex. toothpastes, many household scouring products as well as in swimming pool filters, and insecticides.
diatomaceous earth
the large nucleus in ciliates that controls the cell's activitiews
macronucleus
the process where psuedopods engulf food particles
phagocytosis
branching, threadlike tubes. they are found in multicellular fungi and transport food, water, and minerals throughout the fungi.
hyphae
yeast cells use the sugar in things for food and produce carbon dioxide gas as they feed. the gas forms bubbles, which makes things like dough to rise. without it, bread would be flat and solid. it is also used in wine so alcohol and carbon dioxide can be produced.
yeast
small particles, like those of water, pass easily though the cell membrane into the cytoplasm so things like amebas have problems. if the excess water were to build up inside the cell, the ameba would burst. fortunately, amebas hlave a contractile vacuole, a structure that collects the extra water and then expels it from the cell.
contractile vacuole
unicellular yeast cells undergo a form of asexual reproduction called budding. in budding, no spores are produced. instead, a small yeast cell grows from the body of a large, well-fed parent cell in a way that might remind you of a bud forming on the branch of a tree. the new cell then breaks away and lives on its own.
budding
the most abundant substance in the body
water
the process by which your body breaks down food into small nutrient molecules
digestion
nutrients that are not made by living things are called minerals.
minerals
molecules that act as helpers in a variety of chemical reactions within the body.
vitamins
nutrients that contain nitrogen, as well as carbon, hydrogen, and oxygen are called proteins.
proteins.
like carbohydrates, fats are high-energy nutrients that are composed of carbon, oxygen and hydrogen.
fats
the substances in food that give the raw materials and the energy needed by the body are called nutrients
nutrients
a flap of tissue that seals off the windpipe, preventing food from entering it.
epiglottis
a muscular tube that connects the mouth to the stomach
esophagus
involuntary waves of muscle contraction that push food through the digestive system
peristalsis
the physical breakdown of food. ex. chewing
mechanical digestion
in chemical digestion, chemicals produced by the body break foods into their smaller chemical building blocks.
chemical digestion
the tiny finger shaped structures that cover the inner surface of the small intestine are called villi. nutrient molecules pass from the small intestine into the bloodstream through the villi.
villi
is the last section of the digestive system. it is about one and a half meters long. it runs up the right-hand side of the abdomen, across the upper abdomen, and then down the left-hand side. the large intestine contains bacteria that feed on the material passing through.
large intestine
almost all chemical digestion and absorption of nutrients takes place in the small intestine. it is 6 meters long, it makes up 2/3 of the digestive system
small intestine
is one whose trait always shows up in an organism when the allele is present.
dominant allele
is one whose trait is hidden or masked when a dominant allele is present.
recessive allele
is when an organism always produces an offspring with the same trait as the parent. ex. short plants produce shor offspring/tall plants produce tall offspring.
purebred
different forms of a gene. individual alleles control the inheritance of traits from each parent.
alleles
an organism that has 2 differnt alleles for a trait (heterozygous)
hybrid
characteristics that an organism can pass on to an offspring
traits
the passing of traits from parent to offspring
heredity
the scientific study of heredity
genetics
is the likelihood that a partifular event will occur, not necessarily what will occur. ex. coin toss-heads or tails are the possible outcomes. 1 in 2 probability. **the more tosses you make, the closer your actual results will be to the prdicted results of the prbability. the results of one toss do not affect the results of the next toss.
probability
is a chart that shows all the possible combinations of alleles that can result from a genetic cross
punnett square
is its physical appearance or its visible traits. ex short or tall.
phenotype
is its genetic makeup or its allele combination. ex. Tall- pure tall=TT. hybrid tall (hides the recessive trait)=Tt
genotype
means that an organism has 2 identical alleles for a trait. ex. pure for a trait=>TT or tt
homozygous
means that an organism has 2 different alleles for a trait. hybrid=Tt
heterozygous
alleles are neither dominant or recessive. both traits appear in the offspring. ex. erminette chickens-black and white feather alleles are codominant. both colored feathers are present.
codominance.
to take in food
ingestion
removal of indigestible material
egestion
the break down and absorption of food nutrients
digestion
the absorption and distribution of materials throughtout an organism
transport
cellular respiration that requires oxygen is called aerobic
aerobic respiration
cellular respiration that does not require oxygen is called anaerobic
anaerobic respiration
removal of waste products from chemical reactions is called excretion.
excretion
chemical reactions that combine small molecules to form larger molecules
synthesis
the ability of an organism to respond to chances in its surrounding is regulation
regulation
an organism's cell increases in cize or total number of cells through growth
growth
the process to produce offspring that are similar to the parents is reproduction
reproduction
an organisms cells use energu to do their jobs. ex grow, repair injured parts, to digest foods
cell's energy use
all cells of living things are made up of chemicals- water (most abundant chemical), carbohydrates (source of energy), proteins and lipids (are the building blocks), and nucleic acids (generic material in DNA)
chemicals of life.
means that all organisms are made of small building blocks called cells. cell: is a basic unit of stucture and funtion in an organism. unicellular: is made up only one cell. multicellular: made of many cells.
cellular organization
stimulus-a change in surroundings that causes a reaction. ex. change in temperatures. responce-is the reaction to a stumulus. ex: you jump when scared.
response to surroundings
protects the cell and regulates what substances enter the cell. included in the plant and animal cell.
cell membrane
surrounds th4e cell membrane, giving it a box-like shape. made of cellulose. included in the plant cell
cell wall.
produces most of the cell's energy. "power house" included in the plant and animal cell
mitochondria
recieve materials from the endoplasmic reticulum and send them to other parts of the cell. they also release materials outside the cell. included in the animal and plant cell
golgi body
capture energy from sunlight and use it to produce food. "contain clorophil" included in the plant cell
cloroplast
produce proteins, they may be attached to the outer surfaces of the endoplasmic reticulum or they may float free in the cytoplasm. included in the plant and animal cell
ribosome
carries materials from one part of the cell to another. included in the plant and animal cell
endoplasmic reticulum
contain chemicals that break down food particles and worn-out cell parts. included in the animal cell.
lysosome
carries genetic imformation that controls inherited characteristics such as eye color and blood type. included in the animal cell.
chromosome
directs all of the cell's activities, incluing reproduction. "brain of cell or control center" found in the plant and animal cell.
nucleus
can contract or shorten, by doing this, muscle tissue makes parts of your body move.
muscle tissue
provides support for your body and connects all its parts. bone is one kind of connective tussue; its strength and hardness support your body and protects its internal structures. fat is also a connective tissue. it pads part of your body, provides insulation from cold, and stores energy.
connective tissue
the body's tendency to keep an internal balance. homeostasis is the process which an organism's internal environment is kept stable in spite of changes in the external environment.
homeostasis
the spaces in bone contain connective tissue called marrow
marrow
produces the body's blood cells, as a child, most of your bones contained red bone marrow. as a teenager, onle the ends of your femurs, skull, hip bones, and sternum contain red marrow
red marrow
this marrow stores fat, which serves as an energy reserve
yellow marrow
voluntary muscle-skeletal muscle. it is striated. they are attached to the bones of your skeleton. these muscles provide the force that moves your bones. a tendon is a strong connective tissue that attaches muscle to bone. involuntary muscles- smooth muscle is non-striated. they are found inside many internal organs. they are involved in digestion especially and work slowly, therefore tire more slowly. they produce a churning action. the action mixes food with chemicals produced by your stomach. the cardiac muscle is striated and doesnt get tired.
muscle tissue types
the cardiovascular system is made up of the heart, blood vessels, and blood.
cardiovascular system
the upper chanbers of the heart. they recieve blood that comes to the heart.
atrium
the lower chambers of the heart. they pump blood out of the heart.
ventricle
arteries carry blood away from the heart.
arteries
they carry blood back to the heart
veins
materials are exchanged between the blood and the body's cells. one process in which materials are exchanged between the blood and the body cells is diffusion.
capillaries
the largest artery in the body is called the aorta.
aorta
a red blood cell is made mostly of hemoglobin, which is an inro-containing protein that binds chemically to oxygen molecules.
hemoglobin
they take up oxygen in the lungs and deliver it to cells elsewhere in the body
red blood cells
they fight disease. they last for months or even years. they have nuclei. they are bigger than red blood cells. there is about one white blood cell for every 500 to 1000 red blood cells.
white blood cells
pieces of cells. when a blood vessel is cut, platelets collect and stick to the vessel at the site of the wound. the platelets release chemicals that start a chain reaction. this series of reactions eventually produces fibrin. the fiber net traps blood cells. as more and more platelets and blood cells become trapped in the net, a blood clot forms. a scab is a dried bloot clot on the skin surface.
platelets
the process in which oxygen and glucose undergo chemical rections inside cells to release energy
respiration
the air sacs found at the end of the bronchioles where fas exchange takes place
alveoli
dome shaped muscle used in breathing
diaphragm
the voice box
larynx
the throat. it is the only part of the respiratroy system that is shared with another system--the digestive system.
pharynx
the windpipe.
trachea
the passage that direct air into the lungs
bronchi
oxygen=>capillaries=>blood`
breathing in
carbon dioxide=>blood=>capillaries=>alveoli
breathing out
air enters nose=>into the pharynx=>to the trachea=>into the bronchi=>to the bronchioles=>alveoli
the path of air
a group of similar organisms that can mate and produce offspring are species
species
adaptation is a trait that helps an organism survive and reproduce
adaptation
the gradual change in a species over time is called evolution
evolution
a well tested concept that explains a wide range of observations is a scientific theory
scientific theory
the process by which individuals that are better adapted to their environment are more likely to survive and reproduce than other members is called natural selection
natural selection
the preserved remains of an organism that lived in the past is called a fossil.`
fossil
petrified fossils are formed when minerals replace the remains, changing them into rock
petrified fossils
the empty space that remains when some hard parts become dissolved. the empty space has the same shape as the organism or part that was buried.
mold
the type of fossil that forms when a mold becomes filled in with minerals that harden. the cast takes on the shape of the mold creating a replica of the organism or part.
cast
formed when a dark sticky form of oil seep up from underground causing animals to get stuck.
tar pits
insects have been preserved in the sticky sap from evergreen trees. it hardens forming amber with the insect perfectly preserved.
amber
is used to determine which fossil is older but not an actual age.
relative dating
determines actual age. fossil's nearby rock contains radioactive elements that break down (decay) into different elements over time. half life of these elements means the time it takes for half of the atoms to decay. they compare how much of the radioactive element is in the sample and the amount of the enw element, then calculate the age.
absolute dating
one theory that proposes that evolution occurs slowly but steadily. tiny changes in a species gradually add up to major changes over very long periods of time.
gradualism
overproduction-more offspring are produced than there are resources for. competition-food and resources are limited, offspring must compete with each other--indirectly happens. variations-are any difference between individuals of the same species. ex. newly hatched turtles are able to run faster than other turtles. some variations make certain species better adapted to their environment more likely to survive and reproduce. over time the offspring will inherit the new variation as an allele and future generations will have this "helpful trait". only genes or traits that are inherited can be acted on by natural selection.
3 things that afdfect natural selection
a new species can form when a group of individuals remains separated from the rest of its species long enough to evolve different traits. they can be separated by water, mountains, volcano, or canyons.
how do new species form? how are they separated?
they compare the pattern of the nitrogen bases. the more similar the pattern, the more closely related the organisms are. also, scientists compare the amino acids within the protein of the organisms
name 2 ways that scientists use similarities in DNA to determine how species can be related.
he believed evolution occurs slowly but steadily. tiny changes in a species gradually add up to major changes over very long periods of time.
how did darwin think that evolution occured?
the cell cycle is the regular sequence of growth and division that cells undergo.
cell cycle
relication is the process when a cell makes a copy of its dna
replication
the stage during which the cell's nucleus divides into 2 new nuclei is mitosis.
mitosis
a rod-shaped cellular structure made of condensed chromatin; contains DNA, which carries the genetic information that controls inherited characteristics such as eye color and blood type.
chromosome.
one of the identical rods of a chromosome
chromatid
is the center of the chromatid that holds the 2 strands together
centromere
is the process that completes cell division. during cytokinesis, the cytoplasm divides, distributing the organelles into each of the two new cells.
cytokinesis
the structure of DNA looks like a twisted ladder
double helix
adenine-thymine. guanine-cytosine
4 nitrogen bases of DNA
stage 1. the cell grows to its mature size. the cell makes a copy of its DNA. the cell prepares to divide into two cells
interphase
stage 2a. the chromatin in the nucleus condenses to form chromosomes. structures called spindle fibers form a bridge between the ends of the cell. the nuclear membrane breaks down/disappear.
prophase
stage 2b. the chromosomes line up across the center of the cell. each chromosome attaches to a spindle fiber at its centromere, which still holds the chromatids together.
metaphase
stage 2c. the centromeres split. the two chromatids separate. one chromatid moves along the spindle fiber to one end of the cell. the other chromatid moves to the opposite end. the cell becomes stretched out as the opposite ends pull apart.
anaphase
stage 2d the chromosomes begin to stretch out and lose their rodlike appearance. this occurs in the two regions at the ends of the cell. a new nuclear membrane forms around each region of chromosomes.
telophase
stage 3. the cell membrane pinches in around the middle of the cell. eventually, the cell pinches in two. each daughter cell ends up with the same number of identical chromosomes and half the organelles and cytoplasm.
cytokinesis
theory that species evolve during short periods of rapid change. these periods of rapid change are separated by long periods of little or no change. species evolve quickly when groups become isolated and adapted to new environments.
punctuated equilibria.
similar structures that related species have inherited from a common ancestor. ex, ancient whale fossil-had legs to walk on land compared with today's whale shows how humans and whales share a common ancestor.
homologous structures
is a diagram that shows how scientists think different groups of organisms are related.
branching tree
most compounds that contain carbon
organic compounds
compounds that do not contain the element carbon
inorganic compounds
large organic molecules made of carbon, hydrogen, oxygen, nitrogen, and in some cases, sulfur
proteins
contain carbon, hydrogen, and oxygen.
carbohydrates
building blocks of proteins are amino acids. there are 20 different amino acids. they can be combined in different ways to form thousands of different proteins. the kinds of amino acids and the order in which they link together determines the type of protein
amino acid
a type of protein. they make chemical reactions occur. the names for them usually end in ase. ex. lactase (breaks down lactose)
enzymes
the tough, yet flexible, material that meakes up the cell wall of cells
cellulose
contain carbon, hydrogen, and oxygen. the building blocks are 3 fatty acids and 1 glucerol. they include fats, oil and waxes. lipids provide energy and can be stored under the skin of animals. also, part of the cell membrane (structural).
lipids
contain carbon, hydrogen, oxygen, nitrogen, and phospherous. they are the building blocks are nucleotides. two kinds of nucleic acids are DNA and RNA.
nucleic acids
these tiny cell structures carry out specific functions within the cell.
organelles
the process by which molecules move from an area in which they are highly concentrated to an area in which they are less concentrated.
diffusion
the diffusion of water molecules through a selectively permeable membrane is called osmosis. osmosis is important to cells because cells cannot function properly without adequate water.
osmosis
active transport is the movement of materials through a cell membrane using energy
active transport
the movement of materials through a cell membrane without using energy is called passive transport
passive transport
first the cell membrane surrounds a particle. once the particle is engulfed, the cell membrane pinches off and forms a vacuole within the cell. the cell must use energy in this process.
engulfing
the process by which cells break down food molecules (glucose) and release the energy
respiration
taproot and fibrous
2 types of root systems