The nonliving players in an ecosystem, such as climate and nutrients.
Plant hormone that inhibits cell growth, prevents premature germination, and stimulates closing of the stomata.
Autosomal dominant form of dwarfism seen in one out of 10,000 people.
The movement of a particle across a selectively permeable membrane against its concentration gradient. This movement requires the input of energy, which is why it is termed "active" transport.
A trait that, if altered, affects the fitness of the organism. Adaptations are the result of natural selection and can include not only physical traits such as eyes and fingernails but also the intangible traits of organisms, such as lifespan.
A rapid series of speciation events that occur when one or more ancestral species invates a new environment.
adrenocorticotropic hormone (ACTH)
A hormone that stimulates the secretion of adrenal cortical hormones, which work to maintain electrolytic homeostasis in the body.
Energy-producing reactions in animals that involve three stages: glycolysis, the Krebs cycle, and oxidative phosphorylation. Requires oxygen.
Statistic that compares the relative number of individuals in the population from each age group.
Behavior that results from a conflict of interest between individuals; often involves intimidation and submission.
Organic compound that contains a gydroxyl (-OH) hunctional group.
Occurs in fungi, yeast, and bacteria. Pyuvate is converted in two steps to ethanol. regenerating two molecules of NAD+.
Carbonyl group in which one R is a hydrogen and the other is a carbon chain. Hydrophilic and polar.
Released from the adrenal gland, this hormone acts on the distal tubules to cause the reabsorption of move Na+ and water. This increases blood volume and pressure.
Transports waste products in mammals to the placenta. Later it is incorporated into the umbilical cord.
A variant of a gene for a particular character.
Interbreeding ceases because some sort of barrier separates a single population into two (an area with no food, a mountain, etc.). The two populations evolve independently, and if they change enough, then even if the barrier is removed, they cannot interpreed.
alternation of generations
Plant life cycle, so named because during the cycle, pplants sometimes exist as a diploid organism and at other times as a haploid organism.
Behavior pattern that reduces the overall fitness of one organism while increasing the fitness of another.
Functional unit of the lung where gas exchange occurs.
Compounds containing amino groups.
A compound with a carbon center surrounded by an amino group, a carboxyl group, a hydrogen, and a R group that provides an amino acid's unique chemical characteristics.
aminoacyl tRNA synthetase
Enzyme that makes sure that each tRNA molecule picks up the appropriate amino acid for its anticodon.
A functional group that contains -NH2 and that acts as a base; an example is an amino acid.
Structure formed from epiblast that encloses the fluid-filled cavity that helps cushion the developing embryo.
Enzyme that breaks down the starches in the human diet to simpler sugars such as maltose, which are fully digested further down in the intestines.
Energy-producing reactions, known as fermentation, that do not involve oxygen. It begins with glycolysis and concludes with the formation of NAD+.
Illness in which a lack of iron causes red blood cells to have a dimished capoacity for delivering oxygen.
The condition of having an abnormal number of chromosomes.
Flowering plant divided into monocots and dicots (monocotyledons and dicotyledons).
Ion with a negative charge that contains more electrons than protons.
anterior pituitary gland
Structure that produces six hormones: TSH, STH (or HGH), CTH, LH, FSH, and prolactin.
Pollen-producing portion of a plant
Male gametangia in bryophytes and ferms designed to product flagellated sperm that swim to meet up with the eggs produced by the female gametangia.
Region present at a tRNA attachment site; a three-nucleotide sequence that is perfectly complementary to a particular codon.
antidiuretic hormond (ADH)
A hormone produced in the brain and stured in the pituitary gland; it increases the permeability of the collecting duct to water, leading to more concentrated urine content.
A molecule that is foreign to our bodies and causes our immune system to respond.
Region at the tips of roots and shoots where plant growth is concentrated and many actively dividing cells can be found.
Movement of water and nutrients through the nonliving portion of cells.
Warning coloration adopted by animals that possess a chemical defense mechanism.
One of two major prokaryotic evolutionary branches. These organisms thed to live in extreme environments and include halophiles, methanogens, and thermaacidophiles.
Female gametangia in bryophytes, ferns, and gymnosperms.
Eukaryotic organism that allegedly most closely resembles prokaryotes.
Structures that carry blood away from the heart.
When humans become the agents of natural selection (breeding of dogs).
Haploid meiotic products produced by certain fungi
Region on protein synthesis machinery that holds the tRNA carrying the next amino acid.
Process by which animals take one stimulus and associate it with another.
The smallest form of an element that still displays its unique properties.
Enzyme that uses the flow of hydrogens to drive the phosphorylation of an adenosine diphosphate molecule to produce adenosine triphosphate.
Communication that involve the use of sound in the conveying of a message.
autonomic nervous system (ANS)
A subdivision of the perepheral nervous system (PNS) that controls the involuntary activities of the body: smooth muscle, cardiac muscle, and glands. The ANS is divided into the sympathetic and parasynpathetic divisions.
Ont that is not directly involved in determining gender.
An organism that is self-nourishing. It obtains carbon and energy without ingesting other organisms.
Plant hormone that leads to elongation of stems and plays a role in phototropism and gravitropism.
A longer extension that leaves a neuron and carries the impulse away from the cell body toward target cells.
When there are two or more phenotypic variants maintained in a population.
The attachment of lichen to rocks, followed by the step-by-step arrival of replacement species.
Inactivated genes on X chromosomes.
An animal that is harmless copies the appearance of an animal that is dangerous as a defense mechanism to make predators think twice about attacking.
Science that studies that studeis the inter action between animals and their environments from an evolutionary perspective.
Substance that contains bile salts, phospholipids, cholesterol, and bile pigments such as bilirubin, is stored in the gallbladder, and is dumped into the small intestine on the arrival of the food.
Help to mechanically digest fat by emulsifying it into small droplets contained in water.
Mechanism by which prokaryotic cells divide. The cell elongates and pinches into two new daughter cells.
binomial system of classification
System created by Linnaeus in which each species is given a two-word name: Genus + species (e.g., Homo sapiens).
Cycles that represent the movement of elements, such as nitrogen and carbon, from organisms to the environment and back in a continuous cycle.
Biomass represents the cululative weight of all the member at a given trophic level.
The various geographic regions of the earth that serve as hosts for ecosystems.
The entire life-containing area of a planet--all ecosystems and communities.
Living organisms of an ecosystem.
The maximum growth rate for a population given unlimited resources, unlimited space, and lack of competition or predators.
Offspring produced per a specific time period.
Mollusks with hinged shells such as oysters and clams.
As a morula undergoes its next round of cell divisions, fluid fills its center to create this hollow-looking structure.
Theory that the genes contributed by the two parents mix as if they are paint colors and the exact genetic makeup of each parent can never be recovered; the genes are as inseparable as blended paint.
A dramatic reduction in population size that increases the likelihood of genetic drift.
Tunnels that branch off the trachea that elad into the individual lungs and divide into smaller branches called bronchioles.
Tiny lung tunnels that branch repeatedly until they conclude as tiny air pockets containing alveoli
Large number of microvilli that increase the surface area of the small intestine to improve absorption efficiency.
The first land plants to evolve from teh chlorophytes. Members of this group include mosses. liverworts, and hornworts.
bundle sheath cells
Cells that are tightly wrapped around the veins of a leaf. They are the site for the Calvin cycle in C4 plants.
Photosynthetic process that alters the way in which carbon is fixed to better deal with the lack of CO2 that comes from the closing of the stomata in hot, dry regions.
A name of the light-independent (dark) reactions of photosynthesis.
CAM (crassulacean acid metabolism) photosynthesis
Plants close their stomata during the day, collecting CO2 at night, and store the CO2 in the form of acids until it is needed during the day for photosynthesis.
A protein shell that surrounds genetic material.
Organic compund used by the cells of the human body in energy-producing reactions and as a structural material. The three main types of carbohydrates are monosaccharides, disaccharides, and polysaccharides.
The movement of carbon from the atmosphere to living organisms and back to the environment in a continuous cycle.
The attachment of the carbon from CO2 to a molecule that is able to enter the Canvin cycle, assisted by rubisco.
A functional group that is hydrophilic and polar. It has a central carbon connected to R groups on either side. If both Rs are carbon chains, it is a ketone. If one R is a gydrogen and the other is a carbon chain, it is an aldehyde.
An acidic functional group (COOH). This functional group shows up along with amino groups in amino acids.
Involuntary muscle of the heart that is striated in appearance and contains multiple nuclei.
A consumer that obtains energy and nutritients through consumption of other animals.
A photosynthetic pigment.
The maximim number of individuals a population can sustain in a given environment.
Obstacle that blocks the passage of water through the endodermis of plants
Enzyme that assists in the conversion of hydrogen peroxide to water and oxygen. Found in peroxisomes.
Molecules that speed up reactions by lowering the activation energy of a reaction.
Ion with a positive charge that contains more protons than electrons.
The main body of the neuron.
A cycle that consists of four stages: G1, S, G2, and M. G1 and G2 are growth stages, S is the part of the cell cycle in which the DNA is duplicated, and the M phase stands for mitosis--the cell division phase.
This type of immunity involves direct cellular response to invasion as opposed to antibody-based defense.
Plant cell structure constructed in the Golgi apparatus composed of vesicles that fuse together anong the middle of the cell, completing the separation process.
cellular slime molds
Protists with a unique eating strategy. When plenty of food is available, they eat alone. When food is scarce, they clump together and form a unit.
Polysaccharide composed of flucose used by plants to form cell walls.
Wall that functions to shape and protect cells. Present in plant but not animal cells.
central nervous system (CNS)
The CNS is made up of the brain and the spinal cord. The CNS controls skeletal muscles and voluntary movement.
The concentration of sensory machinery in the anterior end of a bilateral organism.
Portion of the brain that controls functions such as speech, hearing, sight, and motor control. Divided into two hemispheres and four lobes per hemisphere.
Portion of the brain that controls functions such as speech, hearing, sight, and motor control. Divided into two hemispheres and four lobes per hemisphere.
The uterus connects to the vaginal opening via this narrowed region.
A heritable feature, such as flower color, that varies amond individuals.
Stop points throughout the cell cycle where the cell verifies that there are enough nutrients and raw materials to progress to the next stage of the cycle.
Mammals and insects communicate through the use of chemical signals called pheromones.
The coupling of the movement of electrons down the electron transport chain with the formation of ATP using the driving force provided by a proton gradient. Seen in both photosynthesis and respiration.
Autotrophs that produce energy through oxidation of inorganic substances.
Polysaccharide that is an important part of the exoskeletons of arthropods such as insects, spiders, and shellfish.
A photosynthetic pigment.
Green algae that are probably the common ancestors of land plants.
The site of photosynthesis and energy production in plant cells and algae.
Accepted to be the common ancestor of the animal kingdom.
Refers to the selection of mates by one sex (in mammals, it is usually females who exercise choice over males).
Chamber used in scientific experiments to study kinesis.
Steroid that is an important structural component of cell membranes and serves as a precurson molecule for steroid sex hormones.
Formed from the trophoblast, it is the outer membrane of the embryo and the site of implantation onto the endometrium. It contributes to formation of the placenta in mammals.
The raw material that gives rise to the chromosomes (genetic material is uncoiled).
Condition in which a piece of one chromosome is attached to another, non-homologous chromosome.
Error in chromosomal replication that results in the repetition of a genetic segment.
Condition in shich a chromosome separates and reattaches in the opposite direction.
chronic myelogenous leukemia
A cancer affecting white blood cell precurson cells. In this disease, a portion of chromosome 22 has been swapped with a pice of chromosome 9.
Enzyme that cuts protein bonds in the small intestine.
Structures that beat in rhythmical waves to carry foreign particles and mucus away from the lungs.
A physiologic cycle that occurs in time increments that are roughly equivalent to the length of a day.
class I histocompatability antigens
The surface of all the cells of the human body, except for red blood cells, have these antigens, which are slightly different for each individual. The immune system accepts any cell that has the identical match for this antigen as friendly. Anything with a different major histocompatibility complex is foreign.
class II histocompatibility antigens
Antigens found on the surface of the immune cells of the body. These antigens play a role in the interaction between the cells of the immune system.
Type of associative learning that Ivan Pavlov demonstrated with his experiments involving salivation in dogs.
Delevloping embryo divides; cytoplasm is distributed unevenly to the daughter cells while the genetic information is distributed equally.
Groove formed, in animal cells, between the two daughter cells; this groove pinches together to complete the separation of the two cells after mitosis.
Final stable stage at the completion of a succession cycle.
Scenario in which individuals live in packs that are space out from each other.
Both alleles express themselves fully in a heterozygous organism.
A triplet of nucleotides that codes for a particular amino acid.
coefficient of relatedness
Statistic that represents the average proportion of genes that two individuals have in common.
Fluid-filled body cavity found between the body wall and the gut that has a lining and is derived from teh mesoderm.
Animals that contain a true coelum.
Fungi that do not contain septae.
The mutual evolution between two species, which is exemplified by predator-prey relationships.
Protective structure found around a grass seedling.
Live plant cells that provide flexible and mechanical support.
One organism benefits from the relationship while the other is unaffected.
A collection of populations of species in a given geographic area.
Describes a cell that is ready to accept foreign DNA from the environment.
Both involved are harmed by this kind of interaction. The two major forms of competition are intraspecific and interspecific competition.
Condition in which an inhibitor molecule resembling the substrate binds to the active site and physically blocks the substrate from attaching.
A protein that coats cells that need to be cleared, stimulating phagocytes to ingest them.
Elements are combined to form entities called compoinds.
Process by which heat moves from a place of hight temperature to a place of lower temperature.
Gymnosperm plants whose reproductive structure is a cone.
The transfer of DNA between two bacterial cells connected by appendates called sex pili.
conservative DNA replication
The original double helix of DNA does not change at all; it is as if the DNA is placed on a copy machine and an exact duplicate is made. DNA from the aprent appears in only one of the two daughter cells.
Heat transfer caused by airflow.
Characters are convergent if they look the same in two species, even though the species do not share a common ancestor.
Two unrelated species evolve in a way that makes them more similar. They both respond the same way to some environmental challenge, bringing them closer together.
Area that produces a thick cover for stems and roots. It produces tissue that replaces dried-up epidermis lost during secondary growth.
Cells produced by the cork cambium that die and form a protective barrier against infection and physical damage.
Bridge that connects the two hemispheres of the brain.
Outer region of the kidney or adrenal gland.
Structure that provides nutrients for a developing angiosperm plant.
This syndrome occurs with a deletion in chromosome 5 that leads to mental retardation, unusual facial features, and a small head. Most die in infance or early childhood.
Also referred to as "crossing over." When the homologous pairs match up during prophase I of meiosis, complementary pieces from the two homologous chromosomes wrap around each other and are exchanged between the chromosomes. This is one of the mechanisms that allows offspring to differ from their parents.
Those being hunted adopt a coloring scheme that allows them to blend in to the colors of the environment.
Waxy covering that protects terrestrial plants against water loss.
Waxy coat that protects plants.
cyclic light reactions
Pathway that produces only ATP and uses only photosystem I.
Protein that accumulates during interphase; vital to cell cycle control.
cystic figrosis (CF)
A recessive disorder that is the most common lethal genetic disease in the United States. A defective version of a gene on chromosome 7 results in the excessive secreation of a thick mucus, which accumulates in the lungs and digestive tract. Left untreated, children with CF die at a very young age.
The physical separation of the newly formed daughter cells during meiosis and mitosis. Occurs immediately after telophase.
Plant hormone that promotes cell division and leaf enlargement, and slows down the aging of leaves.
Provides support, shape, and mobility to cells.
Number of deaths per time period.
Patterns that can cause a predator to think twice before attaching. For example, some insects may have colored designs on their wings that resemble large eyes, making individuals look more imposing than they are.
A reaction in which two compounds merge, releasing H2O as a product.
A piece of the chromosome is lost in the developmental process.
Scientists whgo study the theory and statistics behind population growth and decline.
One of many short, branched processes of a neuron that help send the nerve impulses toward the cell body.
The process by which bacteria use nitrates and release N2 as a product.
When a certain density of cells is reached, cell growth will slow or stop. This is because there are not enough raw materials for the growth and survival of more cells.
density-dependent limiting factors
Factors related to population size that come into play as population size approaches or passes the carrying capacity. Examples of density-dependent limiting factors include food, waste, and disease.
density-independent limiting factors
Factors that limit population growth that have nothing to do with the population size, such as natural disasters and weather.
The electric potential becomes less negative inside the cell, allowing an action potential to occur.
The driest land biome on earth, which experiences a wide range of temperatures from day to night and exists on nearly every continent.
Also know as decomposer. A consumer that obtains its energy through the consumption of dead animals and plants.
(Dicotyledon) An angiosperm plant that has two cotyledons.
The movement of molecules down their concentration gradients without the use of energy. It is a passive process during which molecules move from a region of higher concentration to a region of lower concentration.
The crossing of two different characters (BbRr x Bb Rr). A dihybrid cross between heterozygous gametes gives a 9 : 3 : 3 : 1 phenotype ration in the offspring.
An organism that has two copies of each type of chromosome. In humans, this refers to the pairs of homologous chromosomes.
A phylum that is associated with the archezoan eukaryotes.
Occurs when members of a population at one end of a spectrum are selected against and/or those at the other end are selected for.
A sugar consisting of two monosaccharides bound together. Common disaccharides include sucrose, maltose, and lactose.
dispersive DNA replication
A theory othat suggests that every daughter strandcontains some parental DNA, but it is dispersed among pieces of DNA not of parental origin.
Selection is disruptive when individuals at the two extremes of a spectrum of variation do better than the more common forms in the middle.
Describes the way populations are dispersed over a geographic area.
Two related species evolve in a way that makes them less similar, sometimes causing speciation.
The classification category that replaces the phylum in plant classification.
The addition of CH3 groups to the bases of DNA, rendering DNA inactive.
The main enzyme in DNA replication that attaches to primer proteins and adds nucleotides to the growing DNA chain in a 5'-to-3' direction.
The process by which DNA is copied. This process occurs during the S phase of the cell cycle to ensure that every cell prodeced during mitosis or meiosis receives the proper amount of DNA.
A ranking of pwer amoug the members of a group of individuals.
The shape of DNA--two strands help together by hydrogen bonds.
A classic aneuploid syndrome affecting one of every 700 children born in the United States. It most ofteninvolves a trisomy of chromosome 21, and leads to mental retardation, heart defects, short stature, and characteristic facial features.
Duchenne muscular dystrophy
Sex-linked disorder caused by the absence of an essential muscle protein that leads to progressive weakening of the muscles combined with a loss of muscle coordination.
All the individuals of a community and the environment in which it exists.
Outer germ layer that gives rise to the nervous system, skin, hair, and nails.
Animal whose basic metabolic rates increase in response to increase in temperature.
The presence of trisomy 18, which occurs in one out of every 10,000 live births and affects almost every organ of the body.
electron transport chain (ETC)
The chain of molecules, located in the mitochondria, that passes electrons along during the process of chemiosmosis to regenerate NAD+ to form ATP. Each time an electron passes to another member of the chain, the energy of the system drops.
The simplest form of matter.
The study of embryonic development.
Rate at which individuals relocate out of a given population.
A reaction that requires input of energy to occur. A + B + energy => C.
Process by which substances are brought into cells by enclosure into a membrane-created visticle that surrounds the substance and escorts it into the cell.
Inner germ layer that gives rise to the inner lining of the gut, digestive system, liver, thyroid, lungs, and bladder.
Cells that line the innermost layer of the cortex in plants that give rise to the casparian strip.
Inner wall of the uterus to which the embryo attaches.
Enzymes that initiate the digestion of proteins by hydrolyzind all the polypeptides into small amino acid groups.
Proposes that groups of prokaryotes associated in simbiotic relationships to form eukaryotes (mitochondria and chloroplasts).
Animal whose body temperature is relatively unaffected by external temperature
DNA region, also known as a "regulator," that is located thousands of bases away from the promoter that influences transcription by inter acting with specific transcription factors.
Catalytic proteins that re picky, interacting only with particular substrates. However, the enzymes can be reused and react with more than one copy of their substrate of choice and have a major effect on a reaction.
Develops into three germ layers of the enbryo: the endoderm, the mesoderm, and the ectoderm.
The protective outer coating of plants.
The coiled region that extends from the testes. This is where the sperm completes its maturation and waits until it is called on to do its duty.
Plasmids that can be incorporated into a bacterial chromosome.
A gene at one locus alters the phenotypic expression of a gene at another locus. A dihybrid cross involving epistatic genes produces a 9:4:3 phenotype ratio.
Valvelike trapdoor between the esophagus and the stomach.
Structure that connects the throat to the stomach.
Hormone make (secreted) in ovaries that stimulates development of sex characteristics in women and indces the release of luteinizing hormone (LH) before LH surge.
The study of animal behavior.
Plant hormone that initiates the ripening of fruit and the dropping of leaves and flowers from trees.
One of two major prokaryotic evolutionary branches. Categorized according to their mode of nutritional acquisition, mechanism of movement, shape, and other characteristics.
Complex cell that contains a nucleus, which functions as the control center of the cell, directing DNA replication, transcription, and cell growth. Organisms can be unicellular or multicellular and contain many different membrane-bound organelles.
Process by which a liquid changes into a vapor form. Functions in thermoregulation for humans when water elaves our bodies in the form of water vapor--sweat.
Descent with modification. Evolution happens to populations, not individuals, and describes change in allele frequencies in populations with time.
Repain mechanism for DNA replication in which a section of DNA containing an error is cut out and the gap is filled by DNA polymerase.
A reaction that gives off energy as a product. A + B => energy + C.
Process by which substances are exported out of the cell. A vesticule escorts the substance to the plasma membrane, fuses with the membrane and ejects its contents out of the cell.
Coding regions produced during transcription that re glued back together to produce the mRNA that is translated into a protein.
Enzymes that complete the digestion of proteins by hydrolyzing all the amino acids of the fragments remaining.
A population grows at a rate that creates a J-shaped curve.
Archaebacteria that live in environments with high salt concentrations.
The first generation of offspring, or the first "filial" generation in a genetic cross.
The second generation of offspring, or the second "filial" generation in a genetic cross.
The diffusion of particles across a selectively permeable membrane with the assistance of transport proteins that are specific in what they will carry and have a binding site designed for molecules of interest. This process requires no energy.
Organisms that can survive in oxygen-rich or oxygen-free environments.
Libids, made by combining glycerol and fatty acids, used as long-term energy stores in cells. They can be saturated or unsaturated.
Long carbon chain that contains a carboxyl group on one end that combines with glycerol molecules to form lipids.
Anaerobic respiration pathway that occurs in absense of oxygen. Produces less ATP than aerobic respiration.
Modecule that donates the electrons to NADP+ to produce NADPH during light reactions of photosynthesis.
fibrous root system
Root system found in monocots that provides the plant with a very strong anchor without going very deep into the soil.
Capillaries allow small particles through the pores of their endothelial linings, but large molecules such as proteins, platelets, and blood cells tend to remain in the vessel.
An innate behavior that seems to be a programmed response to some stimulus.
Hormone thought to assist in the blooming of flowers.
fluid mosaic model
Model that states that the membrane is made of a pospholipid bilayer with proteins of various lengths and sizes, interspersed with cholesterol.
Parasitic flatworm that alternates between sexual and asexual reproductive cycles.
follicle-stimulating hormone (FSH)
A gonadotropin that stimulates activities of the testes and ovaries. In females, it induces the development of the ovarian follicle, leading to the production and secretion of estrogen.
A hierarchical list of who snacks on who. For example, bugs are eaten by spiders, who are eaten by birds, who are eaten by cats.
Can be regarded as overlapping food chains that show all the various dietary relationships in an environment.
The behavior of actively searching and eating a particular food resource.
The physical manifestation of species that have gone extince (e.g., bones and imprints).
Plasmid that contains the genes necessary for the prodection of a sex pillus.
Delection or addition of DNA nucleotides that does not add or remove a multiple of three nucleotides. Usually produces a non-functional protein unless it occurs late in protein production.
Alleles are selected for or against depending on their relative frequency in a population.
The groups responsible for the chemical properties of organic compounds.
The first growth phase of the cell cycle that produces all the necessary raw materials for DNA synthesis.
Second growth phase of the cycle that produces all the necessary raw materials for mitosis.
Protective covering that provides a safe haven for the fertilization of the gametes and the development of the zygote in bryophytes, ferns, and some gymnosperms.
Sex cells produced during meiosis in the human life cycle.
A haploid multicellular organism.
Cells separate into three primary layers called germ layers, which eventually give rise to the different tissues of an adult.
The change in frequencies of alleles as genes from one population are incorporated into another.
Transduction caused by the accidental placement of host DNA into a phage instead of viral DNA during viral reproduction. The host DNA may find its way into another cell where crossover could occur.
Time needed for individuals to reach reproductive maturity.
Code that translated codons found on mRNA strands into amino acids.
A change in allele frequencies that is due to chance events.
An organism's genetic makeup for a given trait. A simple example of this could involve eye color, where B represents the allele for brown and b represents the allele for blue. The possible genotypes include homozygous brown (BB), heterozygous brown (Bb), and homozygous blue (bb).
Taxonomic group to which a species belongs.
Plant hormone that assists in stem elongation and induces growth in dormant seeds, buds, and flowers.
The early portion of the nephron where the filtration process begins.
Hormone that stimulates conversion of glycogen into glucose.
Three-carbon molecule that combines with fatty acids to produce a variety of lipids.
Occurs in the cytoslasm of cells and is the beginning pathway for both aerobic and anaerobic resporation. During glycolysis, a glucose molecule is broken down through a series of reactions into two molecules of ATP, NADH, and pyruvate.
Protein that has been modified by the addition of a sugar.
Organelle that modifies proteins, lipids, and other macromolecules by the addition of sugars and other molecules to form glycoproteins. The products are then sent to other parts of the cell.
Proteins vital to signal cascade pathways. Directly activate molecules such as adenyl cyclase to assist in a reaction.
The theory that evolutionary change is a steady, slow process.
Flattened channels and disks arranged in stacks found in the thylakoid membrane.
A plant's growth response to gravitational force. Auxin and gibberellins are involved in this response.
The difference over time between the dissolved oxygen concentrations of the light and dark bottles calculated in primary productivity experiments.
Assist in the growth of structures.
Cells within the epidermis of plants that control the opening and closing of the stomata.
First major seed plant to evolve. Heterosporous plant that usually transports its sperm through the use of pollen. Conifers are the major gymnosperm to know.
Loss of responsiveness to unimportant stimuli that do not provide appropriate feedback.