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264 Cards in this Set

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acid
A compound that increases hydrogen ion (H+) concentration in solution
acrosome
A cuplike body at the anterior tip of sperm containing several enzymes that aid the sperm in penetrating an egg
actin
A protein that makes up the thin filament in muscle. Actin and myosin, a larger protein, are the ultimate structural units of contractility.
agglutination
The clumping of cells or particles in a fluid. For example, agglutination of blood cells occurs when incompatible blood types are mixed.
aldosterone
An adrenal cortical hormone, which stimulates the reabsorption of sodium by the kidneys, and thereby reduces the amount of sodium in the urine
allele
One form of a gene, responsible for one of two or more contrasting traits
all-or-none principle
The concept that an event happens to its fullest possibility or not at all; usually used to refer to the firing or lack of firing of a nerve impulse
alveolus
A tiny thin-walled air sac in a lung, surrounded by a network of blood vessels, where gas exchange occurs between oxygen and carbon dioxide
amnion
One of the special extraembryonic membranes of reptiles, birds, and mammals; a fluid-filled sac in which the embryo floats
anaphase
A stage in mitosis or meiosis in which the chromosomes move from the equator toward the poles of the spindle
anemia
A condition resulting from decreased concentration of erythrocytes in the blood or from decreased concentration of hemoglobin in erythrocytes
angiosperm
A flowering plant whose ovules are enclosed within ovaries
anther
The pollen-producing organ of a flower
antheridium
An ovoid, multicellular male sex organ that produces sperm; found in mosses and ferns
anthropomorphism
The practice of regarding animals in terms of human characteristics
antibody
A specific protein synthesized in direct response to the presence of a foreign material (antigen) within the body
anticodon
The sequence of three nucleotides on transfer RNA that recognizes and pairs complementarity with three nucleotide codons of messenger RNA
antidiuretic hormone (ADH)
A hormone, produced by the hypothalamus, inhibits the excretion of urine by promoting water reabsorption in the kidneys
antigen
A foreign material that elicits an immune response resulting in the synthesis of an antibody
archegonium
A multicellular female sex organ that produces eggs; found in mosses, ferns, and conifers
artery
A thick-walled, elastic vessel that carries blood away from the heart
atrium
A chamber of the heart, which receives blood from a vein and pumps it to the next chamber, the ventricle
autonomic nervous system
A portion of the vertebrate nervous system that controls such involuntary activities as breathing and glandular secretion
autotroph
An organism capable of synthesizing its food from inorganic sources
auxin
A hormone involved in the regulation of plant growth
axon
A part of a neuron, a long process extending from the cell body and It usually carries impulses away from the cell body.
base
A compound that increases hydroxyl ion (OH ) in solution
biomass
The total weight of organisms in an ecosystem
biome
A major division of the Earth's surface, largely determined by climate but characterized by the plants and animals inhabiting it
blastula
A hollow ball resulting from cellular cleavages early in embryonic development
Bohr effect
High carbon dioxide level in the blood causes more oxygen to be released from hemoglobin
bronchus
One of the two posterior branches of the trachea serving as a passage for air to the lungs
buffer
A compound with dissociated ions that resists change in pH
Calvin cycle
The process by which carbon dioxide is reduced to carbohydrates during photosynthesis
cancer
A malignant tumor characterized by abnormal, uncontrolled growth
capillary
A small, thin-walled blood vessel that serves as connecting vessels between arteries and veins and permits exchange of nutrients, oxygen, and carbon dioxide between the blood and tissues
carbohydrates
Organic molecules composed of carbon, hydrogen, and oxygen that serve as cellular energy sources: sugar, starch, cellulose
catalyst
A chemical that speeds up a chemical reaction without being changed during the reaction
cell membrane
The outermost cytoplasmic layer of the cell, consisting mainly of phospholipid and protein
central nervous system
The division of the nervous system consisting of the brain and spinal cord
centriole
A small paired organelle, found in the cytoplasm, involved in the organization of the mitotic and meiotic spindle apparatus during cell division
cerebrum
A part of the brain divided into two hemispheres, with each hemisphere divided further into lobes and Each lobe contains special functional areas, including areas for speech, vision, movement, learning, and memory.
cervix
The neck of the uterus, which opens into the vaginal canal
chemoreceptor
Sensory cell or organ capable of perceiving chemical stimuli, such as those of smell and taste
chitin
An insoluble, strong polymer that forms the tough outer skeleton of the arthropods
chloroplast
A plastid that contains chlorophyll; photosynthesis is initiated when light strikes a chloroplast
cholesterol
A lipid that is an essential part of the human diet. Besides acting as a usual source of energy and assisting tissue maintenance, it is also needed for the production of bile acids and sex hormones.
chorion
An extraembryonic membrane that forms an outer membrane around the embryo; in mammals, the chorion makes up most of the placenta
chromosome
The nucleo-protein structure that contains the hereditary units, the genes
cilia
Short, bristle-like locomotor organelles on the free surface of cells
circadian rhythm
Daily cycle of behavior
cleavage
The cell divisions, initiated after fertilization, that mark the beginning of embryonic development
clitoris
Small erectile body just anterior to the vaginal opening; it is homologous to the male penis
clone
A genetically uniform population of cells or organisms derived asexually from a single ancestor
coacervates
Prebiotic aggregates formed by organic compounds, which may eventually have led to the formation of biological cells
codon
A sequence of three nucleotides in messenger RNA that codes for a single amino acid
coelom
The body cavity of an animal, between the body wall and the internal organs
colon
Part of the large intestine that functions in the reabsorption of water from undigested material
compound
A substance composed of molecules consisting of different kinds of atoms; every molecule of one compound contains the same elements joined in the same proportions by weight
condensation
A reaction in which small, simple molecules are combined into larger, more complex ones, with the elimination of one or more molecules of water (see hydrolysis)
conditioning
A type of learning in which an animal is rewarded or punished according to its reaction to a given stimulus
cones
(1) Light-sensitive cells in the retina of the eye; used in color vision (2) Spore-bearing structures in nonfiowering plants, such as pine trees
conjugation
Sexual union of similar cells, as in some algae, protozoa, and bacteria
corpus luteum
A glandular structure in mammals formed from the remnants of an ovarian follicle that secretes the hormone progesterone
crossover
A process during prophase I of meiosis, whereby nonsister chromatids exchange parts; also the genetic results of such a change
cuticle
A layer of wax and cutin coating the external surface of epidermal cells in plants
cyclic-AMP
(Cyclic 3',5'-adenosine monophosphate) - A chemical substance that plays a major role in mediating cellular activity in animals, bacteria, slime molds, etc
dendrite
Short, threadlike process, extending out from the cell body of a neuron, dendrites carry impulses toward the cell body.
deoxyribonucleic acid (DNA)
A double-stranded helical molecule that is a constituent of chromosomes; contains genetic information coded in specific sequences of its nucleotides
diabetes mellitus
An inherited metabolic disease caused by insufficient production of insulin and Cells are unable to use glucose, which is excreted in the urine.
diaphragm
A muscular partition that separates the thoracic and abdominal cavities and assists in respiratory function
diastole
Period during the cardiac cycle where the atrioventricular valves open, filling the ventricles with blood
dicotyledons (dicots)
One of two major classes of angiosperms characterized by two embryonic seed leaves (cotyledons)
diffusion
Tendency of molecules to disperse throughout a medium moving from a region of higher concentration to a region of lower concentration
digestion
The enzymatic process by which the body breaks down the large, complex molecules of food into its molecular and chemical components so that these nutrient molecules can be assimilated by the cells
dihybrid cross
A cross between individuals differing in two inheritable traits, or in which only two such different traits are considered by an experimenter
Down's syndrome (Mongolism, Trisomy 21)
A genetic disorder in which an extra chromosome is present
ECG (electrocardiogram)
A record of the electrical activity of the heart
ecology
The study of organisms in relation to all the forces that act upon them
ecosystem
A space containing an interacting group of organisms, more or less self-contained, such as an enclosed field, a pond, or small island
ectoderm
The outer germ layer of an embryo, which gives rise to the skin, hair, fingernails, horns, hooves, brain with associated nervous tract, and eyes
EEG (electroencephalogram)
A record of the electrical activity of the brain
ejaculation
Forceful emission of seminal fluid from the penis during climax
electron transport system
Represents a series of respiratory pigments of the mitochondrion that function as a "bucket brigade" for the passage of electrons from reduced coenzymes (NADH, FADH2) to oxygen
elements
Substances composed of molecules whose atoms have the same atomic number (number of protons)
endergonic
Activities or reactions that require energy
endocrine gland
A ductless gland that secretes its product into the bloodstream without an emptying tube
endoderm
The inner germ layer of an animal embryo lining the archenteron and it gives rise to the lining of the digestive tract, liver, lungs, and pancrease.
endometrium
The nutritious inner layer of the uterine wall
endoplasmic reticulum
A labyrinthine complex of double membranes in the cytoplasm of a cell, acting as a system of internal channels through which various materials move
endoskeleton
Internal skeleton, which provides support and rigidity of form; typical of vertebrates
endothermic
Reactions that occur with absorption of heat or other energy; endergonic; the opposite of exothermic or exergonic
energy
The capacity or ability to do work
enzyme
A protein that catalyzes or speeds up a biochemical reaction without being changed during the reaction
epiglottis
A valve that presses down and prevents food from entering the trachea or larynx during swallowing
epinephrine (adrenaline)
A neurohormone, secreted by the adrenal medulla, that produces a "'fight or flight" condition, which permits the body to react quickly and strongly to emergencies
erythroblast
Cell in bone marrow which is nucleated until it develops into a red blood cell
erythrocyte
A red blood cell
estrogen
One of the female sex hormones, secreted by ovarian follicles, which stimulates the thickening of the smooth muscle and the glandular lining of the inner walls of the uterus It also promotes the development of secondary sex characteristics
eukaryote
An organism or cell with a membrane-bound nucleus; possesses mitochondria, plastids, ftagella, and other organelles
eutrophication
An overabundance of nutrients provided in the waters of a river or lake, stimulating overgrowth of phytoplankton or algae. This floral population soon reaches a density at which vital gases and nutrients are used up, and the overgrown "blooms" produce toxins and die as an unpleasant rotting mass.
evolution
Progressive change
exergonic
Pertaining to activities or reactions that release energy
exocrine gland
A gland, such as a salivary or sweat gland, which exudes its secretion by a distinct duct or opening; contrasted with endocrine glands
exoskeleton
External or outer skeleton that provides structural support and protection for arthropods
fertilization
The union of gametes resulting in a doubling of the chromosome number
fetus
The highly developed human embryo, from the third month of pregnancy until birth
flagellum
A long, whiplike locomotor organelle on the surface of a cell
gamete
A sexual reproductive cell; an egg or sperm
ganglion
A cluster of cell bodies of neurons located outside the central nervous system
gastrulation
The phase of embryonic development when there is infolding of the blastula to form the gastrula
gene
A specific segment of DNA that controls a specific cellular function either by coding for a polypeptide or by regulating the action of other genes; the foundation of inheritable traits
gene pool
The total genetic material of all individuals in an interbreeding population (species)
genetic code
The set of linear sequences of triplet nucleotide bases that represent specific amino acids
genome
One complete set of genes in an organism: a haploid organism has one genome, a diploid has two.
genotype
An individual's genetic makeup
gill
The respiratory organ of aquatic and some terrestrial organisms. Gills extract oxygen and release carbon dioxide Gills extract oxygen and release carbon.dioxide
glomerulus
A tight ball of capillaries that filter blood through their walls into the Bowman's capsule
glucagon
A hormone, secreted by alpha cells in the pancreatic islets of Langerhans; increases blood glucose concentration by stimulating the liver to convert glycogen to glucose
glucocorticoids
A group of hormones concerned with glucose-glycogen balance in blood
glycolysis
The initial anaerobic breakdown of glucose to an intermediate compound, occurring in the cytoplasm of a cell
Golgi body
Organelles that exist as stacks of vesicles whose major function is the storage, modification, and packing of materials produced for secretory export
gonad
An organ that produces gametes, either ovaries or testes
gymnosperm
Nonflowering seed plant
habitat
The local physical dwelling place of an organism, such as a bare rock, a moist, cold, evergreen forest, or a tropical estuary
Hardy-Weinberg principle
Mathematical formula used in calculating the approximate frequencies of different alleles in a population after measuring the frequency of phenotypes in a representative sample of the whole population
hemoglobin
Chief transport protein involved in carrying oxygen within the red blood cell
hemophilia
Also called bleeder's disease; uncontrolled bleeding in humans due to the lack of a necessary blood-clotting constituent; a genetic disease caused by recessive alleles at either of the two sex-linked loci
hepatic portal system
A system of vessels in which the venous blood coming from the intestines passes through the capillaries in the liver before moving on to the posterior vena cava
heterozygous
An individual who has a different pair of alleles for a genetic trait
hibernation
The dormant state of animals, with concomitantly lowered body metabolism
histology
The study of biological tissue
histone
A basic protein associated with DNA in chromosomes
homeostasis
The maintenance of a measure of physiological stability in spite of environmental changes
homologous
Pertaining to similar body parts in different species, arising from common construction and development, such as bird, wings and whale flippers
homozygous
An individual who has the same pair of alleles for a genetic trait
instinct
Fixed action or stereotyped behavior; a controversial and poorly defined term, which is not generally acceptable to students of behavior
insulin
A hormone, secreted by beta cells in the islets of Langerhans portion of the pancreas: facilitates glucose transport across cell membranes-- Insulin enhances the conversion of glucose to glycogen
intron
An interruption in DNA by stretches of nucleotide strands that do not code for any amino acids
karyotype
The size, shape, and appearance of a metaphase chromosome set of an individual or species
kidney
An organ unique to the vertebrates that is the chief excretory unit
Krebs cycle
The major aerobic pathway for oxidative degradation of the products of glycolysis-- Also known as the tricarboxylic acid (TCA) cycle
learning
In experimental psychology, the modification of behavior as a result of changes in individual experience
leukocyte
A white blood cell
ligament
Tough sheet of fibrous tissue connecting two or more separate bones or cartilages
lipids
A class of organic compounds that tend to be insoluble in water or other polar solvents but soluble in organic solvents such as toluene or ether
liver
The largest gland, which has many important functions, including among others the storage of foods, production of bile salts, conversion of stored glycogen to glucose, deamination of amino acids, and breakdown of hemoglobin
lymphocyte
Any of several white blood cells involved in immunity
lysogenic
The inactive state of a virus in a living bacterial cell
rysosome
A cytoplasmic organelle rich in hydrolytic enzymes
Malpighian tubules
The excretory system of insects and spiders
marasmus
A disease caused by insufficient quantity of food, as contrasted with inadequate quality--It results in general weakness and lack of muscle tone
mechanoreceptor
Sensory cell or organ capable of perceiving changing mechanical stimuli, such as those of touch or hearing
meiosis
A series of cell divisions resulting in the development of gametes
menopause
Permanent termination of the menstrual period in a woman
menstrual cycle
Refers to the series of events that periodically modifies the female reproductive tract of humans and advanced primates
mesoderm
The middle germ layer of an embryo, between the ectoderm and endoderm, giving rise to muscle, connective tissue, bone, circulatory system, lining of coelom, and urogenital system
microtubule
Elongated, hollow, cylindrical structures that facilitate the motility of flagella and cilia
mitochondrion
A self-replicating cytoplasmic organelle, called the "powerhouse of the cell; the site of Krebs
cycle activity and the cytochrome system
Its main work is the production of ATP for use in cellular respiration
mitosis
Cell division process of a somatic cell
monocotyledons (monocots)
One of two major classes of angiosperms characterized by one embryonic seed leaf (cotyledon)
motor unit
A group of skeletal muscle fibers activated by the same nerve fiber
mutagen
Agents that produce genetic mutations
mycorrhiza
Fungus inhabiting the roots of higher plants, feeding off the host, and aiding the host in the intake of minerals
myelin
A fatly protein material, wrapped around the axon of some nerve fibers, that aids in the conduction of electrical impulses
myofibril
A subdivision of a muscle fiber
myosin
A 100-angstrom-thick protein that makes up the thick filaments of the muscle
nephridium
Organ responsible for excretion in earthworms
nephrons
Functional units of the kidney which assist in the actual production of urine
nerve
A bundle of fibers enclosed in a connective tissue sheath through which stimuli are transmitted from the central nervous system to the peripheral nervous system or vice versa
nerve impulse
An electrochemical impulse passing along a nerve fiber
neuron
A nerve cell, the fundamental unit of the nervous system
niche
The physiological, behavioral, or nutritional specialty of an organism, permitting it to survive in a given habitat; determined by the physiological or behavioral actions of a given species
nucleotide
A molecule consisting of a phosphate group, a 5-carbon sugar called a deoxyribose, and a single nitrogenous base selected from a pool of two purines (adenine or guanine) and two pyrimidines (thymine or cytosine)
nucleus
Round or oval body lying near the center of the cell responsible for replication and metabolic processes
omnivore
An organism that can and does eat both plant and animal material
organelle
Specialized structure of a cell comparable to the organs of the body
osmosis
The simple movement of a solvent through a selectively permeable membrane
ovary
An egg-producing organ
oxidation
A chemical reaction in which electrons are removed from the substance being oxidized
paleontology
The study of fossils
parasite
An organism that obtains its nourishment from another organism, usually by remaining in contact with its host
parasympathetic nervous system
A part of the autonomic nervous system that helps to regulate body functions
parathyroid glands
Four tiny glands, embedded in the thyroid gland, that secrete parathormone (PTH), which is responsible for increasing the calcium level and decreasing the phosphate level in blood
peristalsis
Digestive process consisting of a sequence of contractions propelling the food along the digestive tract in a mouth-to-anus direction
pH scale
Defined as the negative logarithm of the hydrogen-ion concentration
phagocytosis
Surface engulfment of large structures such as bacteria by protozoans or white blood cells
phloem
Functions in the transport of carbohydrates, amino acids, oligopeptides, and some lipids through the vascular tissues of plants
photoperiodism
The ability of some organisms to respond metabolically to variations in day length
photosynthesis
Process by which high-energy, complex food molecules are produced from simpler components by green plants and other autotrophic organisms in the presence of light energy
phytochrome
A light-sensitive pigment involved in seed germination, flowering, morphogenesis, anthocyanin synthesis, etc
pinocytosis
Surface engulfment of small structures by a cell membrane
pituitary gland
The so-called "master gland", and endocrine gland that controls most of the other endocrine glands
placenta
In mammals, the tissues composed partly of uterine wall and partly of extraembryonic membranes, through which waste and nutrients pass for a developing embryo
progesterone
One of the female sex hormones, produced by the corpus luteum
prokaryote
A cell that has no membrane-delimited organelles
prostaglandin
One of a group of fatty-acid hormones whose effects include contraction of uterine muscle, inhibition of progesterone secretion by the corpus luteum, and lowering of blood pressure
prostate gland
A gland in male mammals that furnishes fluid for the transport of sperm
protein
Class of organic compounds consisting almost entirely of carbon, hydrogen, oxygen, and nitrogen
radula
A saw-like device in some mollusks that assists in the mechanical grinding and processing of food
red blood cells
One of the formed elements in the blood, responsible for the transport of oxygen and carbon dioxide
reflex arc
A group of two or three neurons regulating a fairly simple body movement without conscious participation of the brain
releaser
In animal behavior, a signal, such as an odor, sound, or movement that evokes a specific, unlearned response
repressor
The protein that can combine with and repress action of an associated operator gene
respiration
Process whereby organisms oxidize metabolites in the presence of oxygen to capture the energy contained within the bonds of the metabolites
Rh factor [rhesus factor]
A group of blood cell antigens, clinically important because they can cause destruction of blood cells in certain newborn infants afflicted with erythroblastosis
ribonucleic acid (RNA)
A single-stranded nucleic acid found in the nucleus and cytoplasm of cells that is similar to DNA with the following exceptions: the 5-carbon sugar is ribose instead of deoxyribose and the pool of pyrimidines for the nitrogenous base consists of cytosine and uracil instead of thymine
rod
A photoreceptor in the retina of the eye containing light-sensitive pigment (rhodopsin)
sarcomere
A single muscle unit extending from one Z line to the next
saturated fat
Fatty acid whose carbon chain holds the maximum number of H atoms (only single bonds among the carbon atoms)
scrotum
An external sac between the male thighs containing testes and parts of spermatic cords
segregation, law of
Mendel's first law that affirms the existence of a pair of particulate factors (genes) which control each trait and which must segregate (separate) at gamete formation and then come together randomly at fertilization
seminal vesicle
The portion of the male reproductive system that secretes nutritive fluids for sperm
sex-linkage
Genetic traits inherited differently between males and females
society
Organisms living together in organized groups
somatotropic hormone (STH)
A hormone, secreted by the anterior lobe of the pituitary gland, that regulates the growth of the skeleton
speciation
The development of new species
species
A group of individuals capable of producing fertile offspring
spinal cord
A part of the central nervous system that passes through the protective vertebrae, from which 31 pairs of spinal nerves branch to each side of the body
spore
A reproductive cell in plants; in general, any nonsexual reproductive cell
sporophyll
A spore-bearing leaf
steroid
A fat-soluble compound of four connected carbon rings, occuring in many hormones
sympathetic nervous system
A part of the autonomic nervous system that controls metabolic activities
synapse
The junction between the axon terminal of one neuron and the dendrite or cell body of the next neuron
taxonomy
Chronological and morphological classification of organisms
tendon
A fibrous band that connects a muscle to a bone
territory
In animal behavior, a specific area guarded against intrusion by other members of the same species
test cross
A cross between an experimental organism of unknown genotype and one with recessive phenotype to determine the genotype of the unknown
testes
Male gonads that produce sperm cells
testosterone
The primary androgenic hormone that affects the production of sperm, the development of sex organs, and the appearance of secondary sex characteristics
thermodynamics
Branch of science that deals with the transformation of energy in all of its forms
thermoreceptor
Sensory cell or organ that is sensitive to changing temperature
thyroid
A gland in the neck that secretes the hormones thyroxine, which controls the rate of metabolism and growth, and thvroealcitonin, which lowers the calcium level in the blood
thyroxine
A hormone secreted by the thyroid that regulates metabolic rate and growth
totipotency
The ability of a cell (or nucleus) to develop (or regulate the development) into any kind of differentiated cell: having complete genetic ability
trachea
Commonly known as the windpipe, a lube connecting the larynx and the bronchi through which inhaled air flows.
unsaturated fat
Fatly acid whose carbon chain contains double or triple bonds between any of the carbon atoms.
ureter
The duct or passageway for the transport of urine from the kidneys to the bladder
urethra
The tube originating from the bladder through which urine flows and is excreted from the body
uterus
The womb: the pear-shaped organ located just beyond the vagina, which houses, nourishes, and protects (he developing fetus within its muscular walls.
vacuole
A membrane-bound vesicle located in the cellular cytoplasm, containing mostly water with salts proteins, crystals, and pigments.
vagina
A muscle-lined tube that receives sperm from the penis during sexual intercourse and allows the fetus to pass down from the uterus during childbirth.
vitamins
Special organic substances necessary in liny amounts to sustain life
white blood cells [leukocytes]
One of the formed elements of the blood: they serve as scavengers and immunizing agents.
xylem
Serves as a continuous passageway for the transport of water and dissolved solutes through the vascular tissues of plants, primarily in an upward direction.
zygospore
A thick-walled spore developing from the sexual fusion cells in some algae and fungi
zygote
The cell formed by the union of a sperm and an egg
hydrolysis
The decomposition or separation of a molecule through the addition of water molecules
hydrophilic
Referring to organisms that live where water is abundant
hypertension
High blood pressure
hyperthyroidism
A condition caused by an oversecretion of TSH (thyroid-stimulating hormone) by the pituitary or by a thyroid tumor, also known as Graves' disease.
hyphae
A tangled mass of multibranched threads or filaments of a fungus
hypoglycemia
A condition of low blood sugar, caused by excessive secretions of insulin
hypothalamus
A portion of the brain, below the thalamus, that controls many physiological and endocrine activities
hypothyroidism
Underactivity of the thyroid gland and the resultant insufficiency of iodine usually causes a goiter, a swelling in the neck.
hypothyroidism (goiter)
A condition characterized by an enlarged thyroid caused by insufficient iodine in the diet
immunology
The science dealing with the process whereby organisms develop a chemical resistance, an antibody, to a foreign substance, its antigen, such as pollen, viruses, or bacteria
implantation
The sinking of the blastocyst into the endometrium of the mammalian uterus
imprinting
The rapid fixing of social preferences. For example, newly hatched goslings will form an attachment to the first creature they can follow as their mother
independent assortment, law of
A generalization of Mendel which states that when one pair of alleles segregates during sexual reproduction, its manner of segregation is not affected by the manner of segregation of a second pair of alleles
induction
The influence of one type of tissue on the developmental pattern of another type of tissue
insertion
In anatomy, the point of attachment of a muscle to the bone that moves
instinct
Fixed action or stereotyped behavior; a controversial and poorly defined term, which is not generally acceptable to students of behavior