Bio Words Unit 7

Front 1

tissues

Back 1

An aggregation of morphologically similar cells and associated intercellular matter acting together to perform one or more specific functions in the body. There are four basic types of tissue: muscle, nerve, epidermal, and connective.

Front 2

osteoblast

Back 2

A cell from which bone develops; a bone-forming cell.

Front 3

squamous

Back 3

covered with or formed of squamae or scales.

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mesenteries

Back 4

the membrane, consisting of a double layer of peritoneum, that invests the intestines, attaching them to the posterior wall of the abdomen, maintaining them in position in the abdominal cavity, and supplying them with blood vessels, nerves, and lymphatics, esp. the part of this membrane investing the jejunum and ileum.

Front 5

columnar

Back 5

shaped like a column

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macrophages

Back 6

Any of the large phagocytic cells of the reticuloendothelial system.

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homeostasis

Back 7

the tendency of a system, esp. the physiological system of higher animals, to maintain internal stability, owing to the coordinated response of its parts to any situation or stimulus tending to disturb its normal condition or function.

Front 8

fibroblasts

Back 8

A cell that gives rise to connective tissue.

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adipose tissue

Back 9

loose connective tissue in which fat cells accumulate.

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abdominal cavity

Back 10

the cavity containing the major viscera; in mammals it is separated from the thorax by the diaphragm

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pepsin

Back 11

an enzyme, produced in the stomach, that in the presence of hydrochloric acid splits proteins into proteoses and peptones.

Front 12

villi

Back 12

one of the long, soft, straight hairs covering the fruit, flowers, and other parts of certain plants

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lacteal

Back 13

any of the minute lymphatic vessels that convey chyle from the small intestine to the thoracic duct

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peristalsis

Back 14

the progressive wave of contraction and relaxation of a tubular muscular system, esp. the alimentary canal, by which the contents are forced through the system

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gastrin

Back 15

a hormone that stimulates the secretion of gastric juice.

Front 16

herbivores

Back 16

An animal that feeds chiefly on plants.

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bile

Back 17

bitter, alkaline, yellow or greenish liquid, secreted by the liver, that aids in absorption and digestion, esp. of fats.

Front 18

secretin

Back 18

a polypeptide hormone, produced in the small intestine, that activates the pancreas to secrete pancreatic juice.

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lipase

Back 19

any of a class of enzymes that break down fats, produced by the liver, pancreas, and other digestive organs or by certain plants.

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bolus

Back 20

a round mass of medicinal material, larger than an ordinary pill. Abbreviation: bol.

Front 21

diastole

Back 21

the normal rhythmical dilatation of the heart during which the chambers are filling with blood. Compare systole (def. 1).

Front 22

hemolymph

Back 22

a fluid in the body cavities and tissues of invertebrates, in arthropods functioning as blood and in some other invertebrates functioning as lymph

Front 23

fibrinogen

Back 23

a globulin occurring in blood and yielding fibrin in blood coagulation

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fibrin

Back 24

the insoluble protein end product of blood coagulation, formed from fibrinogen by the action of thrombin in the presence of calcium ions

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thrombus

Back 25

a fibrinous clot that forms in and obstructs a blood vessel, or that forms in one of the chambers of the heart

Front 26

trachea

Back 26

the tube in humans and other air-breathing vertebrates extending from the larynx to the bronchi, serving as the principal passage for conveying air to and from the lungs; the windpipe

Front 27

platelets

Back 27

A minute, nonnucleated, disklike cytoplasmic body found in the blood plasma of mammals that is derived from a megakaryocyte and functions to promote blood clotting. Also called blood platelet, thrombocyte.

Front 28

venules

Back 28

A small vein, especially one joining capillaries to larger veins

Front 29

alveoli

Back 29

an air cell of the lungs, formed by the terminal dilation of tiny air passageways

Front 30

myoglobin

Back 30

hemoglobin of muscle, weighing less and carrying more oxygen and less carbon monoxide than blood hemoglobin

Front 31

lysozyme

Back 31

an enzyme that is destructive of bacteria and functions as an antiseptic, found in tears, leukocytes, mucus, egg albumin, and certain plants

Front 32

cd8

Back 32

A glycoprotein on the surface of killer cells that enhances binding with MHC molecules.

Front 33

cd4

Back 33

a protein on the surface of T cells and other cells, functioning as a receptor for the AIDS virus antigen

Front 34

phagocytosis

Back 34

the ingestion of a smaller cell or cell fragment, a microorganism, or foreign particles by means of the local infolding of a cell's membrane and the protrusion of its cytoplasm around the fold until the material has been surrounded and engulfed by closure of the membrane and formation of a vacuole: characteristic of amebas and some types of white blood cells

Front 35

rh factor

Back 35

any of a type of specific antigen present on the surface of red blood cells, persons having inherited such antigens being designated Rh+ (Rh positive) and persons lacking them, a much smaller group, being designated Rh− (Rh negative): blood of Rh− persons is incompatible with Rh+ blood because of antibody reaction, and an Rh− woman who bears an Rh+ baby will have formed antibodies to the fetal blood that, unless removed from her bloodstream by apheresis in a subsequent pregnancy, will be carried across the placenta and destroy red blood cells of the next Rh+ fetus, resulting in erythroblastosis in the newborn.

Front 36

histamine

Back 36

a histidine-derived amine compound that is released mainly by damaged mast cells in allergic reactions, causing dilation and permeability of blood vessels and lowering blood pressure

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chemokines

Back 37

Any of various cytokines produced in acute and chronic inflammation that mobilize and activate white blood cells.

Front 38

perforin

Back 38

a protein produced by killer cells of the immune system that causes disintegration of targeted cells by forming pores in their membranes.

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pyrogens

Back 39

A substance that produces fever

Front 40

interferon

Back 40

any of various proteins, produced by virus-infected cells, that inhibit reproduction of the invading virus and induce resistance to further infection

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epitope

Back 41

a determining agent or factor.

Front 42

thermoregulation

Back 42

the regulation of body temperature

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osmoregulation

Back 43

the process by which cells and simple organisms maintain fluid and electrolyte balance with their surroundings

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torpor

Back 44

sluggish inactivity or inertia

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excretion

Back 45

the substance excreted, as urine or sweat, or certain plant products

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estivation

Back 46

the arrangement of the parts of a flower in the bud.

Front 47

hibernation

Back 47

to spend the winter in close quarters in a dormant condition, as bears and certain other animals. Compare

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ectotherm

Back 48

a cold-blooded animal.

Front 49

renin

Back 49

a proteolytic enzyme secreted by the kidneys that is involved in the release of angiotensin.

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filtration

Back 50

liquid that has been passed through a filter.

Front 51

euryhaline

Back 51

of an aquatic organism) tolerating a wide range of salinity

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hormone

Back 52

Also called phytohormone. any of various plant compounds, as auxin or gibberellin, that control growth and differentiation of plant tissue.

Front 53

endorphin

Back 53

any of a group of peptides occurring in the brain and other tissues of vertebrates, and resembling opiates, that react with the brain's opiate receptors to raise the pain threshold.

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melatonin

Back 54

a hormone secreted by the pineal gland in inverse proportion to the amount of light received by the retina, important in the regulation of biorhythms: in amphibians, it causes a lightening of the skin.

Front 55

epinephrine

Back 55

a hormone secreted by the adrenal medulla upon stimulation by the central nervous system in response to stress, as anger or fear, and acting to increase heart rate, blood pressure, cardiac output, and carbohydrate metabolism

Front 56

ecdysone

Back 56

an insect hormone that stimulates metamorphosis

Front 57

calcitonin

Back 57

a polypeptide hormone that participates in the regulation of calcium levels in vertebrates by inhibiting loss of calcium from bone to the blood.

Front 58

thyronxine

Back 58

the thyroid gland hormone that regulates the metabolic rate of the body.

Front 59

androgens

Back 59

any substance, as testosterone or androsterone, that promotes male characteristics.

Front 60

glucagon

Back 60

a hormone secreted by the pancreas that acts in opposition to insulin in the regulation of blood glucose levels

Front 61

progestin

Back 61

any substance having progesteronelike activity

Front 62

hymen

Back 62

a fold of mucous membrane partly closing the external orifice of the vagina in a virgin

Front 63

vestibule

Back 63

any of various cavities or hollows regarded as forming an approach or entrance to another cavity or space, as that of the internal ear.

Front 64

scrotum

Back 64

the pouch of skin that contains the testes.

Front 65

clitoris

Back 65

the erectile organ of the vulva, homologous to the penis of the male.

Front 66

fission

Back 66

the division of an organism into new organisms as a process of reproduction.

Front 67

urethra

Back 67

the membranous tube that extends from the urinary bladder to the exterior and that in the male conveys semen as well as urine.

Front 68

coitus

Back 68

sexual intercourse, esp. between a man and a woman

Front 69

acrosome

Back 69

an organelle covering the head of animal sperm and containing enzymes that digest the egg cell coating, thus permitting the sperm to enter the egg.

Front 70

gonads

Back 70

An organ in animals that produces gametes, especially a testis or ovary.

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oviduct

Back 71

either of a pair of tubes that transport the ova from the ovary to the exterior, the distal ends of which form the uterus and vagina in higher mammals

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morula

Back 72

the mass of cells resulting from the cleavage of the ovum before the formation of a blastula.

Front 73

blastocoel

Back 73

the cavity of a blastula, arising in the course of cleavage

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epigenesis

Back 74

the theory that an embryo develops from the successive differentiation of an originally undifferentiated structure (opposed to preformation).

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blastula

Back 75

the early developmental stage of an animal, following the morula stage and consisting of a single, spherical layer of cells enclosing a hollow, central cavity.

Front 76

gastrulation

Back 76

any process, as invagination, by which a blastula or other form of embryo is converted into a gastrula

Front 77

amniotes

Back 77

Any of a group of vertebrates that have an amnion during embryonic development, including reptiles, birds, and mammals.

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amnions

Back 78

the innermost of the embryonic or fetal membranes of reptiles, birds, and mammals; the sac in which the embryo is suspended

Front 79

allantois

Back 79

a vascular, extraembryonic membrane of birds, reptiles, and certain mammals that develops as a sac or diverticulum from the ventral wall of the hindgut

Front 80

chorion

Back 80

the outermost of the extraembryonic membranes of land vertebrates, contributing to the formation of the placenta in the placental mammals.

Front 81

allantois

Back 81

a vascular, extraembryonic membrane of birds, reptiles, and certain mammals that develops as a sac or diverticulum from the ventral wall of the hindgut.

Front 82

aspartate

Back 82

a salt or ester formed from aspartic acid.

Front 83

neuropeptides

Back 83

Any of various short-chain peptides found in brain tissue, such as endorphins

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pons

Back 84

any tissue connecting two parts of a body organ or structure

Front 85

ventricles

Back 85

The chamber on the left side of the heart that receives arterial blood from the left atrium and contracts to force it into the aorta.

Front 86

thalamus

Back 86

the middle part of the diencephalon through which sensory impulses pass to reach the cerebral cortex

Front 87

axons

Back 87

The usually long process of a nerve fiber that generally conducts impulses away from the body of the nerve cell.

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Front 88

glycine

Back 88

a colorless, crystalline, sweet, water-soluble solid, H2NCH2COOH, the simplest amino acid: used chiefly in organic synthesis and biochemical research. Abbreviation: Gly; Symbol: G

Front 89

serotonin

Back 89

a neurotransmitter, derived from tryptophan, that is involved in sleep, depression, memory, and other neurological processes.

Front 90

basal nuclei

Back 90

indicating a standard low level of activity of an organism, as during total rest

Front 91

oligodendrocytes

Back 91

One of the cells comprising the oligodendroglia

Front 92

myofibrils

Back 92

Any of the threadlike fibrils that make up the contractile part of a striated muscle fiber. Also called sarcostyle.

Front 93

sclera

Back 93

a dense, white, fibrous membrane that, with the cornea, forms the external covering of the eyeball

Front 94

choroid

Back 94

like the chorion; membranous

Front 95

cornea

Back 95

the transparent anterior part of the external coat of the eye covering the iris and the pupil and continuous with the sclera.

Front 96

malleus

Back 96

the outermost of a chain of three small bones in the middle ear of mammals. Also called hammer. Compare incus (def. 1), stapes.

Front 97

incus

Back 97

the middle one of a chain of three small bones in the middle ear of humans and other mammals. Compare malleus, stapes.

Front 98

iris

Back 98

any plant of the genus Iris, having showy flowers and sword-shaped leaves. Compare iris family.

Front 99

cochlea

Back 99

a spiral-shaped cavity forming a division of the internal ear in humans and in most other mammals.

Front 100

retina

Back 100

the innermost coat of the posterior part of the eyeball that receives the image produced by the lens, is continuous with the optic nerve, and consists of several layers, one of which contains the rods and cones that are sensitive to light.

Front 101

exteroreceptors

Back 101

a receptor responding to stimuli originating outside the body.