BIO - TERMS - FREQUENCY > 1 PT 6 Flashcards

Question

digestion

Answer 1

Enzymatic hydrolysis of major nutrients in the gastrointestinal system to yield their simpler components. // The irst stage of catabolism, in which food is broken down by hydrolysis of ester, gly coside (acetal), and peptide (amide) bonds to yield fatty acids, simple sugars, and amino acids.

Answer 2

The process of amplifying a specific sequence of DNA. // (1) The act of making many identical copies (typically billions) of a DNA molecule—the amplification of a particular DNA sequence. (2) Also, the isolation of a particular stretch of DNA (often a particular gene) from the rest of the cell’s genome.

Answer 3

A cell that gives DNA to a recipient cell during genetic recombination. // A bacterium that donates DNA to another (recipient) cell during recombination in bacteria (cf. Recipient cell).

Answer 4

A term used to describe a phenomenon that occurs in an abnormal place. // (ek-top′ik) Out of place; e.g., in an ectopic pregnancy, the pre-embryo implants in the uterine tube rather than in the uterus.

Answer 5

Microscope that uses a beam of electrons to create the image. // A microscope that uses electrons instead of light to produce an image.

Answer 6

An enzyme that breaks strands of DNA at internal positions; some are involved in recombination of DNA. // Enzymes that hydrolyze the interior phosphodiester bonds of a nucleic acid—that is, act at bonds other than the terminal bonds.

Answer 7

A disease acquired by many hosts in a given area in a short time. // A pattern of disease characterized by rapid and sudden appearance of cases spreading over a wide area. (Chapter 1)

Answer 8

Protein that helps load initiator tRNA on to the ribosome, thus initiating translation. // A combination of proteins needed to initiate translation and protein synthesis on the ribosomes.

Answer 9

A general sense of tiredness that is often accompanied by a decrease in muscular performance. // Reduction in athletic performance that stems from physiologic events in muscle (peripheral fatigue) or the central nervous system (central fatigue).

Answer 10

Reaction whose velocity is proportional to the concentration of a substrate. // Designates a reaction whose rate-limiting step is unimolecular and whose kinetics therefore depend on the concentration of only one reactant.

Answer 11

Type of effector CD4 T cell that resides in lymphoid follicles and provides help to B cells for antibody production. // Type of T cell located in lymphoid follicles that secretes various cytokines to stimulate B cells to undergo antibody class switching and somatic hypermutation.

Answer 12

A tumorous growth in plants. // Issue deformations found in plants infected by certain microorganisms or colonized by insects.

Answer 13

Process by which DNA sequence information can be transferred from one DNA helix (which remains unchanged) to another DNA helix whose sequence is altered. It often accompanies general recombination events. // A process, often associated with recombination, during which one allele is replicated at the expense of another, leading to non-Mendelian segregation ratios. In whole tetrads, for example, the ratio may be 6:2 or 5:3 instead of the expected 4:4.

Answer 14

A steroid hormone that regulates gene expression in higher animals. // (glū-kō-kōr′tikōyd) Group of hormones released from the adrenal cortex; help regulate glucose levels; e.g., cortisol, corticosteroid.

Answer 15

Unicellular glands that secrete mucin. // Specialized epithelial cells located in many sites throughout the body responsible for mucus production; important in protection of the epithelium.

Answer 16

Proteases that induce apoptosis. // Members of a family of serine proteases that are released from activated cytotoxic T cells and induce apoptosis of target cells. (Chapter 4)

Answer 17

A hemoglobin-binding protein in serum. // A serum protein, alpha globulin, in the blood.

Answer 18

A liver enzyme that cleaves the fatty acids of a triglyceride; it is involved in the production of lowdensity lipoproteins. // An extracellular enzyme in the liver that hydrolyzes triglycerides and phospholipids in remnant particles and high-density lipoprotein (HDL).

Answer 19

Genes that have evolved from a common ancestral gene (cf. Orthologous genes; Paralogous genes).

Answer 20

Substance that dissolves in water.

Answer 21

The most variable parts of the variable domains in the immunoglobulins; sites of contact with the antigen. // In immunology: any of the three small parts of the variable region of an immunoglobulin or T cell receptor chain that show the highest variability from molecule to molecule and contribute to the antigen-binding site.

Answer 22

Having the property of being recognized most effi ciently by cytotoxic T lymphocytes and antibodies; said of peptides and epitopes. (Chapter 5) // Describes epitopes in an antigen that are preferentially recognized by T cells, such that T cells specific for those epitopes come to dominate the immune response.

Answer 23

The fraction of the population that contracts a disease during a particular period of time. // Th e frequency with which a disease appears in a particular population or area (e.g., the number of newly diagnosed cases during a specifi c period); distinct from the prevalence (i.e., the number of cases in a population on a certain date). (Chapter 1)

Answer 24

A drug or toxin that blocks the normal action of a protein or a biochemical process. // Any substance or object that retards a chemical reaction; a major or modifier gene that interferes with a reaction.

Answer 25

An anabolic hormone that facilitates the uptake of glucose and can stimulate protein synthesis. // A hormone released by the cells of the pancreas; regulates blood glucose levels by controlling the expression of glucose transporters in the plasma membrane of non-neuronal cells.

Answer 26

Different forms of the same protein, for example the different forms encoded by different alleles of the same gene. // A member of a family of closely related proteins—proteins that have some amino acid sequences in common and some different.

Answer 27

A condition in which the concentration of ketone bodies in the blood, tissues, and urine is abnormally high. // A physiologic state in which ketone body production exceeds metabolism, resulting in an accumulation of ketone bodies in the blood and tissue.

Answer 28

A law regarding the relationship between the balanced chemical equation and the expression of the equilibrium constant. // The law stating that the rate of any given chemical reaction is proportional to the product of the activities (or concentrations) of the reactants.

Answer 29

An atom, ion, or molecule that is an electron pair acceptor. // A substance with a vacant low-energy orbital that can accept an electron pair from a base. All electrophiles are Lewis acids.

Answer 30

Artificial phospholipid bilayer vesicle formed from an aqueous suspension of phospholipid molecules. // A small, spherical vesicle composed of a phospholipid bilayer, forming spontaneously when phospholipids are suspended in an aqueous buffer.

Answer 31

A state in which phage DNA is incorporated into the host cell without lysis. // The phenomenon by which the lysogenic state is established and maintained in bacteria. (Chapter 1)

Answer 32

Amount of energy used in a given time period. // The energy expended in a certain period of time (such as kilocalories per hour).

Answer 33

Cluster of genes in one vertebrate chromosome (chromosome 6 in humans) that code for a set of highly polymorphic cell-surface glycoproteins (MHC proteins). // Hypothetical complexes containing one antigen peptide:MHC molecule and one self peptide:MHC molecule on the surface of the antigen-presenting cell, which have been proposed to initiate T-cell activation.

Answer 34

A species that has been studied intensively over a long period and thus serves as a “model” for deriving fundamental biological principles. // Plants, animals, and microbes that are routinely used in genetic analysis.

Answer 35

The ability of an organism to move by itself. // Cell movement, usually accomplished through the action of specialized structures such as cilia and flagella.

Answer 36

A mass of long filaments of cells that branch and intertwine, typically found in molds. // Threadlike filament making up the vegetative portion of thallus fungi.

Answer 37

A mathematical relationship used to calculate an ionic equilibrium potential. // Equation that computes relates the electrical potential (voltage) generated by differences in ion concentrations across a membrane.

Answer 38

An antigen–antibody reaction that inactivates a bacterial exotoxin or virus. // Inhibition of the infectivity of a virus or the toxicity of a toxin molecule by the binding of antibodies.

Answer 39

Event occurring occasionally during meiosis in which a pair of homologous chromosomes fails to separate so that the resulting germ cell has either too many or too few chromosomes. // Failure of disjunction or separation of homologous chromosomes in mitosis or meiosis, resulting in too many chromosomes in some daughter cells and too few in others. Examples: In meiosis, both members of a pair of chromosomes go to one pole so that the other pole does not receive either of them; in mitosis, both sister chromatids go to the same pole.

Answer 40

The region in a bacterial cell containing the chromosome. // In bacteria, the nuclear zone that contains the chromosome but has no surrounding membrane.

Answer 41

A microorganism that does not ordinarily cause a disease but can become pathogenic under certain circumstances. // Microbes of the normal flora that can cause disease only if the immune systems are weakened or if they gain access to a normally sterile part of the body.

Answer 42

A secondary immune response to an antigen that is related, but not identical to, the antigen that elicited the primary response. (Chapter 5) // The tendency of humans to make antibody responses to those epitopes shared between the first strain of a virus they encounter and subsequent related viruses, while ignoring other highly immunogenic epitopes on the second and subsequent viruses.

Answer 43

A worldwide epidemic. (Chapter 1) // An epidemic that occurs worldwide.

Answer 44

The injection of antibody or immune serum into a naive recipient to provide specific immunological protection. Cf. active immunization. // Direct administration of the products of the immune response (e.g., antibodies or stimulated immune cells) obtained from an appropriate donor(s) to a patient; contrasts with active immunization. (Chapter 8)

Answer 45

Lymphoid organ in which T cells and B cells interact and respond to foreign antigens. Examples are spleen, lymph nodes, and mucosalassociated lymphoid organs. // The lymph nodes, spleen, and mucosa-associated lymphoid tissues, in which adaptive immune responses are induced, as opposed to the central lymphoid organs, in which lymphocytes develop. They are also called secondary lymphoid organs and tissues.

Answer 46

Tumor promoters from croton oil; stimulate protein kinase C. // Diterpene from Euphorbiaceae and Thymelaeaceae resembling diacylglycerol in structure and therefore activates protein kinase C.

Answer 47

In photosynthetic cells, a functional set of light-absorbing pigments and its reaction center, where the energy of an absorbed photon is transduced into a separation of electric charges. // Multiprotein complex involved in photosynthesis that captures the energy of sunlight and converts it to useful forms of energy: a reaction center plus an antenna.

Answer 48

A clearing in a bacterial lawn resulting from lysis by phages. See also dental plaque. // A circular zone of infected cells that can be distinguished from the surrounding monolayer. (Chapter 2)

Answer 49

A heterogeneous pool of antibodies produced in an animal by different B lymphocytes in response to an antigen. Different antibodies in the pool recognize different parts of the antigen. // The antibody repertoire against the many epitopes of an antigen produced in an animal. (Chapter 2)

Answer 50

Channel-forming proteins of the outer membranes of bacteria, mitochondria, and chloroplasts. // A type of protein in the outer membrane of gram-negative cell walls that permits the passage of small molecules.

Answer 51

The immediate RNA product of transcription before any posttranscriptional processing reactions. // The RNA molecule produced by transcription prior to any posttranscriptional modifications; also called a premRNA in eukaryotes.

Answer 52

A gram-positive bacterium or plant cell treated to remove the cell wall. // A plant or bacterial cell from which the wall has been removed.

Answer 53

An atom or group of atoms possessing an unpaired electron; also called a free radical. // A species that has an odd number of electrons, such as the chlorine radical, Cl·.

Answer 54

Any enzymatic process by which the linear arrangement of nucleic acid sequences in a chromosome is altered by cleavage and rejoining. // The production of gene combinations not found in the parents by the assortment of nonhomologous chromosomes and crossing over between homologous chromosomes during meiosis. For linked genes, the frequency of recombination can be used to estimate the genetic map distance; however, high frequencies (approaching 50 percent) do not yield accurate estimates.

Answer 55

A type of T cell that suppresses the development, activation, or function of other immune cells via secreted cytokines or cell-surface inhibitory proteins. // Effector CD4 T cells that inhibit T-cell responses and are involved in controlling immune reactions and preventing autoimmunity. Several different subsets have been distinguished, notably the natural regulatory T-cell lineage that is produced in the thymus, and the induced regulatory T cells that differentiate from naive CD4 T cells in the periphery in certain cytokine environments.

Answer 56

The ability to ward off diseases through innate and adaptive immunity. // A general immune strategy aimed at reducing or eliminating pathogens; compare with avoidance and tolerance.

Answer 57

Any of the integrated retroviruses or the transposable elements that resemble them. // A nucleic acid sequence that has been copied into DNA from an intermediate by reverse transcription. (Chapter 7)

Answer 58

An inverted, U-shaped tube containing a strong electrolyte (such as KNO3) that connects two half-cells, allowing a flow of ions that neutralizes charge buildup. // An ionic attraction between two oppositely charged groups in a protein chain.

Answer 59

Glial cell responsible for forming myelin sheaths in the peripheral nervous system. Compare oligodendrocyte. // A glial cell that provides myelin in the peripheral nervous system.

Answer 60

Genes expressed by subsets of cells in the embryo that refine the pattern of gene expression so as to define the boundaries and ground plan of the individual body segments. // A group of genes that control the early development of Drosophila embryos. Their products define segments along the anterior–posterior axis.

Answer 61

A sex-related difference in structure or behavior. // The distinctly different appearance of adult male and female organisms.

Answer 62

A DNA sequence that helps to reduce or shut off the expression of a nearby gene. // DNA sequences that reduce the rate of transcription by binding regulatory proteins.

Answer 63

In bacteria, a coordinated induction of a variety of genes in response to high levels of DNA damage. // The synthesis of a whole set of DNA repair, recombination, and replication proteins in bacteria containing severely damaged DNA (for example, following exposure to UV light).

Answer 64

An amphipathic lipid with a sphingosine backbone to which are attached a long-chain fatty acid and a polar alcohol. // A class of membrane lipid containing sphingosine (2-amino- 4-octadecene-1,3-diole), an amino alcohol with unsaturated 18-hydrocarbon chain.

Answer 65

A nonequilibrium state of a system through which matter is flowing and in which all components remain at a constant concentration. // A state in which the rate of synthesis equals the rate of degradation.

Answer 66

A mutation caused by the replacement of one base by another. substrate The specific compound acted upon by an enzyme. // Replacement of one or more nucleotides in a nucleic acid. (Chapter 3)

Answer 67

A specific group of signs or symptoms that accompany a disease. // A group of symptoms that occur together and represent a particular disease.

Answer 68

An enzyme that catalyzes the addition of nucleotide residues of a single kind to the 3’ end of DNA chains. // An enzyme that adds nucleotides to the 3′ termini of DNA molecules.

Answer 69

A subset of effector CD4 T cells characterized by the cytokines they produce. They are mainly involved in activating macrophages but can also help stimulate B cells to produce antibody.

Answer 70

Any of a class of molecules derived from arachidonate and involved in platelet aggregation during blood clotting. // A prostaglandin-related product made by platelets.

Answer 71

A chemical element required by an organism in only trace amounts. // A chemical element required in small amounts for growth.

Answer 72

Mice in which extra genes have been introduced by genetic engineering. // Mouse with an artificially inserted gene.

Answer 73

A helical structure of three polypeptides that is the basic unit of all collagens. // The collagen molecule.

Answer 74

A term that describes a reaction involving only one particle that goes on to form products. // A reaction that occurs by spontaneous transformation of the starting material without the intervention of other reactants. For example, the dissociation of a tertiary alkyl halide in the SN1 reaction is a uni molecular process.

Answer 75

An intracellular inclusion, in eukaryotic cells, surrounded by a plasma membrane; in prokaryotic cells, surrounded by a proteinaceous membrane. // Large fluid-filled compartment found in most plant and fungal cells, typically occupying more than a third of the cell volume.

Answer 76

(vis-kos′i-tē) Thickness of a solution; provides resistance to fluid flow. // A measure of the resistance of a liquid to flow.

Answer 77

The protein defective in patients with Wiskott–Aldrich syndrome. When activated, WASp promotes actin polymerization. // Key target of activated Cdc42. Exists in an inactive folded conformation and an activated open conformation; association with Cdc42 stabilizes the open form, enabling binding to the Arp 2/3 complex and enhancing actinnucleating activity.

Answer 78

A disease of the eye caused by vitamin A deficiency. It is characterized by a dry and thickened conjunctiva and ulceration of the cornea that leads to blindness. // Dry eyes, in vitamin A deficiency.

BIO - TERMS - FREQUENCY > 1 PT 6 Flashcards

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