BIO - TERMS - GENE Flashcards
Abortive infection
An incomplete infectious cycle; virions infect a susceptible cell or host but do not complete reproduction, usually because an essential viral or cellular gene is not expressed. (Chapter 5)
absolute strength
The amount of force that can be generated regardless of body size.
Additive genetic variance
The portion of the total phenotypic variance in a quantitative trait that is due to the additive effects of alleles.
Aerobic metabolism
Cell energy metabolism where electrons finally are transferred to molecular oxygen. This type of energy metabolism generates ATP with high efficiency.
alcoholic liver disease
A general term that is used to describe alcohol-related liver diseases, such as fatty liver, hepatitis, fibrosis, and cirrhosis.
Allele-specific oligonucleotide probes
Probes that can distinguish between different alleles (variants) of a gene.
Allelic heterogeneity
Different disease-causing mutations in the same gene.
allogeneic
Describes two individuals or two mouse strains that differ at genes in the MHC. The term can also be used for allelic differences at other loci.
Allopolyploid
A polyploid having chromosome sets from different species; a polyploid containing genetically different chromosome sets derived from two or more species.
Allotetraploid
An organism with four genomes derived from hybridization of different species. Usually, in forms that become established, two of the four genomes are from one species and two are from another species.
Alport syndrome
Genetic disorder of type IV collagen leading to kidney failure.
Amniotic fl uid
Liquid contents of the amniotic sac of higher vertebrates containing cells of the embryo (not of the mother). Both fl uid and cells are used for diagnosis of genetic abnormalities of the embryo or fetus.
Amorphic
A term applied to a mutant allele that completely abolishes gene expression. Such a mutant allele is called an amorph.
AMP-activated protein kinase (AMPK)
A protein kinase activated by 5’-adenosine monophosphate (AMP). AMPK action generally shifts metabolism away from biosynthesis toward energy production.
Anchor gene
A gene that has been positioned on both the physical map and the genetic map of a chromosome.
Antennapedia complex
One of two gene clusters in Drosophila that contain Hox genes; genes in the Antennapedia complex control the differences among the thoracic and head segments of the body.
atopy
A genetically based increased tendency to produce IgE-mediated allergic reactions against innocuous substances.
Attini
Taxonomic tribe of two genera of leaf-cutting ants (Atta,15 species; Acromyrmex,24 species) that are able to cultivate fungi in subterranean gardens of their nests.
autoinflammatory diseases
Diseases due to unregulated inflammation in the absence of infection; they can have a variety of causes, including inherited genetic defects.
Autopolyploid
A polyploid that has multiple and identical or nearly identical sets of chromosomes (genomes). A polyploid species with genomes derived from the same original species.
Azo compounds
A class of compounds with the general structure R-N=N-R’.
Back mutation
A second mutation at the same site in a gene as the original mutation, which restores the wild-type nucleotide sequence.
Backcross
The cross of an F1 hybrid to one of the parental types. The offspring of such a cross are referred to as the backcross generation or backcross progeny. (See also Testcross.)
Balanced lethal
Lethal mutations in different genes on the same pair of chromosomes that remain in repulsion because of close linkage or crossover suppression. In a closed population, only the trans-heterozygotes (l1 + / + l2) for the lethal mutations survive.
Balancer chromosome
In Drosophila genetics, a dominantly marked, multiply-inverted chromosome that suppresses recombination with a homologous chromosome that is structurally normal.
Bcr–Abl tyrosine kinase
Constitutively active tyrosine kinase fusion protein caused by a chromosomal translocation—the Philadelphia chromosome— between Bcr with the Abl tyrosine kinase genes associated with chronic myeloid leukemia.
bioaugmentation
The use of pollutant-acclimated microbes or genetically engineered microbes for bioremediation.
Biological filtration
Removal of dissolved organic substances from water by means of biofilms. The microorganisms absorb biodegradable material and convert it into metabolites (preferably CO2 and water) and biomass. This principle is generally applied to biological drinking and waste water purification.
biomotor abilities
Abilities whereby the body can perform a range of activities, such as strength, speed, and endurance. Biomotor abilities are influenced by training and may be genetically determined.
Bioreporters
Living and usually genetically engineered microbial cells producing a detectable signal in reponse to a specific (chemical or physical) agent present in their environment.
Bithorax complex
One of two gene clusters in Drosophila that contain Hox genes; genes in the Bithorax complex control the differences among the abdominal and thoracic segments of the body.
Blau syndrome
An inherited granulomatous disease caused by gain-offunction mutations in the NOD2 gene.
BRCA1, BRCA2
Two tumor suppressor genes associated with inherited susceptibility to breast and ovarian cancers.
Brown-Vialetto-Van Laere syndrome
A disorder of the nervous and muscle systems due to genetic defects in the genes encoding riboflavin transporters RFVT2 and 3.
c-Oncogene
A cancer-causing gene encoded in cellular genomes: may be formed via mutagenesis of a gene that does not cause cancer, known therefore as a proto-oncogene. (Chapter 7)
cAMP response element-binding protein (CREB)
Protein that mediates effects of cyclic AMP on gene transcription.
cancer-critical genes
Genes whose alteration contributes to the causation or evolution of cancer by driving tumorigenesis. capsid Protein coat of a virus, formed by the self-assembly of one or more types of protein subunit into a geometrically regular structure.
carcinogenesis
The generation of cancer.
Cdc42
Member of the Rho family of monomeric GTPases that regulate the actin and microtubule cytoskeletons, cell-cycle progression, gene transcription, and membrane transport.
center-surround receptive field
A visual receptive field with a circular center region and a surround region forming a ring around the center; stimulation of the center produces a response opposite that generated by stimulation of the surround.
central pattern generator
A neural circuit that gives rise to rhythmic motor activity.
channelopathy
A human genetic disease caused by alterations in the structure and function of ion channels.
chemiosmosis
A mechanism that uses a proton gradient across a cytoplasmic membrane to generate ATP.
Chimera (plant)
Part of a plant with a genetically different constitution as compared with other parts of the same plant. It may result from different zygotes that grow together or from artificial fusion (grafting); it may either be pernical, with parallel layers of genetically different tissues, or sectorial.
Chorionic biopsy
A procedure in which cells are taken from an embryo for the purpose of genetic testing.
Chromosome Theory of Heredity
The theory that chromosomes carry the genetic information and that their behavior during meiosis provides the physical basis for the segregation and independent assortment of genes.
chronic infantile neurologic cutaneous and articular syndrome (CINCA)
An autoinflammatory disease due to defects in the gene NLRP3, one of the components of the inflammasome.
cis-trans test
The construction and analysis of cis and trans heterozygotes of pairs of mutations to determine whether the mutations are in the same gene or in two different genes. For the test to be informative, the cis heterozygote must have the wild-type phenotype. If this condition is met, the two mutations are in the same gene if the trans heterozygote has the mutant phenotype, and they are in two different genes if the trans heterozygote has the wildtype phenotype.
clock gene
A gene that is critically involved in the molecular mechanism of the circadian rhythm; clock genes are translated into proteins that regulate their own transcription, and their expression rises and falls over a cycle of about 24 hours.
Co-repressor
An effector molecule that forms a complex with a repressor and turns off the expression of a gene or set of genes.
codominant
Describes the situation in which the two alleles of a gene are expressed in roughly equal amounts in the heterozygote. Most genes show this property, including the highly polymorphic MHC genes.
Coefficient of relationship
The fraction of genes two individuals share by virtue of common ancestry.
combinatorial control
Use of combinations of a limited repertoire of regulatory proteins to provide gene-specific regulation of many individual genes.
Comparative genomics
The branch of genomics that compares the structure and function of the genomes of different species.
Complementation
The ability of gene products of two different, individually nonreproducing mutants to interact functionally in the same cell to permit virus reproduction. (Chapter 3)
Compound heterozygote
Person who carries two different mutations in different copies of the same gene.
Continuous variation
Variation not represented by distinct classes. Individuals grade into each other, and measurement data are required for analysis (cf. Discontinuous variation). Multiple genes are usually responsible for this type of variation.
Controlling element
In maize, a transposable element such as Ac or Ds that is capable of influencing the expression of a nearby gene.
Coordinate repression
Correlated regulation of the structural genes in an operon by a molecule that interacts with the operator sequence.
CpG islands
Clusters of cytosines and guanines that often occur upstream of human genes.
CRE-binding (CREB) protein
Transcription regulator that recognizes the cyclic AMP response element (CRE) in the regulatory region of genes activated by cAMP. On activation by PKA, phosphorylated CREB recruits a transcriptional coactivator (CREB-binding protein; CBP) to stimulate transcription of target genes.
Crossover unit
A measure of distance on genetic maps that is based on the average number of crossing-over events that take place during meiosis. A map interval that is one crossover unit in length (sometimes called a centiMorgan) implies that only one in every hundred chromatids recovered from meiosis will have undergone a crossing-over event in this interval.
cryoelectron microscopy
Technique for examining a thin film of an aqueous suspension of biological material that has been frozen rapidly enough to create vitreous ice. The specimen is then kept frozen and transferred to the electron microscope. Image contrast is low, but is generated solely by the macromolecular structures present.
Cut-and-paste transposon
A transposable element that is excised from one position in the genome and inserted into another position through the action of a transposon-encoded enzyme called the transposase.
cytidine deaminase activity (CDA)
An enzymatic activity exhibited by AID-APOBEC family proteins of agnathan species that may mediate rearrangement and assembly of complete VLR genes.
Cytogenetics
Area of biology concerned with chromosomes and their implications in genetics.
Cytoplasmic inheritance
Hereditary transmission dependent on the cytoplasm or structures in the cytoplasm rather than the nuclear genes; extrachromosomal inheritance. Example: Plastid characteristics in plants may be inherited by a mechanism independent of nuclear genes.
Derepression
The process of turning on the expression of a gene or set of genes whose expression has been repressed (turned off).
diathesis–stress hypothesis of mood disorders
A hypothesis suggesting that depression is caused by a combination of genetic predisposition and environmental stress.
Disulfides (RSSR’)
A class of compounds of the general structure RSSR’.
Dominant selectable marker gene
A gene that allows the host cell to survive under conditions where it would otherwise die.
Dominant-negative mutation
A mutant allele of a gene that interferes with the function of a wild-type allele so that individuals heterozygous for the mutant and wild-type alleles have a mutant phenotype.
Dorsal protein
Transcription regulator of the NFκB family regulating gene expression and involved in establishing the dorsoventral axis in the embryo.
Dosage compensation
A phenomenon in which the activity of a gene is increased or decreased according to the number of copies of that gene in the cell.
Duplication
The occurrence of a segment more than once in the same chromosome or genome; also, the multiplication of cells.
E2F protein
Transcription regulatory protein that switches on many genes that encode proteins required for entry into the S phase of the cell cycle.
Effector molecule
A molecule that influences the behavior of a regulatory molecule, such as a repressor protein, thereby influencing gene expression.
egg-polarity genes
Genes in the Drosophila egg that define the anteroposterior and dorsoventral axes of the future embryo through the creation of landmarks (mRNA or protein) in the egg that provide signals organizing the developmental process.
Ehlers-Danlos syndrome
A group of genetic diseases characterized by stretchy skin and loose joints.
electrochemical cell
A device that uses redox reactions to generate electricity or an electrical current to drive a chemical reaction.
electroencephalogram (EEG)
A measurement of electrical activity generated by the brain and recorded from the scalp.
electron groups
A general term for lone pairs, single bonds, multiple bonds, or lone electrons in a molecule.
Epigenetics
Study of mitotically and/or meiotically heritable changes in phenotype, which are independent from genetic variation.
Epistasis
Interactions between products of nonallelic genes. Genes suppressed are said to be hypostatic. Dominance is associated with members of allelic pairs, whereas epistasis results from interactions of the products of nonalleles.
epistasis analysis
Analysis to discover the order in which the genes act, by investigating if a mutation in one gene can mask the effect of a mutation in another gene when both mutations are present in the same organism or cell.
Eugenics
The application of the principles of genetics to the improvement of humankind.
excitable cell
A cell capable of generating action potentials of electric current.
excitable membrane
Any membrane capable of generating action potentials. The membrane of axons and muscle cells is excitable.
experiment
A highly controlled procedure designed to generate observations that may support a hypothesis or prove it wrong.
Expression domain
The region of a riboswitch that can fold into two conformations, one facilitating gene expression and the other blocking gene expression.
F1
The first filial generation; the first generation of descent from a given mating.
F2
The second filial generation produced by crossing inter se or by self-pollinating the F1. The inbred “grandchildren” of a given mating, but in controlled genetic experimentation, self-fertilization of the F1 (or equivalent) is implied.
Familial combined hyperlipoproteinemia
A genetic predisposition to type II and type IV hyperlipoproteinemia.
familial Mediterranean fever (FMF)
A severe autoinflammatory disease, inherited as an autosomal recessive disorder. It is caused by mutation in the gene (MEFV) that encodes the protein pyrin, which is expressed in granulocytes and monocytes. In patients with this disorder, defective pyrin is thought to spontaneously activate inflammasomes.
filopodium (plural filopodia) (microspike)
Thin, spike-like protrusion with an actin filament core, generated on the leading edge of a crawling animal cell.
Fission
A mode of cell division among the prokaryotes in which the genetic material of the mother cell is first duplicated and then apportioned equally to the two daughter cells.
Flux control
Control of the transport rate of a transporter by the substrate.Magnesium ions are, for instance, able to bind to various magnesium transporters shutting off their activity when the cytoplasmic magnesium concentration is sufficiently high. Flux control functions in addition to other regulatory processes, e.g., control of gene expression.
Founder principle
The possibility that a new, small, isolated population may diverge genetically because the founding individuals are a random sample from a large, main population.
frontal eye field (FEF)
A cortical area in the frontal lobe involved in the generation of saccadic eye movements.
Gain-of-function mutation
A mutation that endows a gene product with a new function.
Gene addition
The addition of a functional copy of a gene to the genome of an organism.
Gene chip
A small silicon wafer or other solid support containing a large number of oligonucleotide or cDNA hybridization probes arranged on its surface in a specific pattern, or microarray.
Gene flow
The spread of genes from one breeding population to another by migration, possibly leading to allele frequency changes.
gene fusion
The enzymatic attachment of one gene, or part of a gene, to another.
Gene pool
The sum total of all different alleles in the breeding members of a population at a given time.
Gene replacement
The incorporation of a transgene into a chromosome at its normal location by homologous recombination, thus replacing the copy of the gene originally present at the locus.
general adaptation syndrome
(GAS)—A syndrome conceptualized by Hans Selye that explains the body’s response to stressors, including physiological and psychological stress. The GAS is often cited as being a foundational component of periodization theory.
general strength
The strength of the whole muscular system.
generalized seizure
Pathologically large and synchronous neural activity that spreads to encompass the entire cerebral hemispheres. See also partial seizure.
generation time
The time required for a cell or population to double in number.
Genetic bottleneck
A descriptive term evoking the extreme selective pressure on small populations that results in loss of diversity, accumulation of selected mutations, or both. (Chapter 10)
Genetic equilibrium
Condition in a group of interbreeding organisms in which the allele frequencies remain constant over time.
genetic instability
Abnormally increased spontaneous mutation rate, such as occurs in cancer cells.
genetic screen
Procedure for discovery of genes affecting a specific phenotype by surveying large numbers of mutagenized individuals.
Genetic selection
The exposure of a cell or an organism to environmental conditions in which it can survive only if it carries a specific gene or genetic element.
genetic sex
The sex of an animal or person based solely on genotype.
Genetic shift
Diversity in viral genomes that arises as a result of re-assortment of genome segments or recombination between genomes. (Chapter 10)
genetic testing
Techniques for determining which genes are in a cell’s genome.
genome annotation
Process attempting to mark out all the genes (protein-coding and noncoding) in a genome and ascribing functions to each.
genomic imprinting
Phenomenon in which a gene is either expressed or not expressed in the offspring depending on which parent it is inherited from.
genus (plural: genera)
The first name of the scientific name (binomial); the taxon between family and species.
Germ-line (heritable) gene therapy
Treatment of an inherited disorder by adding functional (wild-type) copies of a gene to reproductive (germ-line) cells of an individual carrying defective copies of that gene (cf. Somatic-cell [nonheritable] gene therapy).
Gilbert syndrome
Benign hyperbilirubinemia caused by a promoter mutation in the gene for bilirubin- UDP-glucuronyl transferase.
Green chemistry
The design and implementation of chemical products and processes that reduce waste and minimize or eliminate the generation of hazardous substances.
group transfer potential
A measure of the ability of a compound to donate an activated group (such as a phosphate or acyl group); generally expressed as the standard free energy of hydrolysis.
H-2 locus, H-2 genes
The major histocompatibility complex of the mouse. Haplotypes are designated by a lower-case superscript, as in H-2b.
haploinsufficient
Describes the situation in which the presence of only one normal allele of a gene is not sufficient for normal function.
Hardy–Weinberg Principle
Mathematical relationship that allows the frequencies of genotypes in a population to be predicted from their constituent allele frequencies; a consequence of random mating.
Hedgehog protein
Secreted extracellular signal molecule that has many different roles controlling cell differentiation and gene expression in animal embryos and adult tissues. Excessive Hedgehog signaling can lead to cancer.