Glossary - genetics Flashcards
an inherited characteristic that improves an organism’s ability to survive and repro¬duce in a particular environment
adaptation
the clumping together of red blood cells or microorganisms in the presence of a specific antibody
agglutination
an inherited metabolic disorder that affects the metabolism of certain amino acids and leads to darkening of the urine due to the excretion of homogentisic acid
alkaptonuria
one of the alternative forms of a gene
allele
the formation of two species that occurs when sub-populations of a species are reproductively isolated due to geographic separation
allopatric speciation
– the basic building block of proteins
amino acid
a procedure used to recover a sam¬ple of the amniotic fluid surrounding a fetus in the womb for the purpose of performing genetic tests
amniocentesis
having no definite shape, resembling the form or the type of movement of an amoeba
amoeboid
the third stage of mitosis when sister chromatids split and move toward opposite poles of the cell
anaphase
a protein produced by immune cells that binds to a specific antigen to neutralize its effects
antibody
the triplet of nucleotides in the transfer RNA that is complementary to a triplet base (codon) in the messenger RNA
anticoden
a substance that evokes the production of an antibody
antigen
a type of reproduction involving only one parent without the fusion of gam¬etes (sperm and egg); usually produces genetically identical offspring
asexual reproduction
a temporary energy storage molecule for most cells
ATP (adenosine triphosphate)
a controlled digestion process in which a cell’s own subcellular organelles are broken down and recycled
autophagy
any eukaryotic chromosome other than a sex chromosome
autosome
a virus that infects bacteria
bacteriophage
a type of asexual reproduction in which a parent cell divides into two genetically iden¬tical daughter cells
binary fission
the theorem that describes the expansion of any power of a binomial, that is, (a + b)m
binomial theorem
the removal of a piece of tissue from a living body for diagnostic studies
biopsy
the use of molecular techniques in living organisms to manufacture useful products
biotechnology
a historically influential but factually incorrect notion that organisms contain a blend of traits from their parents
blending inheritance
a type of asexual reproduction in which a new organism grows from the body of the par¬ent, eventually detaches from the parent, and lives independently
budding
a disease caused by abnormally rapid pro¬liferation of body cells
cancer
a sugar that contains carbon, hydro¬gen, and oxygen in the ratio 1:2:1 (CH2O)n
carbohydrate
in genetics, an individual who is heterozygous for a particular trait
carrier
the basic structural and functional unit of liv¬ing organisms
cell
a series of orderly events a eukaryotic cell goes through, from a dividing parent cell to two daughter cells
cell cycle
the theory that cells are the basic unit of life and all cells come from preexisting cells
cell theory
the metabolic pathways by which food molecules are broken down and energy is released and harvested by the cell
cellular respiration
a large organelle in plant cells that stores the waste products of metabolism, maintains turgor pressure, and maintains growth
central vacuole
a laboratory technique in which a sample is spun around a central axis at high speed to separate its components based on their size, density, or weight
centrifugation
a structure in animal cells composed of bundles of microtubule triplets during cell division
centriole
a region where sister chromatids (duplicated chromosomes) are joined and to which spindle fibers are attached during cell division
centromere
a procedure in which a sample of the fetal chorionic villi (part of the placenta) is removed for genetic testing
chorionic villus sampling (CVS)
one of a pair of identical chromosomes after DNA replication in the cell cycle
chromatid
the dispersed DNA–protein complex that makes up eukaryotic chromosomes
chromatin
a laboratory procedure used to separate and isolate substances in a mixture based on the physical or chemical properties of the constituents
chromatography
a complex structure in the nucleus of eukaryotes or in the nucleoid region of prokaryotes that is comprised of DNA
chromosome
short microscopic projections of the cell surface specialized for locomotion
cilia (sing.cilium)
the first few cell divisions of an animal zygote
cleavage
a specialized depression on the surface of a cell membrane, formed as a result of receptor-mediated endocytosis
coated pit
a type of inheritance in which two separate alleles at a locus are equally expressed and produce different phenotypic traits
co-dominance
a triplet of nucleotides in messenger RNA coding for a specific amino acid; the basic unit of the genetic code
codon
the transfer of the genetic material by joining two bacteria or protists
conjugation
an often fatal genetic disease char¬acterized by the production of thick mucus that obstructs various ducts in different organs, leading to infection and interference of important functions
cystic fibrosis
the cytoplasmic division of a cell at the end of mitosis or meiosis, bringing about the separa¬tion into two daughter cells
cytokinesis
relating to the science of cytology, a sub-discipline of biology that studies the microscop¬ic structure of cells
cytological
the content of a cell inside the plasma membrane and outside the nucleus
cytoplasm
a network of protein fila¬ments in the cytoplasm of a cell that serves various functions in support, movement, and transport; the system includes microtubules, intermediate fila¬ments, and microfilaments
cytoskeletal elements
the fluid portion of the cytoplasm
cytosol
a five-carbon sugar that is a building block of DNA and some nucleotides
deoxyribose
the genetic material for all organisms except the RNA virus
DNA (deoxyribonucleic acid)
describes an allele that determines the phenotype when the genotype is heterozygous
dominant
the spiral shape of a double-stranded DNA molecule
double helix
the production of a second copy of a particular sequence of DNA
duplication
the method of distinguishing mol¬ecules, such as a mixture of proteins or DNA, according to their motility in a gel-like substance in an electric field
electrophoresis
related to an embryo, or being in the state of an embryo
embryonic
a process by which liquids or solid particles are taken up by a cell through invagination of the plasma membrane
endocytosis
the inner epithelial lining of the uterus
endometrium
a network of tubules that is part of the endomembrane system in eukaryotic cells specializing in the synthesis and modification of biological molecules
endoplasmic reticulum
the theory that ancient large eukaryotic cells ingested small prokaryotes, which became subcellular organelles (such as mitochon¬dria and chloroplasts) of the large host cell
endosymbiosis
the scientific study of changes in the inheritance of traits that occur without changes in the DNA sequence
epigenetics
an interaction between two genes in which one gene alters the expression or effect of another gene
epistasis
a hormone produced by the kidney in response to low levels of blood oxygen that stimu¬lates the production of red blood cells by the bone marrow
erythropoietin
the study or practice of altering a popu¬lation, especially of humans, by controlling fertility and selective breeding for desirable traits
eugenics
the process of change by which new species develop from preexisting ancestral species over time
evolution
a process by which a vesicle within a cell fuses with the plasma membrane and releases its contents to the outside
exocytosis
the nucleotide sequence of a gene that codes for a protein
exon
an inherited meta¬bolic disorder that results in high levels of blood cholesterol; the disorder is caused by a lack or mal-function of receptors for the low-density lipoprotein (LDL) that removes cholesterol from the blood
familial hypercholesterolemia
long, whip-like append¬ages that propel and move cells
flagella (sing.flagellum)
the branch of genomics that analyzes the biological function of genes and their products
functional genomics
a hypothetical particle postulated to be the hereditary unit in the (now recognized as incor¬rect) theory of pangenesis
gemmule
a unit of heredity consisting of a specific sequence of nucleotides in DNA (or RNA in some viruses)
gene
the process by which the infor¬mation encoded in a gene is converted first into messenger RNA and then to a protein
gene expression
the code relating nucleotide triplets in messenger RNA (or DNA) to amino acids in proteins
genetic code
a change in the allele frequency in a population that occurs by chance
genetic drift
a sub-discipline of biology that studies genes and heredity
genetics
the full set of DNA in a cell or organism
genome
the DNA constituting the genome of a cell or an organism, as distinguished from extra chromosomal DNAs, such as plasmids
genomic DNA
the genetic makeup (set of alleles) of an organism
genotype
a reproductive cell (gamete), or one of its precursors, of a multicellular organism
germ cell
the lineage of cells from which gametes are derived
germ line
