Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
22 Cards in this Set
- Front
- Back
|
allele
|
alternative form a gene - alleles occur at the same locus on homologous chromosomes
|
|
|
autosome
|
any chromosome other than the sex-determining pair
|
|
|
Barr body
|
dark-staining body in the nuclei of female mammals that contains condensed, inactive X chromosome
|
|
|
crossing-over
|
exchange of segments between nonsister chromatids of a tetrad during meiosis
|
|
|
diploid (2n) number
|
cell condition in which two of each type of chromosome are present
|
|
|
Down syndrome
|
is trisomy 21; an individual has 3 copies of chromosome 21; most cases, the egg contained 2 copies
|
|
|
dyad
|
chromosome composed of two sister chromatids
|
|
|
haploid (n) number
|
cell condition in which only 1 of each type of chromosome is present
|
|
|
homologous chromosome
|
member of a pair of chromosomes that are alike and come together in synapsis during prophase of the first meiotic division; a homolgue
|
|
|
homologue
|
member of a pair of chromosomes that are alike and come together in synapsis during prophase of the first meiotic division; a homologous chromosome
|
|
|
interkinesis
|
period of time between meiosis I and meiosis II during which no DNA replication takes place
|
|
|
Klinefelter syndrome
|
condition caused by the inheritance of XXY chromosomes
|
|
|
life cycle
|
recurring pattern of genetically programmed events by which individuals grow, develop, maintain themselves, and reproduce
|
|
|
meiosis, meiosis I, meiosis II
|
type of nuclear division that occurs as part of sexual reproduction in which the daughter cells receive the haploid number of chromosomes in varied combinations
|
|
|
nondisjunction
|
failure of homologous chromosomes or daughter chromosomes to separate during meiosis I and meiosis II, respectively
|
|
|
oogenesis
|
production of eggs in females by the process of meiosis and maturation
|
|
|
sex chromosome
|
chromosome that determines the sex of an individual; in humans, females have two X chromosomes, and males have an X and a Y chromosome
|
|
|
spermatogenesis
|
production of sperm in males by the process of meiosis and maturation
|
|
|
synapsis
|
pairing of homolgous chromosomes during meiosis I
|
|
|
tetrad
|
homologous chromosomes, each having sister chromatids that are joined during meiosis; also called bivalent
|
|
|
Turner syndrome
|
condition caused by the inheritcance of a single X chromosome
|
|
|
zygote
|
diploid cell formed by the union of two gametes; the product of fertilization
|
