26 terms

Ch. 13- Meiosis

Vehicles that transmit genes from one generation to the next through fertilization. Sperm and eggs. Carrier of one set of chromosomes to make a somatic cell
On each gene, specific location along the length of a chromosome
Different versions of genes. Any of the alternative versions of a gene that may produce distinguishable phenotypic effects.
Homologuous Chromosomes
The two chromosomes in each pair
Homologous Chromosomes
Chromosomes in each pair are the same length and carry genes controlling the same inherited characters.
Somatic Cells
Any cell other than a gamete. Has 23 pairs of chromosomes. Each chromosome consists of a single long DNA molecule elaborately coiled in association with various proteins.
Somatic Cells
2 pair of 23 chromosomes in its final form. One set of chromosomes(23 chromosomes) is inherited from each parent.
An ordered display of the pairs of chromosomes from a cell.
Asexual Reproduction
One parent produces genetically identical offspring by mitosis.
A group of genetically identical individuals from the same parent.
Sexual Reproduction
Two parents produce offspring that have unique combinations of genes inherited from the two parents.
Sex Chromosomes
X or Y chromosomes that determine your sex. Females have a pair of X chromosomes(XX) and Males have one X and one Y chromosomes(XY)
The 22 pairs of chromosomes that do not determine sex.
Diploid Cell
2n Chromosomes 2 sets
Haploid Cell
1n Chromosomes 1 set
The union of gametes(the sperm and the egg)
The fertilized egg. Has one set of chromosomes from each parent. Diploid
Produces somatic cells by mitosis and develops into an adult
At sexual maturity, the ovaries and testes produce____________?
haploid gametes
The only types of human cells produced by meiosis, rather than mitosis
Results in one set of chromosomes in each gamete.
Fertilization and Meiosis
alternate in sexual life cycles to maintain chromosome number.
reduces the number of chromosome sets from diploid to haploid
2 sets of cell divisions, meiosis 1 and meiosis 2. The 2 cell divisions result in 4 daughter cells, rather than the 2 daughter cells in mitosis. Each daughter cell has only half as many chromosomes as the parent cell.
Meiosis 1
Seperates homologous chromosomes; it is called the reductional division.
Meiosis 2
Seperates sister chromatids; it is the equational division.