Chapter 13: Meiosis + Sexual Reproduction

Gametes

Reproductive cells that transmit genes

Somatic cells go through _____, while gametes go through _____.

mitosis, meiosis

locus

gene’s specific location along chromosome

genetic variation is…

an important consequence of sexual reproduction.

life cycle

ancestral sequence of stages in the reproductive history of an organism

karyotype

ordered display of homologous chromosomes in a somatic cell

homologous chromosomes(homologs)

chromosomes in a pair that have the same length, centromere position, staining pattern

what is the chromosomal difference separating males and females?

XY vs. XX chromosomes

Diploid cell(2n)

any cell with two chromosome sets

Haploid cells(n)

any cell with a single set of chromosomes

somatic cells are _____, while gametes are ______.

diploid, haploid

fertilization

haploid sperm from father fuses with haploid egg from mother, creating a zygote

a zygote is a ______ cell formed from two ______ cells.

diploid, haploid

Meiosis _____ the chromosome count, while fertilization _____ it.

reduces(n=23), restores(2n=46)

alternation of generations

specialized life cycle in which both mitosis and meiosis occur to form a zygote

meiosis I

homologous chromosomes are seaparated and 2 daughter cells are made

meiosis II

sister chromatids in each daughter cell separate to form 2 more daughter cells, forming 4 daughter cells by the end of meiosis

consequences of crossing over

creates new combinations of traits on each chromosome

consequences of genetic recombination

introduces genetic variation through independent assortment of chromosomes

spermatogenesis

production of sperm, forms 4 spermatozoa from one diploid germ cell

oogenesis

production of ova, forms one ovum and 3 polar bodies from one diploid germ cell