Meiosis - the form of cell division that creates sex cells
meiosis metaphase I
3rd stage of meiosis I; the tetrads line up in the middle of the cell
meiosis telophase 2
4 haploid cells result after cytokinesis
trait
A characteristic (for example blue eyes) that an organism can pass on to its offspring through its genes.
meiosis telophase I
A nuclear envelopes form around the chromosomes. Chromosomes uncoil. Spindles disappear.
haploid
(genetics) an organism or cell having only one complete set of chromosomes
diploid
(genetics) an organism or cell having two sets of chromosomes or twice the haploid number
bivalent
a pair of homologous chromosomes - another term for tetrad
egg cell
also called ovum; female gamete
meiosis
cell division that produces gametes (sex cells)
meiosis prophase I
chromosome pairs line up in tetrads, where crossing-over occurs
meiosis interphase
chromosomes duplicate
meiosis metaphase 2
chromosomes line up in the center of each cell like in mitosis
allele
different forms of a gene
zygote
diploid cell formed when a sperm fertilizes an egg
karyogram
shows the chromosomes of an organism in homologous pairs of decreasing length
meiosis anaphase 2
sister chromatids separate again
tetrad
structure containing 4 chromatids that forms during meiosis
sperm cell
the male gamete ( in animals), contains half the genes of a normal cell
independent assortment
the random distribution of the pairs of genes on different chromosomes to the gametes
sister chromatids
two strands of a copied chromosome joined at the middle by a centromere
daughter cells
new cells produced by cell division
gene
A segment of DNA on a chromosome that codes for a specific trait
homologous
Chromosomes that have the same sequence of genes and the same structure
replication
Copying process by which a cell duplicates its DNA
crossing-over
exchange of genetic material between homologous chromosomes during prophase I of meiosis