Human somatic cells have ___ ____ of chromosomes

The two chromosomes in each pair are called ________ chromosomes.

Chromosomes in a homologous pair are the same ____ and ______ and carry genes controlling the same ______ _______.

x and y chromosomes

homologous pair of XX chromosomes

x and y chromosome

non-sex chromosomes, remaining 22.

Each pair of homologous chromosomes includes one chromosome from each

The ____ chromosomes in a human somatic cell are two sets of ___: one from the mother and one from the father

has two sets of chromosomes, in humans 2n = 46

an ordered display of the pairs of chromosomes from a cell

union of gametes (the sperm and the egg)

fertilized egg

only types of human cells produced by meiosis rather than mitosis

results in one set of chromosomes in each gamete

Meiosis reduces the number of chromosome sets from ____ ___ _____.

Like mitosis, meiosis is preceded by the

Two sets of cell divisions for meiosis.

The two cell divisions result in ____ daughter cells, rather than the _____ daughter cells in mitosis.

-Chromosomes begin to condense

point where crossing over has occurred.

Spindle fiber microtubules attach to kinetochore of chromosomes.

the paired chromosomes (tetrads) randomly line up at the metaphase plate, with one chromosome facing each pole

paired chromosomes

Pairs of homologous chromosomes separate- not the sister chromatids.

One chromosome moves toward each pole, sister chromatids remain attached at the centromere and move together.

Cleavage furrow forms

Spindle apparatus forms

Spindle fiber microtubules attach to kinetochore of chromosomes

Sister chromatids are arranged at the metaphase plate

Sister chromatids separate and move toward opposite poles

Nuclei form

At the end of meiosis, there are ____ daughter cells, each with a ____ set of chromosomes

During Metaphase I, the chromosomes line up completely randomly,

in prophase I combines DNA inherited from each parent

adds to genetic variation because any sperm can fuse with any ovum (unfertilized egg)