bio

What are the three reasons for cell divison

grow, repair, reproduction

What does meiosis produce

gametes (sperm and egg)

What is meiosis

cell division in sex cells

What is the purpose of meiosis

produce 4 genetically different haploid sex cells

How many chromosomes are in each gamete

23

How many chromosomes are in each body cell

46

What are homologous chromosomes

corresponding chromosomes, one comes from male, one comes from female

What is a diploid

cell that contains 2 sets of chromosomes

What are examples of diploids?

Every cell in the body but not sex cells

What is a haploid and what are examples

cell that contains 1 set of chromosomes; sperm and ova

what occurs in meiosis 1

reduction division, you end up with ½ of chromosomes you start with

Interphase 1

cell grows and replicates dna for division

What occurs during prophase 1

Homologous chromosomes stack randomly, crossing over

What do tetrads form

4 chromatids

What is crossing over

homologous chromosomes line up next to each otehr and chromatids exchange DNA pieces

What is chiasmata

where non sister chromosomes cross over each other

What occurs during metaphase 1

Independent assortment, homologous chromosomes stack up in the middle of the cell

What does anaphase 1 do

homologous chromosomes separate and move to the ends of the cell

what happens during meiosis 2

4 genetically different haploid gametes are produced

What are the 4 female gametes

3 are polar bodies which are aborted eggs, and one is ovum

What do the extra 3 female sex cells do

the polar bodied eggs keep oocyte (immatre egg cells) rich and conserve energy