AP BIo Genetics

difference between mitosis and meiosis

• In mitosis, one cell splits to produce two genetically identical cells
• In meiosis, there are 2 fissions that produce 4 gametes with 1/2 chromosom 
• In meiosis, prophase, metaphase, anaphase, and telophase are repeated
• Meiosis occurs in the sexual reproduction process
• Mitosis is the asexual reproductive process of cells

The Purpose...
-- Mitosis produces the cells within our bodies
-- Meiosis produces the gametes such as sperm cell and egg

Reproduction Order

• INTERPHASE
• PROPHASE (1 AND 2 IN MEIOSIS)
• METAPHASE (1 AND 2 IN MEIOSIS)
• ANAPHASE (1 AND 2 IN MEIOSIS)
• TELOPHASE/ CYTOKINESIS (1 AND 2)

Mitosis happenings

• Interphase: long chromosome, homeostasis
• Prophase: nucler membrane disappears, 
• chromatids line up on equator (spindle fibers)
• Anaphase: centromere splits, chromosomes apart
• Telophase: spindle fibers disappear, new membrane

In meiosis, prophase through telophase are repeated

of special note...

• Two particular events create genetic variation:
• PROPHASE I: Crossing over between non-sister chromatids
• METAPHASE I: Independent assortment of chromosomes

There are TWO types of cells in our bodies:
HAPLOID: cells produced by meiosis (replica)
DIPLOID: cells produced by mitosis (germ cell)

--Diploid cells contain TWO complete sets of chromosomes

--Haploid cells end with half the number of chromosomes

Chromosomes???
--Homologous chromosomes contain a maternal and paternal half (meiosis)

-- Duplicated chromosomes are essential carbon copies of split DNA (mitosis)

Chromatids and more...

• CHROMATIN: DNA wound around specific proteins (histones)
• CHROMOSOME: Basically a massive piece of chromatin
• that is structurally independent and contains specific genes
• CHROMATID: One half of a chromosome joined together by  
• a centromere that is made during cell division