Do Now: compare these two, how are they similar? How are they different?

Picturing Mitosis and Meiosis

Mr. Lin

2.6.08

Mitosis Steps

1. Parent cell (duplicates / copies / replicates) its DNA

2. Cell divides into 2, DNA is divided into 2 daughter cells

Mitosis

1. Parent cell (duplicates / copies / replicates) its DNA

2. Cell divides into 2, DNA is divided into 2 daughter cells

Mitosis

1. Parent cell (duplicates / copies / replicates) its DNA

2. Cell divides into 2, DNA is divided into 2 daughter cells

Mitosis

1. Parent cell (duplicates / copies / replicates) its DNA

2. Cell divides into 2, DNA is divided into 2 daughter cells

Meiosis Steps

1. Parent cell replicates its DNA

2. Cells and DNA divide into 2 cells.

3. Cells and DNA divide again for a total of 4 daughter cells.

Meiosis

1. Parent cell replicates its DNA

2. Cells and DNA divide into 2 cells.

3. Cells and DNA divide again for a total of 4 total daughter cells.

Meiosis

1. Parent cell replicates its DNA

2. Cells and DNA divide into 2 cells.

3. Cells and DNA divide again for a total of 4 total daughter cells.

Meiosis creates variation

• Crossing-Over

Meiosis creates variation

• Independent Assortment

42Number of daughter cells

Lots! Crossing-over and independent sorting

Little or NoneVariation

½ set of chromosomes

X H T

Full set of chromosomes

XX HH TTDaughter cells

end with

21# of divisions

Full set of chromosomes

XX HH TTFull set of chromosomes

XX HH TTParents cells

start with

MeiosisMitosis