1. Warm-Up (11/12)
On the piece of white paper from the back, answer the following question.
Name
Date
Period
How is mitosis different in prokaryotic versus eukaryotic cells?
Hint: go back to the difference between prokaryotes and eukaryotes during replication.

2. Let’s do Meiosis! (make sperm or eggs)
Why?: to increase genetic diversity during sexual reproduction
How?
Method #1: share your genes with another person to make a baby (don’t just make a baby by duplicating yourself)
Method #2: Make your gametes (sperm or eggs) as genetically distinct from one another as possible.

3. Meiosis: Part I 2n 2n n = 4 n = 4 1m 1p 1p 3p 1m 2p 2m 2p 2m 3p 3m 4p
4-chrosome somatic cell (a cell which forms via mitosis), with a maternal (m) version (“a homologue”) and a paternal (p) version of each chromosome 2n
n = 4
Chromosome pairs line up in the middle of the cell randomly; the maternal homologue can be either on one side or another for each chromosome. 2n
n = 4

4. In a 4-chromosome cell, how many different combinations can be made?
Meiosis: Part II 1m 1p 1p 1m 2p 2m 2p 3p 3m 2m 3p 4m 3m 4p 4m 4p
Cell divides into two, each with of the four chromosomes, but different combinations of homologues. 2n
n = 4
Two genetically distinct gametes are born. Each have only four chromosomes, not paired. 1n
n = 4
In a 4-chromosome cell, how many different combinations can be made?
In a 23-chromosome human cell, how many different combinations can be made?

5. Critical-Thinking Question #1
Do this in your notebook. Quit reading instructions, just read the question. Go on, quit reading this sentence all ready. Please. Just start reading below.
Illustrate how a single somatic cell with 2 chromosomes can generate four genetically distinct gametes by drawing the process of meiosis.

6. Method #3 to increase genetic diversity
“Crossing Over”
Method #3 to increase genetic diversity 1m 1p 1p 2p 2m 1m 2p 2m 3p 3m 3p 3m 4m 4p 4m 4p

7. Share and Discuss
Discuss this question with your partner and write or represent it. I will call on three people to share their partners’ answers.
How does meiosis contribute to increased genetic diversity in a population?

8. Closure
On the piece of white paper from the back, answer the following question:
Name
Date
Period
State two events during meiosis that contribute to increased genetic diversity and explain how they function to increase variation in a population.
Scale 1 – 10