Mitosis & Meiosis Review
Name___________________
1. Define mitosis and meiosis:
MitosisCell division in somatic cells to produce identical daughter cells
MeiosisCell division in sex cells to produce novel combinations of chromosomes. Sex cells
have half the number of chromosomes. Generates diversity due to new allele
combinations
2. What does mitosis produce? What does meiosis produce?
MitosisIdentical daughter cells
MeiosisSex cells with half the number of chromosomes
3. What are the 2 periods of the cell cycle called?
Interphase and Mitosis
4. Period 1 of the cell cycle (Interphase) includes 3 parts. List these 3 parts and
give a brief explanation of what is occurring at each stage.
G1 growth phase
S1 DNA replication phase
G2 growth phase
5. Period 2 of the cell cycle (Mitosis) includes 4 parts. List these 4 parts and
describe what is happening at each stage.
Stage 1: Prophase Chromosomes condense
Stage 2: Metaphase Chromosomes align on equator
Stage 3: Anaphase Chromosomes pull apart
Stage 4: Telophase Cell divides Chromosomes enclosed in new nucleus
Mitosis starts with 1 body cell, how many body cells do you end up with? Are these
identical or different from the original body cell?
100 trillion Not identical due to different genes being turned on (differentiation)
What period of the cell cycle does a cell spend most of its time in?
Interphase
6. What is one cause of cancer, related to the cell cycle?
When cell division is not halted cells multiply out of control
Mitosis or Meiosis
7. Do bacteria reproduce through mitosis or meiosis?
Mitosis (Binary fission)
8. Once an egg has been fertilized (zygote), and the cell starts replicating to grow
and develop, is this cell division an example of mitosis or meiosis?
Mitosis
9. The process by which a new organism is produced when sex cells from two
parents combine is called Fertilization. (mitosis or meiosis) Sex cells formed by
meiosis
10. Compare and contrast mitosis and meiosis. (So, give 3 similarities and
differences)
Results in same # of chromosomes Results in half # of chromosomes
Produces new somatic cells Produces sex cells
One reound of cell division (PMAT)
2 rounds of cell division (PMAT X 2)
Meiosis
11. How many phases of meiosis are there? List the phases.
Give a brief explanation of what is occurring at each stage.
There are two phases of cell division in Meiosis
PMAT 1 separates homologous pairs of chromosomes
PMAT 2 separates sister chromatids
12. What is crossing over? In what phase of meiosis does it occur?
When chromosomes recombine and swap DNA resulting in the exchange of alleles
13. Why is crossing over so important?
Generates new combinations of alleles resulting in diversity
14. What is non-disjunction?
When sister chromosomes don’t separate and both get “dragged” into one sex cell
15. How does meiosis provide for genetic variation?
New pairs of alleles are generated that results in new combinations of traits
16. What is Diploid? What is Haploid?
Diploid is when a cell has two of each chromosome (in somatic cells)
Haploid is when a cell only has one copy of each chromosome (in sex cells)