1. Cell Reproduction

2. Cell Reproduction – Meiosis 4.5
Body cells or ________ cells are _______, which means they have ___ sets of chromosomes.
One set came from the _______ parent and the other came from the ________ parent.
somatic
diploid 2
male
female

3. Diploid Cells
Since diploid cells have 2 sets of chromosomes , they are represented by _____. In humans, this number is ____.
Somatic diploid cells reproduce to make ____ identical copies of themselves in the process called ________.
Somatic cell
reproduction 2n 46 2
Humans
mitosis

4. Haploid Cells Cells with only 1 set of chromosomes are
said to be ________.
These cells are
represented by ____.
In humans, this
number is ____.
Only the sex cells
or ________ of a
multicellular organism are haploid.
haploid n 23
gametes

5. Meiosis (not mitosis)
The gametes of an organism are produced in a type of cell division called _________.
Meiosis occurs in the _________ of the cell cycle.
M = mitosis for somatic body cells
M = meiosis for making gametes
meiosis
M phase

6. Meiosis During meiosis, a nucleus undergoes ___ rounds of division.
A diploid cell becomes ____, _______ daughter cells. 2 4
haploid

7. Meiosis in Humans
Meiosis occurs in the reproductive organs. Testes in males (sperm) Ovaries in females (egg/ovum)
Diploid germ cell
In testicle or ovary
Haploid
sperm or
egg
cells

8. Meiosis Animation

9. Comparing Mitosis & Meiosis
Purpose of Process
Growth & Repair
Formation of gametes
Type of cells it occurs in
Somatic
Germ cell in testes
Germ cell in ovary
Chromosome number in parent cell
2n (46)
Number of times the DNA replicates 1
Number of nuclear/cellular divisions 2
Number of daughter cells produced 4
Chromosome number in daughter cells
n (23)
Daughter cells identical or different from parent cell
identical
different
When synapsis and crossing over occurs
never
Prophase I

10. Memory Aid miTosis mainTains the chromosome number (2n2n)
meiOsis lOwers the chromosome number from two sets to one set (2nn)