1. How many stages of cell division do you see in this image?
Genetics Unit: Mitosis
How many stages of cell division do you see in this image?

3. Cell Cycle Mitosis will be our main focus.
First, we will look at Interphase… )

4. Interphase Longest stage of cell division (90% of cell cycle)
Nucleus is visible
Cell is growing and DNA is being replicated. )

5. Most of these cells are in Interphase
Interphase: 3 Phases
G1: Cell is Growing
S: DNA is Synthesized (DNA Replication)
G2: Organelles duplicate in preparation for division )

6. Key Vocabulary DNA molecules are packaged into . chromosomes
Human (body cells) have 46
Human (sperm or eggs) have 23
Chromosomes are made of a material called .
chromosomes
somatic cells
chromosomes.
gametes
chromosomes.
chromatin

7. Key Vocabulary Chromatin is composed of and .
It is supercoiled around proteins, called .
Together the DNA and histone molecules form bead-like structures called
DNA
proteins
histones
nucleosomes

8. Key Vocabulary The chromosome is duplicated.
Each duplicated chromosome consists of two
These are connected by a .
sister
chromatids
centromere

9. Mitosis (M Phase) Prophase Metaphase Anaphase Telophase
The M Phase consists of:
Mitosis and Cytokinesis
Four Stages of Mitosis:
Prophase
Metaphase
Anaphase
Telophase
For Homework: Left-side IntNB assignment: Write an Acrostic Poem for the four stages of Mitosis

10. Preparing for Division
Late Interphase: G2
Centrosomes (with centriole pairs)
Nuclear membrane still visible
Nucleolus
Chromatin has been replicated

11. Preparing for Division
Late Interphase: G2
Prophase
Centromere
Early Spindle Apparatus
Nuclear membrane disappears
Chromosome consisting of two sister chromatids

12. The spindle attaches to the centromeres.
Metaphase
Chromosomes line up at an imaginary line between the centrosomes at opposite ends of the cell.
The spindle attaches to the centromeres.

13. Spindles pull the “daughter” chromosomes appart
Anaphase
Spindles pull the “daughter” chromosomes appart

14. Telophase & Cytokinesis
Two nuclei become visible
In animal cells, a Cleavage Furrow is visible
In plant cells, a cell plate is now visible
Cytokinesis
The cytoplasm and organelles divide.

15. What’s the end product?
Two identical daughter cells ready to start the cycle again… or not.
Some cells (like your nerve and muscle cells) do not undergo division.
For those that do (your skin and the lining of your intestinal tract) how would you know how quickly division takes place?