1. MITOSIS and MEIOSIS Two Jobs of DNA
Proteins Synthesis
Self Replication
Mitosis: body cell division: somatic cell division
Meiosis: sex cell division: gamete formation

2. MITOSIS and MEIOSIS A. Prefixes telo end chromo color some body locus
place
homo
same
hetero
different
haplo
half
mono
one di
two
pro
first

3. Why Mitosis?
 Cell Growth

4. A.  Why must cells divide?
larger
1. The ____________a cell becomes, the more demands the cell places on its ________ In addition, the cell has more trouble moving enough ________and __________ across the cell membrane.
DNA
wastes
nutrients
The rate at which food, oxygen and water are used and waste is produced depends on the cell’s ________________.
volume
The rate at which food, oxygen, water, and wastes are moved in and out of the cell is dependent on the ___________________ of the cell.
surface area

5. Ratio of Surface Area to Volume
As the length of a cell increases, its volume increases __________ than the surface area.
The decrease in the cell’s ratio of surface area to volume makes it more __________ for the cell to move needed materials in and waste products out quickly enough for the cell to survive.
faster
difficult

6. Division of the Cell
Before it becomes too large, a growing cell divides forming two _______________ cells.
The process by which a cell divides into two new daughter cells is called cell division or __________________.
daughter
MITOSIS
In some eukaryotic one celled organisms this mode of division is called ___________________ reproduction because the genetic information remains constant from one cell cycle to another
asexual
Prefix “a” means:
not or no

7. CANCER What happens when cell growth becomes unregulated?
What are some forms of cancer?
SKIN CANCER VIDEO

8. MITOSIS A. General information 1. Definition: Somatic cell division
2. Nickname: “Normal” cell division
B. Background Information
1. Pairs of shoes?
a. chromosomes are like shoes they come in pairs
b. this is called the diploid condition
c. this is designated 2n
d. What would the n condition be called?

9. MEIOSIS A. General information 1. Definition: formation of sex cells
2. Nickname: “reduction” cell division
3. Starting cell: germ cell
4. Start with one cell : end with 4 “cells”

10. Homologous chromosomes
MITOSIS
Same: eyes
Different: hair, nose and ears
B. Background Information
1. Homologous Chromosomes
b. the chromosomes to the right are homologues, they control like traits (hair/eye color, nose shape, ear lobes), but the control can be the same or different
Homologous chromosomes
a. def: chromosomes that control the same traits but not necessarily in the same way
Question: which traits are controlled the same? Which differently?
Punch here for answer

11. Sister chromatids attached by a centromere
MITOSIS
C. Jobs of DNA: Replication and Protein Synthesis
1. Prior to cell division DNA replicates itself. Each chromosome forms a mirror image of itself called a sister chromatid
Sister chromatids attached by a centromere
Question: If the chromosome on the right replicates itself what will it look like. Draw a picture in your notes
Click here for answer

12. Lets go to the video tape
THE MITOSIS ZONE
Lets go to the video tape

13. MITOSIS
INTERPHASE
EVENTS:
CELL IS AT REST

14. EARLY PROPHASE EVENTS IN EARLY PROPHASE
1. Nuclear membrane begins to disappear
Nuclear membrane
nucleolus
centrioles
Question: Don’t go until you can identify homologues and chromatids
2. Nucleolus disappears
3.Chromatin duplicates
4. Chromatin shortens and thickens
5. Centrioles duplicate and migrate

15. Late Prophase Events during late prophase 1. Aster rays appear
2. Spindle fibers appear

16. Metaphase Events of metaphase 1. Chromosomes line up on cell equator
2.. Homologous chromosomes are present but they do not pair (match) up.
Metaphase

17. Anaphase Events of anaphase 1. Chromosomes begin to migrate to poles
2/4/2019
Events of anaphase
1. Chromosomes begin to migrate to poles

18. Telophase Events of telophase 7. Partition forms two new cells
a. plants: plate/cell wall
Events of telophase
b. animals: membrane pinches off
1. Chromosomes lengthen and thin become chromatin
2. Aster rays disappear
3. Spindle fibers disappear
4. Nuclear membrane reforms
5. Nucleolus reforms
6. Centrioles reform

19. Interphase
Cell is at rest
Two identical cells

20. Onion Cell Mitosis

21. Specialized diploid cell found in the ovaries and testes
Meiosis
Interphase
Germ Cell
Specialized diploid cell found in the ovaries and testes

22. Meiosis Early Prophase Events 1. Chromosomes condense
2. Chromosomes duplicate
3. Nuclear membrane disappearing
4. Nucleolus disappearing
5. Centrioles migrate

23. Meiosis Late Prophase I Events 1. Aster rays appear
2. Spindle fibers appear

24. Meiosis
Metaphase I
Events