1. The Cell Cycle

2. POINT > Describe three reasons cells divide
POINT > Identify the three parts of the cell cycle
POINT > Identify three stages of interphase
POINT > Identify four stages of mitosis
POINT > Describe how cytokinesis is different in plant and animal cells

3. POINT > Describe three reasons cells divide
20 µm
100 µm
200 µm
(1) Reproduction Unicellular organisms divide as a way to reproduce
(2) Growth and development. The cells of multicellular organisms divide for growth
(3) Tissue repair. Damaged or old cells need to be replaced

4. POINT > Describe three reasons cells divide
20 µm
100 µm
200 µm
(1)Reproduction Unicellular organisms divide as a way to reproduce
(2) Growth and development The cells of multicellular organisms divide for growth
(3) Tissue repair. Damaged or old cells need to be replaced

5. POINT > Describe three reasons cells divide
20 µm
100 µm
200 µm
(1) Reproduction Unicellular organisms divide as a way to reproduce
(2) Growth and development The cells of multicellular organisms divide for growth
(3) Tissue repair Damaged or old cells need to be replaced

6. CHECK:
What are 3 reasons cells must divide?
What is produced during cell respiration?
What are the products of photosynthesis?
What are the reactants of cell respiration?
What is a eukaryote?
What are stomata?
What is osmosis?

7. POINT > Identify 3 parts of the cell cycle
The cell cycle consists of
1) Interphase – normal cell activity
2) Mitosis– the nucleus divides into two
3) Cytokinesis – the cell divides into two new cells
Growth
G 1
(DNA synthesis)
Growth G2
Cell Divsion

8. POINT > Identify three stages of interphase
Cells spend most of the cell cycle in interphase
The purpose of interphase is for cell growth and DNA replication
By the end of interphase a cell has two sets of DNA (chromosomes) and is large enough to divide

9. POINT > Identify three stages of interphase
Interphase is divided into three phases
1. G1 (Gap 1) phase: the cell grows and makes more proteins and organelles

10. POINT > Identify three stages of interphase
Interphase is divided into three phases
2. S (Synthesis) phase the DNA replicates, so both “daughter” cells will receive a full copy of the DNA

11. POINT > Identify three stages of interphase
Interphase is divided into three phases
3. G2 (Gap 2) phase, cells continue to grow and produce the proteins necessary for cell division

12. CHECK:
What happens during the S phase of interphase?
What are the 3 parts of interphase?
What happens during G1 phase?
What do ribosomes do?
What is a eukaryote?
What is active transport?

13. POINT > Identify the four phases of mitosis
Mitosis is the division of the nucleus
Mitosis is divided into four phases. Each phase is characterized by specific processes involving different structures
Prophase
Metaphase
Anaphase
Telophase

14. POINT > Identify the four phases of mitosis
1. Prophase: ) DNA wraps up tightly with proteins to form chromosomes
2) The nuclear membrane disappears
DNA during interphase
DNA during mitosis
DNA double helix
DNA and histones
Chromatin
Supercoiled DNA

15. POINT > Describe the structure of chromosomes
The DNA was replicated during S-phase of interphase.
During prophase it condenses into chromosomes
The two copies of the DNA are called sister chromatids
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Metaphase chromosome
Kinetochore
microtubules
Centromere
region of
chromosome
Sister Chromatids

16. CHECK:
What are the 4 phases of mitosis?
What are 2 things that happen in prophase?
What is an autotroph?

17. POINT > Identify the four phases of mitosis
2. Metaphase: chromosomes line up in the middle of the cell

18. POINT > Identify the four phases of mitosis
3. Anaphase: sister chromatids separate to opposite sides of the cell

19. POINT > Identify the four phases of mitosis
4. Telophase: the new nuclei form and chromosomes begin to uncoil

20. CHECK:
What happens during metaphase?
What happens during anaphase?
What happens during telophase?
What are the two types of fermentation?
What is produced during alcoholic fermentation?
What types of cells use lactic acid fermentation?

21. POINT > Describe how cytokinesis is different in plant and animal cells
Cytokinesis is the physical division of the cell into two “daughter” cells
Cytokinesis is different in plant and animal cells

22. POINT > Describe how cytokinesis is different in plant and animal cells
In animal cells the cell membrane pinches in half to create two new cells

23. POINT > Describe how cytokinesis is different in plant and animal cells
In plant cells a cell plate grows between the two new daughter cells. This makes a new cell wall

24. POINT > Review the basics of the cell cycle
Mitosis results in two genetically identical daughter cells

25. CHECK:
What is cytokinesis?
How many cells are produced by mitosis?
What happens during cytokinesis in plant cells?
What are the subunits proteins are made of?
What are the 3 Domains of living things?

26. Homework:
Complete Study Guide
Read pages
S.A. page 100 #1a-c
GRAS pp #1-11