1. 5.1 The Cell Cycle KEY CONCEPT Cells come from preexisting cells Cell Reproduction

2. 5.1 The Cell Cycle All Cells Come From Cells Why do organisms need cellular reproduction to occur? Cell Reproduction 1. Enables organisms to grow 2. Enables organisms to repair damaged cells 3. Allows organisms to reproduce by producing gametes (sex cells)

3. 5.1 The Cell Cycle 2 Types of Reproduction 1. Asexual Reproduction Cell Reproduction - 1 parent - No gametes (no sex cells) - Offspring are genetically identical to parent Examples: Binary fission Budding Vegetative Propagation Spores

4. 5.1 The Cell Cycle Binary fission When a unicellular organism makes a copy of its genetic material and then splits into 2 cells.

5. 5.1 The Cell Cycle Budding When an offspring grows off the parent then breaks off. –Ex) Hydra Saccharomyces cerevisiae

6. 5.1 The Cell Cycle Vegetative Propagation –It is a process by which new individuals arise without production of seeds or spores. -Shoots, Rhizomes (runners) are examples.

7. 5.1 The Cell Cycle

8. Spores An asexual cell that grows into a new offspring. –Ex) Ferns, Mosses, Mushrooms, Molds

9. 5.1 The Cell Cycle Sexual Reproduction Cell Reproduction 2 Types of reproduction - 2 Parents -Gametes required (egg and sperm) -Genetic material from each of two parents combines -Producing offspring that are genetically different then the parents - Requires Meiosis: the process by which gametes are made

10. 5.1 The Cell Cycle New Cells are made During the Cell Cycle This process includes 2 parts… Cell Reproduction The Cell Cycle with mitosis 1. Interphase: Stage when the cell grows and makes a copy of DNA (DNA replication) AND… 2. Mitosis: For the creation of somatic cells and asexual reproduction OR Meiosis: For the creation of gametes): are the division of the nucleus

11. 5.1 The Cell Cycle Cells divide at different rates. The rate of cell division varies with the need for those types of cells. Some cells are unlikely to divide (G 0 ) like Brain Cells. Cell Reproduction

12. 5.1 The Cell Cycle Interphase: Includes G1, S, and G2 phases –Gap 1 (G 1 ): cell growth and normal functions – Synthesis (S): DNA is copied –Gap 2 (G 2 ): additional growth The Cell Cycle

13. 5.1 The Cell Cycle Mitosis Mitosis only occurs if the cell is big enough and the DNA is not damaged Mitosis (M): includes division of the cell nucleus (mitosis) and division of the cell cytoplasm (cytokinesis) Includes P.M.A.T. –Prophase –Metaphase –Anaphase –Telophase The Cell Cycle

14. 5.1 The Cell Cycle Cell size is limited. Volume increases faster than surface area. Cell Reproduction

15. 5.1 The Cell Cycle Surface area must allow for adequate exchange of materials. –Cell growth is coordinated with division. –Cells that must be large have unique shapes. Cell Reproduction