Mrs. Paparella February 4, 2014 Mitosis vs Meiosis Mrs. Paparella February 4, 2014

Mitosis Cell division which makes an exact copy of the chromosomes and then the one cell becomes 2 cells. (2 daughter cells) Needed for organism growth and tissue repair Method of asexual reproduction in plants and bacteria

Meiosis Cell division which occurs in 2 rounds and ends up making 4 cells which have ½ the number of original chromosomes. Occurs only in the gonads of sexually reproducing organisms to make the gametes. Ovaries(gonad) make the eggs (gametes) through meiosis. Testes(gonads) make the sperm(gametes) through meiosis.

Why isn’t interphase shown here as a phase of mitosis? Remember that interphase is really not part of mitosis. Interphase is the growth/resting period of the cell. Most cells are going to be in interphase and not actually dividing.

1. Please identify this phase of mitosis Interphase Prophase Metaphase Anaphase Telophase

2. Identify the phase of mitosis seen here. Interphase Prophase Metaphase Anaphase Telophase

3. Which phase of mitosis is seen here? Interphase Prophase Metaphase Anaphase Telophase

4. Which phase of mitosis is seen here?

Cytokinesis 5. When does cytokinesis occur?

Paramecium undergoing binary fission, a type of mitosis (asexual reproduction) <<This is a hydra reproducing by the asexual method called “budding”.

http://youtu.be/zrx7Xg0gkQ4

Meiosis Notice that there are pieces of the different chromosomes in the daughter cells. The 4 cells produced are not identical.

6. What is the difference between the terms haploid and diploid?

7. What phase of meiosis has the exchange of genetic material through crossing over?

8. Which process is used for tissue repair?

9. Does this diagram represent mitosis or meiosis? 10. How many pairs of chromosomes do humans have according to the diagram above?

11. What process made these sperm and egg? Ovum is the scientific name for the female egg. Notice that the male actually makes 4 sperm, but the female makes 1 egg and 3 polar bodies which are not functional. 11. What process made these sperm and egg?