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rd File Edit View Insert Format Tools Table Window Help AutoSaver @ S E D 213 Cell Division Meiosis Online Lab Q me Insert Draw Design Layout References Mailings Review > Share Comme Times New... 11 A A Aa AO E E ES ster в I vab x x Av AL Styles Styles Pane 5. If a parental cell has 46 chromosomes, how many chromosomes does each daughter cell have after mitosis (and cytokinesis)? How many daughter cells are produced? 6. If a parental cell has 46 chromosomes, how many chromosomes does each daughter cell have after meiosis (and cytokinesis)? How many daughter cells are produced? 7. Which organs (be specific) in the human body produce cells by meiosis? 8. Chromosomes that look alike and carry the same genes are called 9. Name and describe the two processes which are responsible for the genetic variety seen in cells produced by meiosis. 10. Why are the gametes (egg and sperm) in sexually reproducing species produced by meiosis instead of by mitosis? Provide at least two reasons. Page 2 of 5 686 words Focus - MacBook Air

Answer 1

5. Mitosis produces two identical daughter cells. If the parental cell has 46 chromosomes the daughter each daughter cell will have 46 chromosomes after mitosis.

6. Meiosis produces four haploid daughter cells. Each daughter cell will have half the number of chromosomes of the parent cell i.e, each daughter cell will have 23 chromosomes.

7. In human body, meiosis take place in the organ-  testis (produce sperm cell) in male and ovary (produce egg cell) in female.

8. Homologous chromosomes.

9. Crossing over and Independant assortment are the two processes responsible for genetic variety in meiosis. During prophase of meiosis 1, the double chromatid homologous pair of chromosomes cross over with each other and exchange chromosome segments. It allows genes from each parent to intermix. In independant assortment, the alleles of two different genes get sorted into gametes independantly of one another.

10. During reproduction, when the sperm and egg unite to form a single cell, the number of chromosomes is restored in the offspring. Meiosis begins with a parental cell that is diploid. The parental cell undergoes one round of DNA replication followed by two seperate cycles of nuclear division. This results in four daughter cells that are haploid. The chromosomes recieved from parents get shuffled in meiosis during crossing over and the offspring will not possess same chromosomes as its parents’. Also meiosis involves independant assortment that results in genetic diversity. With 23 chromosomes assorting independantly, there are 223 or 8 million possible assortment of chromosomes inherited for every cell. These are not possible in mitosis. This is the reason why gametes in sexually reproducing species are produced by meiosis instead of mitosis.