Question

1: Describe the two main phases of the cell cycle.

2: what must happen before mitosis can begin.

3: what is produced by mitosis?

4: what are the four steps of mitosis in order?

5: how does meiosis genetic variation into offspring?

6: how do the products of meiosis compare to the original cell?

7: why are there two sets of phases during meiosis, but only one during mitosis?

8:A plant can have either tall (T) stems or (t) stems. Two plants are crossed. One has the genotype Tt and the other has the genotype Tt. fill in the Punnett square below for this cross.

9: what is the genotype ratio for this cross?

10: what is the phenotype ratio for this cross?

PLEASE HELP ME THIS IS IMPORTANT!!!

Answer 1

1)The cell cycle has two major phases: interphase and the mitotic phase During interphase, the cell grows and DNA is replicated. During the mitotic phase, the replicated DNA and cytoplasmic contents are separated, and the cell divides.

2) Before mitosis can begin, the chromosomes, or genetic material, must be copied, which occurs during interphase.

3) Mitosis produces new cells, and replaces cells that are old, lost or damaged.

4) prophase, metaphase, anaphase, and telophase (MIGHT'VE MISPELT!!)

5) In Prophase I of Meiosis I, homologous chromosomes line up their chromatids and "cross-over", or exchange corresponding segments of DNA with each other. This produces genetic variation by allowing more combinations of genes to be produced

6) eiosis results in four haploid genetically unique daughter cells, each with half the DNA of the parent cell. in human cells, the parent cell has 46 chromosomes (23 pairs), so the cells produced by meiosis have 23 chromosomes. These cells will become gametes. (not sure if I answered u, sorry!!)

7) Cells undergoing mitosis just divide once because they are forming two new genetically identical cells where as in meiosis cells require two sets of divisions because they need to make the cell a haploid cell which only has half of the total number of chromosomes.