Mitosis

Question 1

Why is mitosis needed?

Answer 1

• For the growth of multicellular organisms.

• For repairing damaged tissues.

Question 2

Fill in the blank about prophase in mitosis (1st stage):

The chromosomes ________. The __________ move to the opposite ends of the cell, forming the _______. The nuclear envelope breaks down.

Answer 2

• The chromosomes (condense). The (centrioles) move to the opposite ends of the cell, forming the (spindle). The nuclear envelope breaks down.

Question 3

Fill in the blank about metaphase in mitosis (2nd stage):

The chromosomes attach to the _______ by their __________ and line up along the middle of the cell.

Answer 3

The chromosomes attach to the (spindle) by their (centromere) and line up along the middle of the cell.

Question 4

Fill in the blank about anaphase in mitosis (3rd stage):

The centromeres divide, __________ each pair of sister __________. The spindles contract, pulling chromatids to opposite ends of the cell, centromere first.

Answer 4

The centromeres divide, (separating) each pair of sister (chromatids). The spindles contract, pulling chromatids to opposite ends of the cell, centromere first.

Question 5

Fill in the blank about telophase in mitosis (4th stage):

The chromatids reach the opposite _____. They ______ and become long and thin again. They’re now called chromosomes again. A _______ ________ forms around each group of chromosomes, so there are now two nuclei.

Answer 5

The chromatids reach the opposite (poles). They (uncoil) and become long and thin again. They’re now called chromosomes again. A (nuclear) (envelope) forms around each group of chromosomes, so there are now two nuclei.

Question 6

Fill in the blank about cytokinesis in M phase:

The cytoplasm _______. In animal cells, a ________ ______ forms to divide the cell membrane. There are now two daughter cells that are genetically _________ to the original and to each other. Cytokinesis usually begins in ________ and ends in telophase. It’s a separate process to mitosis.

Answer 6

The cytoplasm (divides). In animal cells, a (cleavage) (furrow) forms to divide the cell membrane. There are now two daughter cells that are genetically (identical) to the original and to each other. Cytokinesis usually begins in (anaphase) and ends in telophase. It’s a separate process to mitosis.