Mitotic Cell Cycle

Binary Fission

Mitotic Cell Cycle

Interphase

• DNA replicates during S period.

Replication: The difference between homologous chromosomes and sister chromatids

Phases of Mitosis

Prophase

• Chromosomes coil, condense, shorten, and become visible.

• Spindle forms.

Prometaphase

• Nuclear envelope disappears.

• Nucleolus disappears too.

Metaphase

• The spindle microtubules align the chromosomes in the middle of the spindle.

Anaphase

• The centromeres divide and the microtubules pull the chromatids apart toward opposite poles.

Early Telophase

• The chromosome arrive at opposite poles, uncoil and elongate.

• Spindle disappears.

Late Telophase

• Nuclear membrane forms around each set of chromosomes.

• Nucleolus reappears.

The Resulting Daughter Cells

• Are genetically identical, each with the same chromosome number as the parent cell.

Cytokinesis in Animal Cells:occurs by actin

filaments pinching the cell in two

Cytokinesis in Plant Cells: a new cell wall is laid down to divide the two daughter cells

Question 1

• In mitosis, if a parent cell has 24 chromosomes, each daughter cell will have how many chromosomes?

• A. 48

• B. 72

• C. 12

• D. 24

• E. 6

Question 2

• What happens during anaphase of mitosis?

• A. chromosomes condense.

• B. chromosomes align on the cell equator.

• C. chromosomes are pulled apart by spindle fibers.

• D. cells split in two.

• E. none of the above.

Question 3

• Chromosomes are duplicated during which period?

• A. metaphase.

• B. G1 period.

• C. S period.

• D. anaphase.

• E. G2 period.

Answers

• Question 1: D

• Question 2: C

• Question 3: C