PHASES OF MITOSIS

Reviewer ni sir lance

PROPHASE

The phase where the cytoplasm divides, creating two separate daughter cells.

PROMETAPHASE

Condensed chromosomes attached to the spindle by their kinetochores. Each sister chromatid’s kinetochore attaches to microtubules from opposite poles.

METAPHASE

All chromosomes align at the cell’s equator, forming the metaphase plate. Sister chromatids are held under tension and oriented toward opposite poles.

ANAPHASE

Shortest and most dramatic phase. Cohesin proteins holding sister chromatids together at the centromere are degraded. Freed sister chromatids (now individual chromosomes) are pulled rapidly toward opposite poles. Poles also move farther apart.

TELOPHASE

The spindle apparatus disassembles. Nuclear envelopes re-form around each set of new chromosomes. Chromosomes uncoil, and the nucleolus reappears.

IN ANIMAL CELLS

a cleavage furrow forms as a constricting belt of actin filaments slides past one another, pinching the cell into two.

CELL PLATE

a rigid cell wall prevents pinching. Vesicles assemble membrane components to form an expanding membrane partition called the ______.