BIOLOGY 1A03 Lecture Notes - Lecture 15: Cytokinesis, Cleavage Furrow, Telophase

• School: McMaster University
• Department: Biology
• Course: BIOLOGY 1A03
• Professor: Lovaye Kajiura

Document Summary

The beginning of the m-stage of the cell cycle follows up on the end of the interphase. During interphase, speci c chromosomes cannot be identi ed since they are organized into the long chromatin bers. However as a cell transitions from g2 to the m-phase, the duplicated chromosomes begin to condense and the individual chromosomes become visible even with a light microscope. During prophase, each chromosome will appear as identical sister chromatids that are joined at their centromeres. At the same time, duplicated cellular microtubule organizing centres referred to as the centrosomes, begin to radiate long microtubules, forming a mitotic spindle. The centrosomes will become positioned at opposite poles of the cell, and the mitotic spindle will become crucial for separating the chromosomes into the two daughter cells. The de ning feature of prometaphase is the fragmentation of the nuclear envelope.