Understanding the Cell Cycle: Stages of Cell Growth and Division
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The cell cycle is a vital process through which a cell grows, prepares for division, and ultimately divides into two daughter cells. It comprises three main stages: Interphase, where the cell grows and duplicates its DNA; Mitosis, which encompasses four phases (Prophase, Metaphase, Anaphase, and Telophase) that involve the division of the nucleus; and Cytokinesis, where the cell membrane pinches off, resulting in two distinct daughter cells. This cycle is essential for growth, development, and tissue repair in living organisms.
Understanding the Cell Cycle: Stages of Cell Growth and Division
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Presentation Transcript
Section 4-3 Cell Division
The Cell Cycle • During the cell cycle a cell grows, prepares for division, and divides into two “daughter cells”
Stage 1: Interphase • The cell grows, duplicates organelles, and makes a copy of DNA. • The cell’s nucleus is uniform and the cell is regularly shaped • It just looks like a cell…
Stage 2: Mitosis • The nucleus of the cell divides into two new nuclei • Mitosis has 4 stages • By looking at the nucleus and chromosomes you can determine what stage of mitosis the cell is in.
Mitosis 1: Prophase • During prophase the chromatin (bundles of DNA) condense into two-rod structures called chromosomes, which makes the nucleus look chunky • There are two rods in chromosomes because DNA has been duplicated.
Mitosis 2: Metaphase • During metaphase the chromosomes line up down the middle of the cell. • They are attached to the centrioles by spindle fibers (used to be the cytoskeleton). Centromere Spindle Fibers
Mitosis 3: Anaphase • During anaphase the chromosomes are torn apart at the centromeres and move toward opposite ends of the cell.
Mitosis 4: Telophase • During telophase the chromosomes begin to lose their rod-shape and a new nucleus starts to form around them.
Stage 3: Cytokinesis • The cell membrane pinches off and the cell splits in two. • Called daughter cells • The new cells are now in interphase and the cycle starts again.