Presentation on theme: "How do baby animals grow to be adults?. Why do animals shed their skin?"— Presentation transcript:
How do baby animals grow to be adults?
Why do animals shed their skin?
Cells divide for three purposes: Growth of the organism Repair damaged structures Asexual reproduction
The Cell Cycle - Mitosis A cell grows, prepares for division, and then divides into two new cells. These two new cells, called daughter cells, are identical to the parent cell because they have the same DNA as the parent cell.
3 stages of the Cell Cycle: Interphase Mitosis –P–Prophase –M–Metaphase –A–Anaphase –T–Telophase Cytokinesis
Interphase Cell spends most of its life in this phase The cell grows to its full size DNA is copied in the nucleus of the cell Cell prepares to divide
Prophase 1 st and longest phase of Mitosis Chromosomes become visible Centrioles separate and move to opposite ends of cell Spindle fibers appear Nuclear membrane disappears
Metaphase 2 nd and shortest phase of Mitosis Chromosomes attach to spindle fibers in center of cell
Anaphase 3 rd phase of Mitosis Centromeres split apart and chromatids separate from each other. Chromosomes move to opposite poles
Telophase 4 th and last phase of Mitosis Chromosomes reach opposite poles of cell Chromatids unwind back into chromatin Nuclear membranes begins to form around the chromatin at each end Spindle fibers disappear
Cytokinesis New cell membrane forms between two nuclei. The cell splits into two new cells – each with identical chromosomes.