Cell Reproduction

New cells are produced from one preexisting cell Forms two cells identical to the original cell Chromosomes – compacted chromatin that becomes tightly packed before cell division Carries genetic material that is copied and passed from generation to generation.

The Cell Cycle

Interphase 1. G1 Phase 2. S Phase Cell grows and develops. Chromosomes are replicated; divide to form identical sister chromatids connected by a centromere.

3. G2 Phase Interphase cont. Make proteins for mitosis Cell organizes and prepares for cell division. Centriole pair replicates and prepares to form the spindle fibers.

Mitosis Process by which 2 daughter cells are formed. Cell spends most of its time in Interphase (G1, S, G2)

1. Prophase Chromatin coils up into visible chromosomes Nucleus disappears Centrioles move to opposite ends of the cell Spindle fibers begin to form between the centrioles

Prophase cont.

Prophase cont.

2. Metaphase Chromosomes become attached to the spindle fibers. Chromosomes line up in the middle of the spindle fibers.

Metaphase cont.

3. Anaphase Centromeres split apart Chromatid pairs from each chromosome separate Shortening of spindle fibers pulls chromatids apart.

Anaphase Cont.

4. Telophase (Prophase Reversed) Begins when chromatids reach the opposite poles Chromosomes unwind Spindle breaks down New nuclei form in each new cell.

Telophase cont.

Telophase cont.