Mitosis Notes

Cell Cycle

Interphase

● Growth 1 (G1)

– Growth of cell organelles, chromosomes are stretched out and actively giving directions for proteins

● Synthesis (S)

– Chromosomes are replicated and condensed

– Each chromosome consists of two sister chromatids

     connected by a centromere

● Growth 2 (G2)

– Final growth phase, cell makes sure there are enough organelles for each new cell to split

during cytokinesis-GROW & PREPARE FOR MITOSIS

 MITOSIS

Prophase

(This is the OFFICIAL start of “MITOSIS”)

● Chromosomes condense very tightly and are now visible.

● Spindle fibers form

● Nuclear envelope breaks down

Metaphase

● Sister chromatids line up in middle of cell across “equator”

● Centromere attaches to spindle fiber

Anaphase

● Centromere divides

● Spindle fibers pull chromatids apart

● Chromasomes move to opposite sides of cell

Telophase

● Kinda the reverse of Prophase

● Nuclear envelope reforms

● Chromosomes uncoil

● Spindle fibers break down

Cytokinesis

● Separation of the cytoplasm

● Happens during the process of Anaphase and Telophase

● A little bit different in plants than animals

— Plant cells form a cell plate and animal cells form a cleavage burrow between the two cells where they are going to separate.

Result of Mitosis

● Two new cells with identical DNA (cell directions).