bio - cell cycle + mitosis

Interphase

takes abt 3/4 of the cycle (90% of the cell's life)

(Interphase) G1

-cell grows

-protein synthesis occurs

(Interphase) S phase

-DNA synthesis

-as cells age, DNA gets older, and mutations can occur

to go from G1 to S, the cell needs to be...

1) large enough

2) in a suitable environment

(Interphase) G2

mitotic apparatus is produced (microtubules are formed)

Mitotic apparatus

organizes and segregates sister chromatids into two daughter cells

Functions of Mitosis

1) Growth

2) Regeneration

3) Asexual reproduction

Stages of Mitosis (PMAT)

prophase, metaphase, anaphase, telophase

Interphase

-cannot see sister chromatids

-1 nuclear envelope

phrophase

-can start to see sister chromatids

metaphase

-sister chromatids align at the equator of the cell

anaphase

-sister chromatids are split

telophase

-cannot see sister chromatids

-2 nuclear envelopes

prophase (detailed explanation)

1) Nuclear envelope breaks down

2) chromatin condenses into sister chromatids

3) centrioles move from equator to poles of the cell

4) microtubules condense to form spindle fibers

metaphase (detailed explanation)

1) sister chromatids line up at equator of the cell

2) spindle fibers push them to center of the cell

3) kinetochore (where sister meets with the spindle fibers)

4) centromere (sisters are connected here)

metaphase plate

line of sister chromatids

anaphase (detailed explaination)

splitting of sister chromatids into chromosomes (karyokinesis)

telephase

(opposite of prophase steps, there is no order to these events)

1) nuclear envelope reforms around the chromosomes

2) centrioles move toward the equator

3) spindle fibers decondense into individual microtubules

4) chromosomes decondense into chromatin (DNA and proteins)