AP Bio - Cell Cycle

Phases of interphase

G0, G1, S, G2

G0

A cell is not reproducing or preparing to reproduce

G1

Replication of organelles, cell growth

S

DNA replication

G2

Cell continues growth, last minute proteins for mitosis

Mitosis

Nuclear division, four stages

Prophase

Stage of mitosis: Nucleus dissolves

Metaphase

Stage of mitosis: Chromosomes lined up down the middle of the cell with spindle fibers

Anaphase

Stage of mitosis: spindle fibers pull chromosomes away, cell begins separation

Telaphase

Stage of mitosis: cytoplasm separates

Cytokinesis

Cytoplasm division from mother cell to two daughter cells

Plant; animal

Cell wall in cytokinesis; cleavage furrow in cytokinesis

Chromosome

A piece of DNA, either separate or connected to another by a centromere

Chromotid

When chromosomes are bound together by a centromere, this is one of the chromosomes

Chromatin

Unraveled chromosomes before mitosis

Spindle fibers

Micro tubules made of protein that help transport things around the cell

G1 checkpoint

Checkpoint for initial DNA damage

G2 checkpoint

Checkpoint for DNA replication and cell size

M checkpoint

Occurs during metaphase, checks to see if spindle fibers properly attach to the chromosomes

Cyclins

Proteins produced to promote cell cycle progression

Kinases

Activated by cyclins, proteins that regulate the cell cycle

How a cell moves to the next stage

Kinases will be activated in high enough numbers by cyclins, cell proceeds to the next stage

Cancer

Uncontrolled cell division, often with a genetic defect

Apoptosis

Cell death, occurs when a defect cannot be fixed

Centromere

Connecting two chromosomes in the middle

Diploid cells

46 chromosomes (1 pair of each), body/somatic cells

Haploid cell

23 chromosomes (1 of each), egg/sperm cells

90%

Amount of time a cell spends in interphase