Describe what happens in each stage of interphase.

G1: - cell grows - organelles, proteins, and ATP are synthesized S: - DNA replicates - each chromosome is copied to form two identical sister chromatids G2: - more protein synthesis - ATP stores increase - DNA is checked and repaired - Cell prepares for mitosis

What is G0 and when does a cell enter it?

- when a cell stops dividing enters when: - differentiated - DNA is damaged

Describe the process of mitosis.

Prophase: - chromosomes condense and become visible - nuclear envelope breaks down - centrioles move to opposite sides of the cell - spindle structures form Metaphase: - chromosomes line up at the equator - spindle fibres attach to chromosomes at the centromere Anaphase: - sister chromatids separate at the centromere - spindle fibres pull each one to opposite sides of the cell, forming two sets of chromosomes Telophase: - chromosomes reached the poles and decondense - nuclear envelope reforms around each set of chromosomes - spindle fibres break down

Describe cytokinesis in animals vs plant cells.

Animal: - cleavage furrow forms around the middle of the cell - membrane pinches in until close enough to fuse around the middle Plants: - vesicles from the Golgi gather at the middle and fuse to form a cell plate which develops into a new cell wall

Describe the process of meiosis.

Prophase I: - chromosomes condense - homologous chromosomes pair up forming bivalents - crossing-over occurs between non-sister chromatids - nuclear envelope breaks down and spindle structures form Metaphase I: - bivalents line up at equator - spindle fibres attach to homologous pairs with random orientation (independent assortment) Anaphase I: - homologous pairs are pulled to opposite sides by spindle fibres - sister chromatids stay together Telophase I: - same as mitosis - two haploid cells are formed Prophase II: - same as mitosis (chromosomes consist of two non-sister chromatids) Metaphase II: - same as mitosis Anaphase II: - same as mitosis Telophase II: - same as mitosis

Describe all of the levels of stem cell potency.

Totipotent: - can differentiate into any type of cell - can produce a whole organism Pluripotent: - any type of cell - can't produce whole organism Multipotent: - can differentiate into a range of cells within a certain type of tissue