Cell Division – a review
Cell Cycle Control: What happens at each checkpoint? M = mitosis (nuclear division) C = cytokinesis (cytoplasmic division) G = gap (cell growth) S = synthesis (DNA replicated, cell growth)
When to Divide?
Growth Inhibition
Control Problems - Cancer
Supercoiling (DNA coils forming a chromatid)
Human Chromosomes (unreplicated)
Human Chromosomes (replicated and supercoiled)
Chromosome (replicated)
Chromosome Each DNA molecule coils to form a single chromatid. The two chromatids of a replicated chromosome are genetically identical.
The Cell Cycle (Overview)
Mitosis - Stages
Prophase and Metaphase
Anaphase and Telophase
Cytokinesis (animal and plant)
MEIOSIS the other type of nuclear division
Gametes… why haploid?
Oogenesis
Spermatogenesis
Meiosis
Meiosis Overview
Meiosis (Part I)
Meiosis (Part II)
Independent Assortment of Chromosomes
Independent Assortment another view
What happens when chromosomes do not separate properly during meiosis? Nondisjunction
Down’s Syndrome trisomy 23
Crossing Over Leads to Genetic Variability
Compare Mitosis and Meiosis
Mitosis vs. Meiosis