- Topic 2 Mitosis and Meiosis
- 1 Definitions of cell division, cytokinesis, and karyokinesis
- 2. Brief comparison of mitosis and meiosis
- 3. The cell cycle: interphase (G1, M, G2) and mitosis
- 4. Definitions of haploid, diploid, homologs, homologous
- 5. Mitosis
- A. Prophase
- 1) Definitions of chromatid,
sister-chromatid, centromere, kinetochore,
- spindle fibers,
microtubules, monad, dyad
- 2) Classification of chromosomes by
centromere position
- (metacentric,
sub-metacentric, acrocentric, telocentric)
- B. Metaphase (metaphase plate, microtubules, spindle fibers,
prometaphase)
- C. Anaphase
- 1) Dyads separate into monads
- D. Telophase
- E. Cytokinesis
1) Plants, occurs by formation of a cell plate
2) Animals, occurs by formation of a cell
furrow
- F. Two differences in cell division in plants and animals
- 1) Type of cytokinesis
- 2) Presence of centrioles (present in animals
but not in higher plants)
- G. Summary of mitosis
- 6. Meiosis (converts 2n cells to n gametes or spores)
- A. Reductional division vs. equational division
- B. Meiosis I (reductional division, reduces the chromosome number in
half)
1) Prophase I
- a. Letonema,
homologus chromosomes are unpaired
- b. Zygonema,
homologous chromosomes are pairing
- c. Pachynema,
homologous chromosomes are completely paired (synapsed),
synaptonemal complex
- d. Diplonema and
diakinesis, chromosomes are desynapsing, chiasmata
- 2) Metaphase I, bivalents move to the
metaphase plate
- 3) Anaphase I, homologous chromosomes
separate by reductional division
- 4) Telophase I
- C. Meiosis II
(equational division)
- 1) Prophase II
- 2) Metaphase II
- 3) Anaphase II (equational division)
- 4) Telophase II
7. Comparison of mitosis and meiosis
8. Spermatogenesis and oogenesis in animal cells
9. Advantage of meiosis
10. Asexual vs. sexual reproduction
11. Life cycles in which- A. Mitosis only occurs in haploid cells (example, Chlamydomonas,
yeast)
- B. Mitosis only occurs in diploid cells (example, humans)
- C. Mitosis occurs in both haploid and diploid cells (example, fern)
Updated Aug. 24, 2000
Back to B219 lecture schedule