Understanding meiosis is very important. There are several steps and it is an important process in the production of gametes.
Start studying mieosis here:
http://www.cellsalive.com/meiosis.htm
Events during Meiosis
Identify all of the steps as you watch the video:
Diploid Cell (2N): From a preceding mitotic division, the Oogonium (Spermatogonium) enters meiosis with DIPLOID (2N) chromosomes but TETRAPLOID (4N) DNA. Chromosomes then duplicate to produce SISTER CHROMATIDS (or HOMOLOGOUS DYADS).
Prophase I: Dyad pairs align to create "TETRADS", non-sister chromatids connect and trade sections at a "CHIASMA", a process called "CROSSING OVER".
Metaphase I: SPINDLE FIBERS attach to each dyad at the KINETOCHORE. Tension from spindle fibers aligns the tetrads at the cell equator.
Anaphase I: Chiasmata break apart and sister chromatids begin migrating toward opposite poles.
Telophase I: CLEAVAGE FURROW forms beginning the process of CYTOKINESIS (cell division). Resulting daughter cells are HAPLOID (1N).
Prophase II: Spindle formation begins and centrosomes begin moving toward poles.
Metaphase II: Tension from spindle fibers aligns chromosomes at the metaphase plate.
Anaphase II: CHROMATIDS separate and begin moving to the poles.
Telophase II: CLEAVAGE FURROW forms beginning CYTOKINESIS.
Gamete (1N): NUCLEAR ENVELOPES form and chromosomes disperse as CHROMATIN. Meiosis has produced 4 DAUGHTER CELLS, each with 1N chromosomes and 1N DNA. Later, in fertilization, male and female 1N gametes will fuse to form a 2N ZYGOTE.
http://www.emc.maricopa.edu/faculty/farabee/biobk/biobookmeiosis.html
Identify diploid and haploid and what it means.
Follow down to the stages of meiosis and watch how each step changes.
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