Meiosis

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Interphase: DNA replicates ( S-phase)

Prophase: Nucleolus fades and chromatin (replicated DNA and associated proteins) condenses into chromosomes. Each replicated chromosome comprises two chromatids, both with the same genetic information. Microtubules of the cytoskeleton, responsible for cell shape, motility and attachment to other cells during interphase, disassemble

Pro Metaphase: - nuclear envelope breaks down- no longer a recognizable nucleus. Mitotic spindle fibers elongate from the centrosomes and attach to kinetochores, protein bundles at the centromere region on the chromosomes where sister chromatids are joined Metaphase: Tension applied by the spindle fibers aligns all chromosomes in one plane at the center of the cell.

Anaphase: Spindle fibers shorten, the kinetochores separate, and the chromatids (daughter chromosomes) are pulled apart and begin moving to the cell poles (centrioles- located on opposite sides of the cell).

Telophase: Nuclear membrane and nucleolus begin to reform (one at each end=2). Spindle fibers begin to disappear. Chromosomes uncoil; start to go back to being chromatin. Cytokinesis: 2 cells split along the cleavage furrow

Nucleolus: contains all of the DNA (chromatin) of a cell
Nuclear membrane: phospholipid bi-layer, protects nucleus?
Chromosome: Threadlike structure of DNA/RNA (gene codes), we have two copies of every chromosome Chromatin: chromosomes are made of chromatin

Sister Chromatids: the two identical halves of a chromsome

Chiasma: during prophase the chromsomes sometimes “crossover” (exchange genetic material)= chiasma

Tetrad/Bivalent: group of four chromatids, bivalent=pair
Synapsis: The pairing of homologous chromosomes during the meiotic phase of cell division/The act of lining up side by side by homologous chromosomes during the meiotic phase of cell division. ( forms chiasmas?) Haploid/diploid: Haploid= cell containg half the number of chromsosomes Diploid= cell containing twice as many...
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