Meiosis Flashcards

Study Notes

Meiosis Overview

Meiosis is a specialized cell division that halves the chromosome number.
It occurs in two stages: meiosis I and meiosis II.

Meiosis I

Prophase I: Chromosomes become visible as paired chromatids; the nuclear envelope disappears; includes reduction division.
Metaphase I: Chromosomes attach to spindle fibers and align at the metaphase plate.
Anaphase I: Homologous chromosomes move to opposite poles of the spindle.
Telophase I: Chromosomes reach the poles, and two nuclei form, followed by cytokinesis which results in two daughter cells.
Result: Each daughter cell has one set of chromosomes, thus reducing ploidy.

Meiosis II

Prophase II: Nuclear envelope breaks down; spindle apparatus forms.
Metaphase II: Chromosomes align on the metaphase plate, attached to fully formed spindle fibers.
Anaphase II: Centromeres separate; sister chromatids move to opposite poles.
Telophase II: Nuclear envelopes form around each set of chromosomes; cytokinesis results in four daughter cells.
Result: Four haploid daughter cells, each containing a single chromosome set.

Key Differences Between Meiosis I and Meiosis II

Meiosis I separates homologous chromosomes, resulting in reduced ploidy.
Meiosis II separates sister chromatids, maintaining the haploid condition.

Meiosis Result

One parent cell undergoes two divisions to create four haploid daughter cells.
Meiosis produces sex cells or gametes: eggs in females and sperm in males.

Sex Chromosomes

Female: XX
Male: XY

Description

Test your knowledge with these flashcards on meiosis, covering key terms and stages of this essential cell division process. From the definition of meiosis to the specifics of prophase and metaphase, these cards provide a quick review for students learning about cellular reproduction.