08. Meiosis 1

What is a type of cell division in sexually reproducing organisms that reduces the chromosome number in gametes?

Meiosis

What occurs when a diploid cell undergoes two rounds of cell division, resulting in four haploid cells?

Meiosis

What is the chromosome number of the starting cell in meiosis?

Diploid, with two sets of chromosomes, one from each parent

What is the chromosome number of the cells produced by meiosis?

Haploid

How many cells are produced at the end of meiosis?

Four haploid cells

What are the two rounds of cell division in meiosis?

Meiosis I and Meiosis II

Why is meiosis essential for sexual reproduction?

It introduces genetic variation and halves the chromosome number before fertilization

What are the phases of Meiosis I?

Prophase I, Metaphase I, Anaphase I, and Telophase I

What are the phases of Meiosis II?

Prophase II, Metaphase II, Anaphase II, and Telophase II

What happens during Prophase I?

Synapsis, crossing over, and formation of tetrads occur

What happens during Metaphase I?

Tetrads align on the metaphase plate

What happens during Anaphase I?

Homologous chromosomes separate and move toward opposite poles

What happens during Telophase I?

Two haploid daughter cells are formed

What happens during Prophase II?

The spindle apparatus forms and attaches to the chromosomes

What happens during Metaphase II?

Chromosomes align at the metaphase plate

What happens during Anaphase II?

Sister chromatids separate and move to opposite poles

What happens during Telophase II?

Four haploid daughter cells are formed

What separates during Meiosis I?

Homologous chromosomes

What separates during Meiosis II?

Sister chromatids

What is the main result of Meiosis I?

One diploid cell produces two haploid daughter cells

What is the main result of Meiosis II?

Two haploid cells produce four haploid daughter cells