10.1 Meiosis

Question 1

What happens in interphase?

Answer 1

Gap 1, Synthesis, Gap 2.
Gap 1: cell grows in size, checks for DNA damage
Synthesis: DNA replicated, results in chromosomes with identical DNA strands (sister chromatids held together by central region, centromere)
Gap 2: cell again grows in size for meiosis I

Question 2

What happens in prophase I?

Answer 2

Chromosomes condense, nuclear membrane dissolves, homologous chromosomes form bivalents, crossing over occurs

Question 3

What happens in metaphase I?

Answer 3

Spindle fibres from opposing centrosomes connect to bivalents at centromeres, aligns along middle of cell

Question 4

What happens in anaphase I?

Answer 4

Spindle fibres contract and splits bivalent, homologous chromosomes move to opposite poles of cell

Question 5

What happens in telophase I?

Answer 5

Chromosomes decondense, nuclear membrane reforms

Question 6

What happens in cytokinesis?

Answer 6

Cells divide to form two haploid daughter cells (meiosis I), cells divide to form four haploid daughter cells (meiosis II)

Question 7

What happens in prophase II?

Answer 7

Chromosomes condense, nuclear membrane dissolves, centrosomes move to opposite poles perpendicular to meiosis I

Question 8

What happens in metaphase II?

Answer 8

Spindle fibres from opposing centrosomes attach to chromosomes at centromere, aligns along cell equator

Question 9

What happens in anaphase II?

Answer 9

Spindle fibres contract and separate sister chromatids which move to opposite poles

Question 10

What happens in telophase II?

Answer 10

Chromosomes decondense, nuclear membrane reforms

Question 11

What is independent assortment?

Answer 11

When pairs of alleles separate independently from one another during gamete formation due to random orientation