1P: Meiosis

Question 1

Phases of meiosis I, prophase

Answer 1

Leptotene, zygotene, pachytene, diplotene, diakinesis

Question 2

Leptotene phase

Answer 2

Chromosome condensation (telomers bind to nuclear envelope)

Question 3

Zygotene phase

Answer 3

Synapsis of homologous chromosomes

Question 4

Are homologous chromosomes exact replicas?

Answer 4

No

Question 5

Are sister chromatids exact replicas?

Answer 5

Yes

Question 6

Pachytene phase

Answer 6

Crossing over = homologous recombination

Question 7

Diplotene phase

Answer 7

Chiasma (site of crossing over) becomes visible due to the separation of homologous chromosomes

Question 8

Diakinesis phase

Answer 8

Further chromosome condensation, nuclear envelope fragmenting

Question 9

Result of meiosis I

Answer 9

Two haploid, genetically different cells

Question 10

Result of meiosis II

Answer 10

Four haploid, genetically different cells

Question 11

Differences in meiosis prop. I -Spermatocyte and oocyte: Synapsis starts..

Answer 11

• Spermatocyte: At the end of the chromosomes

- Oocyte: Inside the chromosomes

Question 12

Differences in meiosis prop. I -Spermatocyte and oocyte: Synaptonemal complex

Answer 12

• Spermatocyte: Compact, shorter

- Oocyte: Less compact, longer

Question 13

Differences in meiosis prop. I -Spermatocyte and oocyte: Sites in chiasmata

Answer 13

• Spermatocyte: At the end of chromosomes

- Oocyte: Inside the chromosomes

Question 14

Differences in meiosis prop. I -Spermatocyte and oocyte: Number of chiasmata

Answer 14

• Spermatocyte: Less

- Oocyte: More