Topic 2 (Cell division and genetics)

Question 1

The three main stages of cell cycle (3)

Answer 1

1)Interphase
2)Mitosis
3)Cytokynesis

Question 2

The three stages of interphase (3)

Answer 2

1)G1
2)S
3)G2

Question 3

What happens in G1 phase

Answer 3

Replication of organelles

Question 4

What happens in S phase

Answer 4

Replication of DNA

Question 5

What happens in G2 phase

Answer 5

Mitochondria and Chloroplast replication

Question 6

The four stages of mitosis (4)

Answer 6

1)Prophase
2)Metaphase
3)Anaphase
4)Telophase

Question 7

What happens in prophase (5)

Answer 7

1)Chromatin condense into visible chromatids
2)Sisiter chromatids join at centromere
3)Centrioles position at opposite poles of the cell
4)Spindle fibres form
5)Nucleolus disappear

Question 8

What happens in metaphase (3)

Answer 8

1)Nuclear envelope break down
2)Chromosome line up along the equator
3)Become attached to spindle fibre

Question 9

What happens in anaphase (2)

Answer 9

1)Spindle fibre pull the sister chromatids to opposite poles of the cell (separation of sister chromatids)
2)Spindle fibres break down

Question 10

What happens in telophase (2)

Answer 10

1)Chromatids decondense into Chromatin
2)nuclear envelope reform

Question 11

What is the purpose of mitosis (3)

Answer 11

produce cells for
1)Growth
2)Repair damaged tissue cells
3)Asexual reproduction

Question 12

The products of mitosis (2)

Answer 12

1)Two genetically identical daughter cells
2)Both diploid

Question 13

The key stages of meiosis (2)

Answer 13

1)Meiosis I
2)Meiosis 2

Question 14

What happens in prophase during meiosis I (7)

Answer 14

1)Homologous chromosome pair up side by side (bivalent)
2)Crossing over via chiasmata formation resulting in recombinant of alleles

Question 15

What happens in metaphase during meiosis I (5)

Answer 15

Independent assortment of homologous chromosome

Question 16

What happens in telophase during meiosis

Answer 16

formation of two genetically different cells

Question 17

What are the products of meiosis (2)

Answer 17

1)Four non-gentically identical daughter cells
2)Haploid

Question 18

What are the products of meiosis (2)

Answer 18

1)Four non-gentically identical daughter cells
2)Haploid

Question 19

How does separation failure leads to chromosomal mutation during anaphase (2)

Answer 19

1)polyspermy leads to Down’s syndrome
2)Monosomy leads to Turner’s syndrome