D2.1 Cell and Nuclear Division

Question 1

(1) Interphase - G1 phase

Answer 1

• Occurs in cytoplasm
• Cell doubles in size

Question 2

(2) Interphase - S phase

Answer 2

• DNA replication occurs
• Amount of DNA doubles

Question 3

(3) Interphase - G2 phase

Answer 3

• Grows in size
• Develops microtubules

Question 4

Cell proliferation

Answer 4

Process of cellular division + replication

Question 5

Cyclins

Answer 5

Proteins regulating cell cycle

Question 6

(1) Prophase

Answer 6

• nuclear membrane disintegrates
• microtubules migrate to poles
• (in meiosis) crossing over occurs

Question 7

Crossing over

Answer 7

Process in which homologous chromosomes exchange genetic material. Only occurs in Meiosis 1

Question 8

Homologous chromosomes

Answer 8

)( -> pairs of sister chromatids that have the same structure and size, and contain genes for the same traits at the same locations

Question 9

Bivalent )()(

Answer 9

)()( -> Structure formed when two homologous chromosomes (each consisting of two sister chromatids) pair up during Prophase I of meiosis.

Question 10

(2) Metaphase

Answer 10

• spindle fibers attach to centromeres of chromosomes and pull bivalents to the center
• (in meiosis) random orientation occurs

Question 11

(3) Anaphase

Answer 11

• Spindle fibers shorten, pulling chromatids apart to poles

Question 12

(4) Telophase

Answer 12

• nuclear membrane reforms
• chromosomes decondense
• spindle fibers break down

Question 13

Chiasma

Answer 13

Point at which crossing over occurs

Question 14

Recombinant

Answer 14

bivalent after it has undergone crossing over

Question 15

Mitotic index

Answer 15

Number of actively dividing cells/ Total number of cells

Question 16

Mitosis

Answer 16

Produces two identical diploid daughter cells

Question 17

Meiosis

Answer 17

Produces four haploid unique daughter cells