7 - Cell Cycle, mitosis and meiosis

Question 1

Telomeres

Answer 1

G rich ends of chromosomes

Question 2

Cohesins

Answer 2

proteins that join sister chromatids

Question 3

Kinetochores

Answer 3

Microtubule binding structure, one per chromatid, on either side of centromere. Microtubules attach to both kinetochores and pull sister chromatids apart

Question 4

What ware spindle microtubules composed of

Answer 4

Tubulin subunits

Question 5

Centrosome

Answer 5

Contains two centrioles at right angles. Where microtubules assemble

Question 6

Nondisjunction

Answer 6

Incorrect segregation of chromosomes

Question 7

homologous chromosomes

Answer 7

Two chromosomes in a pair

Question 8

chromatin

Answer 8

decondensed chromosome

Question 9

Phases of cell cycle

Answer 9

G1, S, G2, M

Question 10

Phases of M phase

Answer 10

Prophase, Prometaphase, Metaphase, Anaphase, Telophase

Question 11

Prometaphase

Answer 11

Nuclear membrane disintegrates. Spindle microtubules attach to kinetochores

Question 12

Prophase

Answer 12

Chromosomes condense. mitotic spindle forms

Question 13

Metaphase

Answer 13

Chromosomes line up on metaphase plate

Question 14

Anaphase

Answer 14

Sister chromatids seperate and move towards pols

Question 15

Results of mitosis

Answer 15

2 cells with same number of chromosomes as parent cells (both 2n)

Question 16

results of meiosis

Answer 16

4 cells with half the number of chromosomes as parent cells (each n)

Question 17

Crossing over

Answer 17

Unique to meiosis, exchange of genetic material between members of each homologous pair of chromosomes. Allows genetic variation

Question 18

Chiasma

Answer 18

Site of crossing over

Question 19

seperation of tetrads during anaphase 1

Answer 19

Cohesin along chromosome arms break down allowing homologs to seperate but cohesin at centromere is protected by shugoshin. Shugosin degraded allowing chromatids to seperate.

Question 20

Metaphase in mitosis

Answer 20

Individual chromosomes line up

Question 21

Metaphase in meiosis 1

Answer 21

Homologous pairs line up

Question 22

Metaphase in meiosis 2

Answer 22

Individual chromosomes line up

Question 23

When does crossing over occur

Answer 23

prophase 1

Question 24

Random & independent alignment of
chromosomes

Answer 24

Metaphase 1

Question 25

Random & independent distribution of chromosomes

Answer 25

Anaphase 1

Question 26

Anaphase in mitosis

Answer 26

Chromatids seperate

Question 27

Anaphase in meiosis 1

Answer 27

Homologous chromosomes seperate

Question 28

anaphase in meiosis 2

Answer 28

Chromatids seperate