Chapter 2 (Exam 2)

Question 1

Interphase

Answer 1

an extended period between cell divisions, DNA synthesis, and chromosome replication

Question 2

What phase does the cell grow in and produce the proteins necessary for cell division?

Answer 2

G1

Question 3

What phase does no cell division take place in?

Answer 3

G0

Question 4

What is one of the regulated decision point where the cell is committed to dividing?

Answer 4

G1/S phase

Question 5

What phase does the DNA duplicate in?

Answer 5

S phase

Question 6

What phase does the cell prepare to divide in?

Answer 6

G2

Question 7

What can only be passed if DNA is completely replicated and undamaged?

Answer 7

G2/M checkpoint

Question 8

What two processes occur in the M phase?

Answer 8

mitosis and cytokinesis

Question 9

Mitosis

Answer 9

seperation of sister chromatids

Question 10

Cytokinesis

Answer 10

separation of cytoplasm

Question 11

Prophase

Answer 11

-chromosomes condense
-each chromosome possesses two chromatids
-mitotic spindle forms

Question 12

Prometaphase

Answer 12

-nucelar membrane disintegrates
-spindle microtubules attach to chromatids

Question 13

Metaphase

Answer 13

chromosomes line up on the metaphase plate

Question 14

Anaphase

Answer 14

sister chromatids separate and move toward opposite poles

Question 15

Telophase

Answer 15

-chromosomes arrive at spindle poles
-nuclear membrane re-dorms and the chromosomes relax

Question 16

Meiosis

Answer 16

the production og haploid gametes

Question 17

What phase does DNA synthesis and chromosome replication occur?

Answer 17

Interphase

Question 18

When does seperation of homologous chromosome pairs, and reduction of the chromosome number by half (also called reduction division)

Answer 18

meiosis I

Question 19

What occurs in early prophase I?

Answer 19

chromosomes befin to condense and the spindle forms

Question 20

What occurs in late prophase I?

Answer 20

homologous chromosomes pair; crossing over takes place, and the nuclear membrane breaks down

Question 21

Synapsis

Answer 21

close pairing of homologous chromosomes in Prophase I

Question 22

Tetrad

Answer 22

closely associarted four sister chromatids of two homologous chromosomes in Prophase I

Question 23

Crossing Over

Answer 23

crossing over of chromosome segments from the sister chromatid of one chromosome to the sister chromatid of the other synapse chromosome-exchange of the genetic information; occurs in Prophase I

Question 24

What phase does random alignment of homologous pairs of chromosomes along the metaphase plate?

Answer 24

Metaphase I

Question 25

What phase do homologous chromosome pairs separate and randomly distribute chromsomes into the two newly divided cells?

Answer 25

Anaphase I

Question 26

What phase is the second mechanism of generating genetic variation in the newly formed gametes?

Answer 26

Anaphase I

Question 27

What phase do chromosomes arrive at the spindle poles and the cytoplasm divides?

Answer 27

Telophase I

Question 28

What is the final stage of Meiosis I and what occurs in it?

Answer 28

Interkinesis: period of rest that cells enter between meiosis I and II. No DNA replication occurs

Question 29

When do sister chromatids separate (also known as equatational division)?

Answer 29

Meiosis II

Question 30

What happens in Prophase II?

Answer 30

the chromosomes recondense

Question 31

What happens in Metaphase II?

Answer 31

individual chromosomes line up in the equatorial plate

Question 32

What happens in Anaphase II?

Answer 32

sister chromatids separate and move toward opposite poles

Question 33

What happens in Telophase II?

Answer 33

chromosomes arrive at the spindle poles and the cytoplasm divides

Question 34

Kinetochores

Answer 34

-formed on the centromere region of the chromosome -spindle microtubules attatch to the kinetochore

Question 35

What is the function of the shugosin protein?

Answer 35

prevents cohesin degradation during meiosis I; protects cohesin at the centromere; eventaully degraded and allows the centromere to break down and the chromatids to seperate

Question 36

Spermatogenesis

Answer 36

-male gamete production

Question 37

What is the order of spermatogenesis?

Answer 37

spermatogonium -->Primary Spermatocyte(2n)-->Secondary Spermatocytes (2n)-->Spermatids(1n) -->Sperm

Question 38

What is oogenesis?

Answer 38

female gamete production

Question 39

What is the order of oogenesis?

Answer 39

oogonium(2n)-->primary oocyte(2n)--> secondary oocyte (1n) and first polar body-->ovum(1n) and second polar body

Question 40

Sister Chromatids

Answer 40

held together by cohesin; when cohesin breaks down in mitosis it allows for separation of these

Question 41

What is the importance of cohesin in chromosomes?

Answer 41

it is key to the chromosomes behavior in mitosis