2.5 Cell Cycle

Question 1

What phases are included in interphase?

Answer 1

G1, S, and G2

Question 2

Describe the cell in G1.

Answer 2

Cell is smallest it will ever be at the beginning of this phase

Question 3

What happens during G1?

Answer 3

growth

Question 4

What happens during S Phase?

Answer 4

replication of DNA

Question 5

What is the S Phase referred to as?

Answer 5

synthetic phase

Question 6

What happens to cell in G2 phase?

Answer 6

cell grows and makes preparations for mitosis

Question 7

What happens to organelles in G2 phase?

Answer 7

organelles may increase in number

Question 8

What happens to DNA in G2 phase?

Answer 8

DNA begins to condense from chromatin to chromosomes

Question 9

What happens to microtubules in G2 phase?

Answer 9

microtubules begin to form

Question 10

What is step 1 of chromatin becoming chromosomes?

Answer 10

DNA wraps around histones to form nucleosomes

Question 11

What is step 2 of chromatin becoming chromosomes?

Answer 11

Nucleosomes wrap around further to form solenoids

Question 12

What is step 3 of chromatin becoming chromosomes?

Answer 12

Solenoids group together to form chromosomes

Question 13

What is step 1 of prophase?

Answer 13

Chromatin fibers tightly coiled to form chromosomes

Question 14

What is step 2 of prophase?

Answer 14

Nuclear envelope disintegrates

Question 15

What is step 3 of prophase?

Answer 15

Mitotic spindle begins to form, complete at end of prophase

Question 16

What is step 4 of prophase?

Answer 16

Centromere of each chromosome has region called “kinetochore” that attaches to spindle

Question 17

What is step 5 of prophase?

Answer 17

Centrosomes moves toward opposite poles of the cell due to lengthening microtubules

Question 18

What is step 1 of metaphase?

Answer 18

Chromosomes move to middle, or equator. This area is called the metaphase plate.

Question 19

What is step 2 of metaphase?

Answer 19

Chromosome’s centromere lies on the plate

Question 20

What is step 3 of metaphase?

Answer 20

Movement of chromosomes is due to action of the spindle which is made of microtubules.

Question 21

What is step 4 of metaphase?

Answer 21

Centrosomes now at opposite poles

Question 22

What is step 1 of anaphase?

Answer 22

Usually shortest phase, begins when two sister chromatids are split

Question 23

What is step 2 of anaphase?

Answer 23

Chromatids move to opposite poles of cell due to shortening of microtubules

Question 24

What is step 3 of anaphase?

Answer 24

Centromeres are attached to microtubules, so they are pulled first

Question 25

What is step 4 of anaphase?

Answer 25

At the end, each pole has identical set of chromosomes

Question 26

What is step 1 of telophase?

Answer 26

Chromosomes are at each pole

Question 27

What is step 2 of telophase?

Answer 27

Nuclear membrane begins to reform around each set of chromosomes

Question 28

What is step 3 of telophase?

Answer 28

Chromosomes start to elongate to form chromatin

Question 29

What is step 4 of telophase?

Answer 29

Nucleoli reappear

Question 30

What is step 5 of telophase?

Answer 30

Spindle apparatus disappears

Question 31

What is step 6 of telophase?

Answer 31

Cell is elongated and ready for cytokinesis (division)

Question 32

What is number 1?

Answer 32

centromere

Question 33

What is number 2?

Answer 33

chromatid

Question 34

What is number 3?

Answer 34

kinetochore

Question 35

What is number 4?

Answer 35

microtubules

Question 36

What phase is this?

Answer 36

prophase

Question 37

What phase is this?

Answer 37

metaphase

Question 38

What phase is this?

Answer 38

anaphase

Question 39

What phase is this and what is number 1?

Answer 39

telophase and cytokinesis, cleavage furrow