Chapter 4.3: Mitosis: Cell Division that Reserves Chromosome Number

Question 1

In what phase of mitosis does  The now separated sister chromatids move to opposite poles?

Answer 1

anaphase

Question 2

In what phase of mitosis does  Chromosomes align on the metaphase plate with sister chromatids facing opposite poles?

Answer 2

metaphase

Question 3

What are kinetochore microtubules, or centrometric fibers?

Answer 3

• Microtubules that extend between a chromosome and the kinetochore of a chromatid

Question 4

What is a structure in the centromere region of each chromatid that is specialized for conveyance?

Answer 4

kinetochore

Question 5

In what phase of mitosis does  Chromosomes condense and become visible?

Answer 5

prophase

Question 6

Describe Gap 1 phase

Answer 6

o Gap 1 (G1) is cell growth

 Lasts from the birth of a new cell to the onset of chromosome replication

Question 7

Describe cytokinesis in plants

Answer 7

• in plants, a membrane enclosed disk, known as the cell plate, forms inside the cell near the equator and then grows rapidly outward, thereby dividing the cell in two

Question 8

In what phase of mitosis does  Nuclear membranes and nucleoli re-form?

Answer 8

telophase

Question 9

Describe chromatin

Answer 9

 Each convoluted thread of chromatin is composed mainly of DNA (which carries the genetic information) and protein (which serves as a scaffold for packaging and managing the information)

Question 10

In what phase of mitosis does  Nuclear envelope breaks down?

Answer 10

prometaphase

Question 11

Descibe cytokinesis of mitosis (1)

Answer 11

 The cytoplasm divides, splitting the elongated parent cell into two daughter cells with identical nuclei

Question 12

In what phase of mitosis does  Spindle fibers disappear?

Answer 12

telophase

Question 13

What is the nuclear division that apportions chromosomes in equal fashion to two daughter cells, is the cellular mechanism that preserves genetic information through all these generations of cells?

Answer 13

mitosis

Question 14

In what phase of mitosis does  Microtubules from the centromeres invade the nucleus?

Answer 14

prometaphase

Question 15

What is the kinetochore?

Answer 15

a structure in the centromere region of each chromatid that is specialized for conveyance

Question 16

What are • Microtubules from each chromosome that are directed toward the middle of the cell?

Answer 16

polar microtubules

Question 17

Where do microtubules come from?

Answer 17

 Microtubules radiate out into the cytoplasm from a single organizing center known as the centrosome, usually located near the nuclear envelope

Question 18

Describe Synthesis (S) phase of mitosis

Answer 18

o Synthesis (S) is the time when the cell duplicates its genetic material by synthesizing DNA

Question 19

What is a coenocyte?

Answer 19

 a multinucleate plant tissue

Question 20

What forms the mitotic spindle?

Answer 20

kinetochore microtubules, polar microtubules, and astral microtubules

Question 21

In what phase of mitosis does  Nucleoli begin to disappear?

Answer 21

prophase

Question 22

What is o The repeating pattern of cell growth (an increase in size) followed by division?

Answer 22

cell cycle

Question 23

What is  an animal cell with 2 or more nuclei?

Answer 23

synctium

Question 24

What phase of mitosis is cell growth?

Answer 24

Gap 1

Question 25

Describe telophase of mitosis (3)

Answer 25

 Nuclear membranes and nucleoli re-form
 Spindle fibers disappear
 Chromosomes uncoil and become a tangle of chromatin

Question 26

When are the regulatory checkpoints during mitosis?

Answer 26

o After S phase
o After G2 phase
o After metaphase

Question 27

Describe metaphase of mitosis (1)

Answer 27

 Chromosomes align on the metaphase plate with sister chromatids facing opposite poles

Question 28

What are astral microtubules?

Answer 28

• Short astral microtubules extend out from the centrosome toward the cell’s periphery

Question 29

Describe cytokinesis in animals

Answer 29

• In animals, cytoplasmic division depends on a contractile ring that pinches the cell into two halves

Question 30

Where do the sister chromatids attach to microtubules at?

Answer 30

kinetochore

Question 31

In what phase of mitosis does  Centrosomes move apart toward opposite poles and generate new microtubules?

Answer 31

prophase

Question 32

What is  a multinucleate plant tissue?

Answer 32

coenocyte

Question 33

What is mitosis?

Answer 33

the nuclear division that apportions chromosomes in equal fashion to two daughter cells, is the cellular mechanism that preserves genetic information through all these generations of cells

Question 34

What are centrioles?

Answer 34

 In animal cells, the discernable core of each centrosome is a pair of small, darkly staining bodies called centrioles

Question 35

What is a synctium?

Answer 35

 an animal cell with 2 or more nuclei

Question 36

Describe Gap 2 phase of mitosis

Answer 36

o Gap 2 (G2) is the interval between chromosome duplication and the beginning of mitosis
 Cell may grow; also synthesizes proteins for mitosis

Question 37

In what phase of mitosis does  Centromeres divide?

Answer 37

anaphase

Question 38

In what phase of mitosis does  Sister chromatids attach to microtubules from opposite centromeres?

Answer 38

prometaphase

Question 39

In what phase of mitosis does  The cytoplasm divides, splitting the elongated parent cell into two daughter cells with identical nuclei?

Answer 39

cytokinesis

Question 40

What are polar microtubules?

Answer 40

• Microtubules from each chromosome that are directed toward the middle of the cell

Question 41

Describe prophase of mitosis (3)

Answer 41

 Chromosomes condense and become visible
 Centrosomes move apart toward opposite poles and generate new microtubules
 Nucleoli begin to disappear

Question 42

Describe prometaphase of mitosis (3)

Answer 42

 Nuclear envelope breaks down
 Microtubules from the centromeres invade the nucleus
 Sister chromatids attach to microtubules from opposite centromeres

Question 43

What type of microtubules extend out from the centrosome toward the cell’s periphery?

Answer 43

astral microtubules

Question 44

Describe chromosomes

Answer 44

o Chromosomes resemble a mass of extremely fine tangled string—called chromatin—surrounded by the nuclear envelope

Question 45

What is the purpose of the nucleolus?

Answer 45

 Nucleolus (dark area of chromatin) plays a key role in the manufacture of ribosomes, organelles that function in protein synthesis

Question 46

In what phase of mitosis does  Chromosomes uncoil and become a tangle of chromatin?

Answer 46

telophase

Question 47

What are • Microtubules that extend between a chromosome and the kinetochore of a chromatid?

Answer 47

kinetochore microtubules

Question 48

Define cell cycle

Answer 48

o The repeating pattern of cell growth (an increase in size) followed by division

Question 49

Describe anaphase of mitosis (2)

Answer 49

 Centromeres divide

 The now separated sister chromatids move to opposite poles