Ch:8 Mitosis and the Cell Cycle

Question 1

Mitosis is only a small part of the cell cycle. 90% of the cell cycle is _______. During this phase we see ______ and ______________ in order to prepare for cell division

Answer 1

Interphase = 90% of the cell cycle

Growth and chromosomes are copied

Question 2

During which phase of the cell cycle is growth and making of organelles and proteins seen?

Answer 2

Interphase

Question 3

Explain what occurs in each of the following phases of the cell cycle:

1. G1
2. S-phase
3. G2

Answer 3

G1: cell begins to grow

S-Phase: duplication of chromosomes

G2: Cell prepares to divide

Question 4

During mitosis, chromosomes are moved by a

_______(2 words)________ composed of _______.

Answer 4

Spindle apparatus composed of microtubules

Question 5

The assembly of the spindle apparatus begin at a structure called the _________.

Answer 5

Centrosome

Question 6

What is a centrosome composed of?

Answer 6

2 centrioles perpendicular to each other

Question 7

Do plants have centrioles or a mitotic spindle?

Answer 7

Plants don’t have centrioles but do have a mitotic spindle

Question 8

What technique allows you to view chromosomes?

Answer 8

Karyotyping

Question 9

What 4 things occur during Prophase of the cell cycle?

Answer 9

1. Nucleoli disappear
2. Chromosomes condense
3. Centrioles move to opposite poles
4. Mitotic spindle begins forming
5. chromosomes become tightly coiled and are now viewable under a light microscope

Question 10

What type of microscope can you use to view chromatin?

Answer 10

Light microscope

Question 11

What occurs during pro metaphase of the cell cycle?

Answer 11

1. Nuclear envelope surrounds the nucleus

2. Some of the microtubules attach to the kinetochore.

Question 12

What is the kinetochore?

Answer 12

A kinetochore is a protein structure attached to the centromere that links the sister chromatids to the mitotic spindle.

“IT IS VITAL YOU UNDERSTAND THIS”

Question 13

What occurs during metaphase of the cell cycle?

Answer 13

1. Centrosomes are officially at opposite ends
2. Sister chromatids of each chromosome are attached to the spindle
3. Chromosomes line up at the spindle equator

Question 14

Which phase in mitosis of the cell cycle is the shortest phase?

Answer 14

Anaphase

Question 15

What occurs during anaphase of the cell cycle? (2 things happen)

Answer 15

1. Sister chromatids separate and move to opposite poles

2. Cytokinesis begins at the end of anaphase***

Question 16

What occurs during Telophase of the cell cycle?

Answer 16

1. two daughter nuclei form, each with diploid 2N number
2. Cytokinesis occurs, but often begins a bit earlier
3. Chromosomes decondense
4. New nuclear membranes form

Question 17

In animal cells, cytokinesis involves the formation of a _____(2 words)_____.

Answer 17

Cleavage furrow

Question 18

Plants don’t have a cleavage furrow, instead they have a ___(2 words)___.

Answer 18

Plants = cell plate

Animals = cleavage furrow

Question 19

_______ is a mitotic poison that destroys microtubules.

Answer 19

Colchicine

“FAVORITE DAT-TYPE QUESTION”

Question 20

Define each of the following:

• Somatic cells
• Gametes
• Genome

Answer 20

Somatic cells: all cells except reproductive cells

Gametes: eggs or sperm cells

Genome: the genetic info in a cell

Question 21

Define each of the following:

• Aster
• Spindle
• Zygote

Answer 21

Aster: an array of microtubules that extends from each centrosome

Spindle: structure made up of proteins and microtubules. The spindle includes centrosomes, asters and microtubules.

Zygote: fertilized egg (2N)

Question 22

Define each of the following:

• Apoptosis
• Tumor
• Neoplasm

Answer 22

Apoptosis: programmed cell death

Tumor: Clump of overlapping cells (can be malignant or benign)

Neoplasm: a new and abnormal growth

Question 23

What 2 factors limit cell size?

Answer 23

1. Nucleus capacity: must have enough DNA

2. Surface area to volume ratio (volume increases at a faster rate then surface area)