Exam 2 Ch. 8

Question 1

How is asexual production involved in growth

Answer 1

Allows a cell to duplicate quickly and effectively. Cells duplicate themselves and split in half.

Question 2

How is asexual production involved in healing

Answer 2

If you cut yourself, new cells form by asexual cell division to heal the cut

Question 3

What is chromatin

Answer 3

DNA and associated histone proteins that have the appearance of thin threads.

DNA in its resting phase

Question 4

What are chromosomes

Answer 4

Tightly packaged chromatin

Question 5

When is the term sister chromatid used?

Answer 5

When duplicated chromosomes are attached by a centromere (sister chromatids have identical DNA)

Question 6

What is Interphase and why is it the longest cycle

Answer 6

A period in which the cell is not actively dividing and is carrying out its normal functions. A cell is in Interphase all the the time it is not dividing.

Question 7

What happens during G1

Answer 7

A cell doubles its organelles
Accumulates materials for DNA synthesis
Makes a decision whether to divide or not

Question 8

What happens during S phase?

Answer 8

DNA is replicated

Question 9

What happens in G2 Phase?

Answer 9

Growth phase
Protein synthesized as needed for cell division
Prepare to divide

Question 10

What does Mitosis mean

Answer 10

period of nuclear division

Question 11

Major events in Prophase

Answer 11

Chromosomes are condensing
Spindle begins to assemble
Nuclear envelope dissolves

Question 12

Major events in Metaphase

Answer 12

Chromosomes line up at the metaphase plate

Question 13

Major events in Anaphase

Answer 13

Sister chromatids separate as their pulled to opposite poles

Question 14

Major events in Telophase

Answer 14

Spindle disappears
New nuclear envelope forms
Daughter cells are identical to parent cells

Question 15

What does cytokinesis mean

Answer 15

Division of non-nuclear contents

Question 16

How is cytokinesis different from plant to animal cells

Answer 16

Animal cells furrow whereas plant cells wall prevents a cleavage furrow. A plant cell plate forms to separate cells

Question 17

What are the cell cycle checkpoints?

Answer 17

G1
G2
M

Question 18

What is checked at the G1 checkpoint

Answer 18

DNA integrity checked. If repair is not possible cell undergoes apoptosis

Question 19

What is checked at G2 checkpoint

Answer 19

Verifies DNA replicated

DNA damage repaired

Question 20

What is checked at the M checkpoint

Answer 20

All chromosomes must be attached to spindle to pass

Question 21

Example of a signal that would promote movement through the cell

Answer 21

Epidermal Growth Factor (EGF) stimulates skin near an injury to finish cell cycle and repair injury

Question 22

Example of a signal that would slow/stop cell cycle

Answer 22

Contact inhibition- cells stop dividing when they touch

Question 23

What is apoptosis

Answer 23

programmed cell death

unleashed by internal or external signals

Question 24

How is the cell cycle changed in cancer cells

Answer 24

Cellular reproduction occurs repeatedly without end
Cells dont respond to inhibitory signals
Cells dont undergo apoptosis

Question 25

What is an ongogene

Answer 25

Mutated proto-onco gene that has become cancer causing

Question 26

What is a proto-onco gene

Answer 26

Code for proteins that promote the cell cycle and inhibit apoptosis
(Accelerate cell cycle)

Question 27

What are tumor suppressor genes

Answer 27

codes for proteins that inhibit the cell cycle and promote apoptosis