Chapter 12

Question 1

Do cells spontaneously appear, or do they arise through preexisting cells?

Answer 1

Preexisting cells

Question 2

What is cell division that results in asexual reproduction in bacteria called?

Answer 2

binary fission

Question 3

What is the circular DNA in prokaryotes called specifically?

Answer 3

Nucleoid

Question 4

What are the two types of cell division found in eukaryotes? Explain both.

Answer 4

1) Meiosis- produces genetically different gametes (eggs and sperm) that are haploids
2) Mitosis- produces all other cell types referred to as somatic cells

Question 5

What is mitosis (and cytokinesis) significant for? (Hint: There are 3 major functions.)

Answer 5

Growth, Replace damaged cells, Asexual reproduction.

Question 6

How is DNA packaged in chromosomes?

Answer 6

DNA wraps around his tone proteins and packaged as chromosomes.

Question 7

Define chromatid.

Answer 7

Each of the DNA copies in a replicated chromosome

Question 8

Define sister chromatids.

Answer 8

Chromatids from the same chromosome

Question 9

What is the structure where sister chromatids join together called?

Answer 9

Centromere

Question 10

How many chromosomes are there when there are 2 sister chromatids? (Hint: Chromosome looks like an X in shape.)

Answer 10

1 chromosome 46

Question 11

Define chromatin.

Answer 11

The material that makes up eukaryotic chromosomes, consists of a DNA molecule complexed with his tone proteins

Question 12

Define kinetochore.

Answer 12

The structures on sister chromatids where microtubules attach

Question 13

What is the microtubule-organizing center called?

Answer 13

Centrosome

Question 14

What are the cylindrical structures that make microtubules called?

Answer 14

Centioles

Question 15

What are the two phases of the cell cycle? Explain both.

Question 16

Explain what occurs during the G1 phase.

Question 17

Explain what occurs during the S phase.

Question 18

Explain what occurs during the G2 phase.

Question 19

Name the phase that nondividing cells stay in. Give an example of a cell type that is in this stage.

Question 20

What criteria must the cell meet to pass the G1 checkpoint?

Question 21

What criteria must the cell meet to pass the G2 checkpoint?

Question 22

What criteria must the cell meet to pass the M-phase checkpoints?

Question 23

What induces mitosis in all eukaryotes? (Hint: It is found in the cytoplasm of eukaryotic cells.)

Question 24

What are the two subunits that comprise MPF? Explain both.

Question 25

Does Cdk’s concentration change? Does cyclin’s concentration change?

Question 26

When is Cdk considered active?

Question 27

If Cdk has ONE phosphate attached it is: active/inactive? If Cdk has TWO phosphates attached it is :active/inactive?

Question 28

Once MPF is activated, mitosis is triggered by? (Hint: There are 2 points to the answer.)

Question 29

List the five sub phases in mitosis, in order.

Question 30

Summarize what occurs in prophase.

Question 31

What are microtubules composed of?

Question 32

What is the function of microtubules?

Question 33

What happens to the nuclear envelope during prometaphase?

Question 34

What do the microtubules do during prometaphase? Where do they attach specifically?

Question 35

Summarize what occurs in metaphase.

Question 36

The imaginary plane formed by metaphase is called the _________ ?

Question 37

How is it that the sister chromatids separate in anaphase?

Question 38

Where does depolymerization occur? The + or - end of the kinetochore microtubule?

Question 39

Summarize the events of telophase.

Question 40

Define cytokinesis.

Question 41

What creates the cell plate found in plants?

Question 42

What are the filaments called that cause a pinch in the cell membrane? What is this pinch called? (Hint: This “pinch” occurs in animals.)

Question 43

What is the tumor suppressor protein? And what does it do?

Question 44

Uncontrollable division of one or more cells in a multicellular organism leads to ______?

Question 45

What are the two types of defects that cancerous cells can have?

Question 46

Compare the difference between benign tumors and malignant tumors.

Question 47

What occurs during metastasis?