The Cell Cycle and Mitosis

Question 1

What phase is the cell in?

Answer 1

Anaphase

Fourth Part of the Cycle

Question 2

What phase is this cell in?

Answer 2

Cytokinesis

Question 3

What phase is this cell in?

Answer 3

Interphase

Question 4

What phase is this cell in?

Answer 4

Metaphase

Question 5

What phase is this cell in?

Answer 5

Prophase

Question 6

What phase is this cell in?

Answer 6

Telophase

Question 7

What is cell theory?

Answer 7

Cell Theory: All organisms consist of cells and arise from preexisting cells. This Requires that cells divide.

Question 8

Describe Mitosis

Answer 8

•Mitosis—new daughter cells are generated.

Produces identical cells

DNA is doubled during the process, and then divided to an identical amount in the two cells.

For growth and replacement

Question 9

Describe Meiosis

Answer 9

•Meiosis—gametes are generated for sexual reproduction.

Produces cells that are partially different genetically.

Net result is that the hereditary information reduced by one half.

For producing reproductive cells (gametes).

Question 10

What is prokaryotic cell cycle is called _______

Answer 10

Binary fission

Question 11

What is this a diagram of?

Answer 11

Prokaryotic (Bacterial) cell cycle

•single circular chromosome •replication of circular DNA •cell membrane and wall grow •cell wall and membrane fuse

Question 12

Express the purpose of mitosis in eukaryotes.

Answer 12

•To increase the number of cells and to distribute the parent cell’s genetic material to daughter cells during cell division –Prior to mitosis each chromosome is copied •Doubles the DNA content –During mitosis, one copy is distributed to each of the two daughter cells. •DNA content per cell returns to that identical to parent cell

Question 13

Replication is intiated at _____ along the length of eukaryotic chromosomes

DNA is copied in _____ direction(s) from ______ origin(s)

Answer 13

many points, both, multiple

Question 14

Define chromatin

Answer 14

•chromatin –DNA with packaging proteins

Question 15

Define histones

Answer 15

•histones –proteins that DNA wraps around for packaging

Question 16

Define chromatid

Answer 16

•chromatid –one double stranded DNA molecule, with packaging protein (before replication)

Question 17

Define sister chromatids

Answer 17

•sister chromatids –identical DNA double strands after replication

Question 18

Define centromere

Answer 18

•centromere –region of a duplicated chromosome that holds the two sister chromatids together

Question 19

Define
homologous chromosomes

Answer 19

•homologous chromosomes –Each individual has two copies of each type of chromosome (n types, 2n total chromosomes)

Question 20

How many chromosomes, DNA double helices, and chromatids are there in the unreplicated chromosome and replicated chromosome?

Answer 20

Unreplicated Chromosomes

Number of Chromosomes: 4

Number of DNA double helices: 4

Replicated Chromosomes

Number of Chromosomes: 4

Number of DNA double helices: 8

Each chromatid has 1 DNA double helix

Question 21

Explain the parts of the “cell cycle” and express the two key events that occur during the cycle.

Answer 21

•The orderly sequence of events that occurs: –from the formation of a eukaryotic cell, –through the duplication of its chromosomes, –to the time it undergoes division •During the cycle, two key events are: –Replication of the DNA in chromosomes –Partitioning the copied chromosomes to the two daughter cells

Question 22

Recognize and describe visual markers of cells in interphase, prophase, prometaphase, metaphase, anaphase, and telophase.

Answer 22

IPMAT

Question 23

Taxol is a drug that stabilizes spindle fibers and prevents them from shortening so that treated cells fail to complete mitosis. At which phase of mitosis are cells treated with taxol likely to stop?

a.interphase b. prophase c. metaphase d. anaphase e. telophase

Answer 23

C. Metaphase

Question 24

Explain why taxol is an “anticancer” drug and the effects of cancer chemotherapy

Answer 24

•Because it stops cell division •It is a cell cycle specific drug •Cancer cells are relatively rapidly dividing

Question 25

Which phase of the cell cycle is represented?

Answer 25

Metaphase