Cell Cycle

Question 1

What are the four stages of the cell cycle?

Answer 1

Gap 1, synthesis, Gap 2, Mitosis

Question 2

Gap 1

Answer 2

Cell growth and checkpoint for DNA synthesis

Question 3

DNA synthesis

Answer 3

Copies DNA

Question 4

Gap 2

Answer 4

Additional growth and checkpoint for cell size/ DNA damage

Question 5

What are the disadvantages of cells being too small/big?

Answer 5

if it’s too small they won’t contain the necessary organelles and if it is too big there can be an inadequate exchange of materials.

Question 6

Cytokinesis

Answer 6

Division of cytoplasm and is the final step in the cell cycle

Question 7

Chromosome

Answer 7

DNA double helix-> DNA & histones-> Chromatin-> Supercoiled DNA

Question 8

Chromosome anatomy

Answer 8

the ends are called telomeres that protect the DNA, one half is called chromatid, the middle is the centromere.

Question 9

Interphase

Answer 9

DNA is duplicated

Question 10

Prophase

Answer 10

Chromosomes condense and spindle fibers form with the help of centrioles. Nuclear membrane disappears

Question 11

Metaphase

Answer 11

Chromosomes line in the middle of the cell

Question 12

Anaphase

Answer 12

Sister chromatids separate to opposite sides of the cell

Question 13

Telophase

Answer 13

Chromosomes begin to uncoil

Question 14

Cytokinesis in plant/ animal

Answer 14

animal- membrane pinches closed plant- cell plate forms

Question 15

Why do cells divide?

Answer 15

for reproduction, growth, and repair/renewal

Question 16

What cells grow/mature and never divide again?

Answer 16

Brain/nerve cells

Question 17

Prometaphase

Answer 17

spindle fibers attach to centromeres creating kinetochores.

Question 18

How did mitosis evolve

Answer 18

from binary fission in bacteria

Question 19

Cell regulation

Answer 19

the coordination of cell division

Question 20

What are two irreversible points in the cell cycle?

Answer 20

replication of genetic material and separation of sister chromatids

Question 21

Where are the checkpoints for the cell cycle?

Answer 21

Between G1 and S, Between G2 and Mitosis, after metaphase

Question 22

The G1/S checkpoint

Answer 22

if the cell receives the “go” signal the cell divides. Internal signals are growth & nutrition and external are growth factors

Question 23

CDK

Answer 23

Cyclin-dependent kinase; activates or inhibits proteins

Question 24

Cyclin

Answer 24

regulatory proteins; levels the cell cycle

Question 25

G-zero phase

Answer 25

non-dividing stage; most human cells are in here

Question 26

How do cells know when to divide?

Answer 26

There are chemical signals; the signals=proteins

Question 27

G2/Mitosis checkpoint

Answer 27

make sure replication is completed

Question 28

Metaphase checkpoint

Answer 28

The chromosome is attached to the metaphase plate

Question 29

2 types of growth factors

Answer 29

density-dependent inhibition- crowded cells don’t divide. anchorage-dependent- cells need to be attached to a substrate to divide.

Question 30

What can cause cancer?

Answer 30

growth factors like proto-oncogenes or tumor suppressor genes.

Question 31

What control is lost when cancer erupts?

Answer 31

checkpoints stop, gene p53 stops cell replication if there is DNA damage`

Question 32

What mutations do cells go through?

Answer 32

unlimited growth, missing checkpoints, escaping apoptosis, unlimited divisions, promotes blood vessel growth, overcome density dependence, and anchor.

Question 33

Benign tumor

Answer 33

does not spread and stays in the original site

Question 34

Malignant tumor

Answer 34

spread throughout the body and can start new tumors ( metastasis)

Question 35

What does chemotherapy do?

Answer 35

stops DNA replication stops mitosis/cytokinesis and stops blood vessel growth