Cell Cycle Test

Question 1

What are the two main stages in the cell cycle?

Answer 1

Interphase and mitosis

Question 2

What are the phases in interphase?

Answer 2

Gp 1, Synthesis, Gap 2

Question 3

What happens in Gap 1

Answer 3

cell grows in size
duplicates organelles
cell’s “birthday”

Question 4

What happens at the Gap 1 checkpoint?

Answer 4

checks if enough nutrients are present
checks for damaged DNA

Question 5

What happens in the S phase?

Answer 5

centrosomes duplicate
DNA duplicate

Question 6

What happens in the Gap 2 phase?

Answer 6

cell grows in size
cell prepares to divide

Question 7

What happens at the G0 checkpoint?

Answer 7

cell is not duplicating its DNA
cell is not dividing

Question 8

What are the stages of mitosis?

Answer 8

Prophase, Metaphase, Anaphase, Telophase

Question 9

What happens in prophase?

Answer 9

mitotic spindle forms
nuclear envelope breaks down
chromosomes start to form

Question 10

What happens in prometaphase (late prophase)?

Answer 10

growing spindle
centrosomes at poles
nuclear envelope broken down

Question 11

What happens in metaphase?

Answer 11

centrioles at poles
sister chromatids at the metaphase plate

Question 12

What happens in anaphase?

Answer 12

chromosomes pulled to poles
microtubules (spindle fibers) push apart
chromatids pulled apart

Question 13

What happens in telophase?

Answer 13

spindle breaks down
nuclear envelope reforms
chromosomes decondense (into chromatin)

Question 14

What is a nucleotide made of

Answer 14

phosphate group, 5-carbon sugar, nitrogen base

Question 15

What is the difference between purines and pyrimidines?

Answer 15

Purines: 2 rings
Pyrimidines: 1 ring

Question 16

What nitrogenous bases are purines?

Answer 16

Adenine and Guanine

Question 17

What nitrogenous bases are pyrimidines?

Answer 17

Thymine and Cytosine

Question 18

What are the four nitrogenous bases?

Answer 18

Adenine, Thymine, Guanine, Cytosine

Question 19

What bonds hold the 2 DNA strands together?

Answer 19

hydrogen bonds

Question 20

What are the backbones of the strands made of?

Answer 20

phosphate-sugar backbones

Question 21

DNA runs -

Answer 21

5’ - 3’ (5 prime to 3 prime)
*the 5 prime is the nitrogenous base with the phosphate group on top (see images in Notes+)

Question 22

DNA is ___

Answer 22

Antiparallel
(One strand runs 5’ to 3’, while the other runs 3’ to 5’. This means that one is upside down…basically)

Question 23

DNA Replication begins at the ____

Answer 23

Origin of replication

Question 24

Which cells have multiple origins of replication?

Answer 24

Eukaryotic cells

Question 25

What is the benefit of having multiple origins of replication?

Answer 25

It makes DNA duplication faster

Question 26

What occurs at the replication fork?

Answer 26

DNA replication

Question 27

DNA replication takes place in ___ directions

Answer 27

Both

Question 28

DNA replication take place moving ____

Answer 28

Away from the origin of replication

Question 29

Replication forks are created at

Answer 29

the origin of replication

Question 30

How do replication bubbles form

Answer 30

When the replication forks move apart

Question 31

What happens when the replication bubbles connect with other bubbles that have formed around other origins of replications

Answer 31

they collide and 2 new strands of DNA are made

Question 32

Topoisomerase role

Answer 32

unwinds DNA

Question 33

Helicase role

Answer 33

Breaks the hydrogen bonds (which separates the nitrogenous bases)

Question 34

SSB role

Answer 34

keep the 2 strands separated

Question 35

DNA polymerase role

Answer 35

Adds new nucleotides to DNA strand being created

Question 36

How does DNA polymerase know what nucleotide to add next?

Answer 36

It reads the bases on the original and adds the complementary bases

Question 37

DNA polymerase can only add new bases ____ to a strand of DNA. What does this result in?

Answer 37

5’ to 3’; this results in one being made continuously and another made in fragments

Question 38

continuously-made strand called

Answer 38

Leading strand

Question 39

Strand made in small segments called

Answer 39

Lagging strand

Question 40

Lagging strand segments called

Answer 40

Okazaki fragments

Question 41

Okazaki Fragments are joined together by

Answer 41

DNA ligase

Question 42

What does DNA ligase do to glue the fragments together?

Answer 42

it forms a covalent bond between deoxyribose sugar and a phosphate group of another

Question 43

DNA primase role

Answer 43

adds an RNA primer that lets DNA polymerase know where to add new nucleotides