Chapter I: Nucleic Acid Structure and Organization

Question 1

Transcription.

Answer 1

process of DNA going to RNA

Question 2

Translation

Answer 2

process of RNA being made into protein

Question 3

Transcription occurs in what phase of the cell cycle?

Answer 3

throughout interphase

Question 4

What part of the cell does transcription take place?

Answer 4

nucleus

Question 5

What phase of the cell cycle does DNA replication occur?

Answer 5

During S phase

Question 6

Where does translation of RNA occur? What phase?

Answer 6

in the cytoplasm; throughout the cell cycle

Question 7

Describe M phase of the cell cycle.

Answer 7

mitosis the time in which the cell divides to form 2 daughter cells

Question 8

Interphase?

Answer 8

the time between 2 cell divisions or mitosis

Question 9

What is interphase divided into?

Answer 9

G1, S, G2 phase

Question 10

G1 phase? (another name for it)

Answer 10

(gap 1)

period of cellular growth preceding DNA synthesis

Question 11

G0 phase? Examples?

Answer 11

cells that have stopped cycling, such as muscle and nerve cells are said to be in a special state called G0

Question 12

S phase

Answer 12

DNA synthesis; when DNA replication occurs

Question 13

G2 phase? Another name for it?

Answer 13

gap 2

period of cellular growth after DNA synthesis but preceding mitosis; replicated DNA is checked for any errors before cell division

Question 14

Reverse transcription?

Answer 14

produces DNA copies of RNA and more commonly associated with life cycles of retroviruses, which replicate and express their genome through a DNA intermediate (an integrated provirus)

Question 15

What are the 2 types of nucleic acids?

Answer 15

DNA and RNA

Question 16

What are DNA and RNA assembled from?

What are the 3 components?

Answer 16

nucleotides, which consist of 3 components:
a nitrogenous base, a 5-carbon sugar (pentose), and phosphate

Question 17

Difference beween nucleic acids and nucleotides?

Answer 17

nucleic acids are polymers of nucleotides

Question 18

What are some purines?

Answer 18

Pure As Gold

adenine
guanine

Some other purine metabolites not usually found in nucleic acids:
xanthine, hypoxanthine, and uric acid

Question 19

Pyramidines names?

Answer 19

cytosine, uracil, thymine

Question 20

Difference between adenine and guanine structure?

Answer 20

adenine has amino group at the top

Question 21

Difference between cytosine uracil and thymine structure?

Answer 21

cytosine has amino group at the top

uracil and thymine have the same structure but thymine has a methyl group on the side

Question 22

How do you tell the difference between naming a structure with the prefix deoxy?

Answer 22

on the pentose sugar if there is no OH on the right side (2’) position

Question 23

Suffix for naming most nucleosides?

Answer 23

“sine” (for purines) or “dine” (for pyrimidines)

adenosine
guanosine
cytidine
uridine
thymidine

Question 24

Is the DNA double helix usually right or left handed? Also what is another name for the most commonly found type of DNA?

Answer 24

right handed (B- DNA)

Question 25

How does Daunorubicin and doxorubicin exert their effects? What is daunorubicin and doxorubicin often used for?

Answer 25

anti-tumor drugs that are used in treatment of leukemias

exert their effects by intercalating between the bases of DNA, thereby interfering with the activity of topoisomerase II and preventing proper replication of DNA

Question 26

Hybridization?

Answer 26

when probe DNA binds to target DNA sequences of sufficient complementarity

Question 27

Negatively supercoiled DNA?

Answer 27

formed if DNA is wound more loosley than in Watson-crick DNA. (required for most biologic reactions)

Question 28

Positively supercoiled DNA?

Answer 28

formed in DNA is wound more tightly than in Watson Crick DNA

Question 29

Topoisomerases

Answer 29

enzyme that can change the amount of supercoiling in DNA molecules.

They make transient breaks in DNA strands by alternately breaking and resealing sugar-phosphate backbone

Question 30

Histones are rich in what amino acids?

Answer 30

arginine and lysine

Question 31

Lysine and arginine are both (positively or negatively charged) amino acids?

Answer 31

positively charged

Question 32

What comprises the histone octomer?

Answer 32

2 copies of each histones:

H2A
H2B
H3,
H4

Question 33

10 nm chromatin

Answer 33

Whe DNA is wound around outside of the histone octamer to form a nucleosome (a series of nucleosomes called “beads on a string”

Question 34

30 nm fiber?

Answer 34

When histone H1 is associated with the linker DNA found between nucleosomes to help package them a solenoid-like structure is formed which is referred to as 30 nm DNA

Question 35

Euchromatin

Answer 35

chromatin that is more open and available for gene expression

Question 36

Heterochromatin

Answer 36

chromatin more highly condensed and associated with areas of chromosomes that are not expressed

Question 37

Does heterochromatin typically correspond to (10 nm or 30 nm fibers)?

Answer 37

30 nm fibers