Molecular genetics

Question 1

At which carbon of ribose is the base attached in RNA/DNA?

Answer 1

C1

Question 2

What makes up a nucleosome?

Answer 2

eight histones + DNA

Question 3

Name the purines. Name the pyrimidines.

Answer 3

purines: adenine, guanine
pyrimidines: thymine, cytosine, uracil

Question 4

Where are purines and pyrimidines synthesized?

Answer 4

liver, brain

Question 5

In what part of the cell cycle does DNA replicate?

Answer 5

S phase

Question 6

What is a nucleoside? What is a nucleotide?

Answer 6

nucleoside = purine/pyrimidine base + sugar

nucleotide = nucleoside + phosphate

Question 7

During which phase of the cell cycle does the cell rest between divisions?

Answer 7

interphase

Question 8

Name the 3 subdivisions of interphase.

Answer 8

G1, S, G2

Question 9

Name the phase of the cell cycle that certain cells (e.g. muscle and nerves) can rest indefinitely in.

Answer 9

G0

Question 10

A sample of double-stranded DNA has 10% G. What is the percentage of T?

Answer 10

40%

Question 11

During which phase of the cell cycle do daughter cells form?

Answer 11

M phase

Question 12

Are histones positively or negatively charged?

Answer 12

positively charged

Question 13

Name the phase of the cell cycle in which newly synthesized DNA is checked for errors.

Answer 13

G2

Question 14

Name the bonds that hold strands of DNA together.

Answer 14

Hydrogen bonds: adenine to thymine (2 bonds) and guanine to cytosine (3 bonds)

Question 15

Which has two rings: the pyrimidines or the purines?

Answer 15

purines have two rings

pyrimidines have only one ring

Question 16

Where in the cell does DNA replication occur?

Answer 16

nucleus

Question 17

In what part of the cell does transcription occur?

Answer 17

nucleus

Question 18

Name the phase of the cell cycle that immediately precedes DNA synthesis.

Answer 18

G1

Question 19

Name the phase of the cell cycle in which DNA replication occurs.

Answer 19

S

Question 20

How many carbons are in ribose?

Answer 20

5

Question 21

At which carbons of ribose is the phosphodiester bond formed?

Answer 21

C3 and C5

Question 22

At which end of a DNA sequence is the hydroxy group? At which end is the free phosphate group?

Answer 22

3’

5’

Question 23

What is the functional difference between euchromatin and heterochromatin?

Answer 23

euchromatin is loosely packaged and readily transcribed

heterochromatin is tightly wound and cannot be transcribed

Question 24

At physiological pH, is DNA/RNA positively or negatively charged?

Answer 24

negative

Question 25

Which carbon of ribose is lacking a hydroxy group in DNA?

Answer 25

C2

Question 26

Which has a higher melting point: DNA with a lot of A=T or DNA with a lot of G=C?

Answer 26

High G=C content

Question 27

Name the only part of the cell cycle that is not part of interphase.

Answer 27

M phase

Question 28

In what part of the cell does translation occur?

Answer 28

cytoplasm

Question 29

At which carbon are the phosphates attached in ATP?

Answer 29

C5