Nucleic acids

Question 1

What are nucleic acids?

Answer 1

Molecules found in a cell’s nucleus.

Question 2

What are the two types of nucleic acid?

Answer 2

DNA and RNA

Question 3

What elements are present in nucleic acids?

Answer 3

Carbon, hydrogen, oxygen, nitrogen and phosphorus.

Question 4

What are the monomer units of nucleic acids called?

Answer 4

Nucleotides

Question 5

What three components make up a nucleotide?

Answer 5

A sugar
A phosphate group
A base

Question 6

What bond holds two nucleotides together?

Answer 6

Phosphodiester bond

Question 7

Name the sugar in

1) DNA
2) RNA

Answer 7

1) deoxyribose

2) ribose

Question 8

What 4 bases are present in DNA?

Answer 8

Adenine, Thymine, Cytosine and Guanine

Question 9

What 4 bases are present in RNA?

Answer 9

Adenine, Uracil, Cytosine and Guanine

Question 10

Which, out of pyrimidines and purines, is the smaller bases?

Answer 10

Pyrimidines.

Question 11

Which bases are purines?

Answer 11

Adenine and Guanine

Question 12

How many hydrogen bonds form between;

1) Adenine and Thymine
2) Guanine and Cytosine

Answer 12

1) 2 hydrogen bonds

2) 3 hydrogen bonds

Question 13

The bases are________to eachother. Complete the sentence.

Answer 13

Complementary

Question 14

True or false?

Purines always pair with purines.

Answer 14

False. Purines always pair with Pyrimidines.

Question 15

DNA is too big to leave the nucleus for proteins to be made in the cytoplasm. So what is done?

Answer 15

Information is copied into RNA, which is small enough to leave the nucleus.

Question 16

True or false?

1) DNA is a double helix
2) RNA contains Thymine
3) RNA is single stranded
4) DNA has an equal amount of A,T and C,G

Answer 16

1) True
2) False
3) True
4) True

Question 17

Put these steps for DNA Extraction in the right order.
A) Add a layer of ethanol on top so that the DNA precipitates out.
B) Mix with detergent to break cell membranes and release content.
C) Spool out white strands of DNA that form between ethanol and sample
D) Grind sample in mortar and pestle to break the cell walls
E) Add salt to break hydrogen bonds between DNA and water
F) Add protease enzyme to break down proteins in the nucleus.

Answer 17

1) D
2) B
3) E
4) F
5) A
6) C

Question 18

What is ribose/deoxyribose?

Answer 18

A pentose monosaccharide

Question 19

How is a phosphodiester bond broken?

Answer 19

Hydrolysis reaction. By adding water.

Question 20

How are nucleotides linked to form polynucleotides?

Answer 20

In condensation reactions. They are linked by phosphodiester bonds.

Question 21

What is the backbone called in a strand of DNA/RNA?

Answer 21

Sugar-phosphate backbone.

Question 22

The 2 strands in DNA are anti parallel. What does this mean?

Answer 22

They run in opposite directions.

Question 23

After proteins synthesis, what happens to the RNA molecule?

Answer 23

It is degraded and hydrolysed to be reused again.