Y12 MW - Nucleic Acids, Structure and Function (Complete)

Question 1

What are nucleotides made up of?

Answer 1

Phosphate group, pentose sugar and a nitrogen-containing organic base

Question 2

What are the components of a DNA nucleotide?

Answer 2

A phosphate group, deoxyribose and a nitrogen-containing organic base (Adenine, Thymine, Cytosine or Guanine)

Question 3

What does a condensation reaction between two nucleotides form?

Answer 3

A phosphodiester bond

Question 4

What is the structure of a DNA molecule?

Answer 4

A DNA molecule is a double helix with two polynucleotide chains held together by hydrogen bonds between specific complementary base pairs

Question 5

What is the structure of an RNA molecule?

Answer 5

An RNA molecule is a relatively short polynucleotide chain

Question 6

What are the components of an RNA nucleotide?

Answer 6

A phosphate group, ribose and an organic base (Adenine, Cytosine, Guanine and Uracil)

Question 7

What is the full name of DNA?

Answer 7

Deoxyribonucleic acid

Question 8

Which way do the two polynucleotide strands run in DNA?

Answer 8

Antiparallel

Question 9

DNA is an ——— molecule

Answer 9

Information

Question 10

Why are there weak hydrogen bonds between the two DNA strands?

Answer 10

So the DNA strands can be separated for DNA replication

Question 11

Why is DNA a double helix?

Answer 11

To protect the bases so they are not damaged

Question 12

Why is DNA a long molecule?

Answer 12

So it can store a lot of genetic information

Question 13

Why is DNA in the shape of a helix?

Answer 13

So it is compact

Question 14

Why does DNA have a phosphate-sugar backbone?

Answer 14

To provide strength for DNA

Question 15

Which of the four DNA bases are purines?

Answer 15

Adenine and Guanine

Question 16

Which of the four DNA bases are pyrimidines?

Answer 16

Thymine and Cytosine

Question 17

What two chemicals are found within chromosomes?

Answer 17

Histones and DNA

Question 18

Which two chemicals are found inside of a chromosome?

Answer 18

Histones and DNA

Question 19

How is DNA packaged in eukaryotic cells?

Answer 19

The DNA condenses (wraps around) histones (proteins)

Question 20

What kind of chemical are histones?

Answer 20

Proteins

Question 21

What does RNA stand for?

Answer 21

Ribose nucleic acid

Question 22

What are the differences between DNA and RNA?

Answer 22

The sugar present in RNA is called ribose while in DNA it is deoxyribose
In RNA the bases are Adenine, Uracil, Guanine and Cytosine while in DNA they are Adenine, Thymine, Guanine and Cytosine
RNA is single stranded while DNA is double stranded

Question 23

What are the three types of RNA?

Answer 23

mRNA, tRNA and rRNA

Question 24

What is a RNA nucleotide made up of?

Answer 24

A phosphate group, a ribose sugar and a base (Adenine, Uracil, Guanine or Cytosine)

Question 25

What two enzymes are involved in DNA replication?

Answer 25

DNA helicase and DNA polymerase

Question 26

What is the function of DNA helicase?

Answer 26

To catalyse the break down of the hydrogen bonds between the bases

Question 27

What is the process of DNA replication?

Answer 27

DNA helicase catalyses the break down of hydrogen bonds between the bases, separating the DNA strands Free nucleotides in the nucleoplasm become attracted to their complementary pairs Hydrogen bonds form between the complementary base pairs DNA polymerase catalyses the formation of phosphodiester bonds between the nucleotides Two identical strands are created, each made up of half of the original material (semi-conservative)

Question 28

What does it mean that DNA replication is semi-conservative?

Answer 28

Each of the two identical strands of DNA is made up of half of the original material

Question 29

What provided evidence that semi-conservative replication was the process of DNA replication?

Answer 29

The Meselson Stahl experiment

Question 30

What is the function of DNA polymerase?

Answer 30

An enzyme which joins nucleotides together with the formation of phosphodiester bonds

Question 31

What is the main role of DNA?

Answer 31

To carry the genetic code which are instructions for making proteins