Replication of DNA

Question 1

What carries the genetic instructions necessary for cell function?

Answer 1

DNA

DNA is essential for the replication and functioning of new cells.

Question 2

What is the process of copying the DNA molecule called?

Answer 2

Replication

Replication occurs during mitosis and meiosis.

Question 3

Describe the nature of DNA replication.

Answer 3

Semi-conservative

Each new DNA molecule contains one original strand and one new strand.

Question 4

What enzyme breaks the hydrogen bonds between base pairs during DNA replication?

Answer 4

Helicase

Helicase causes the DNA molecule to unzip and unwind.

Question 5

What are the sites called where replication and separation occur?

Answer 5

Replication forks

These forks indicate areas of active DNA replication.

Question 6

What serves as the starting point of DNA replication?

Answer 6

RNA primer

The primer is formed with the help of the enzyme primase.

Question 7

Which enzyme helps attach new nucleotides during DNA replication?

Answer 7

DNA Polymerase

DNA Polymerase attaches nucleotides only to the 3 prime end of the original strand.

Question 8

In which direction does DNA replication occur?

Answer 8

5 prime to 3 prime

This directional replication results in a leading strand and a lagging strand.

Question 9

What is the continuous new strand formed during DNA replication called?

Answer 9

Leading strand

The leading strand elongates continuously as DNA unzips.

Question 10

What are the short sections of DNA formed opposite the direction of unzipping called?

Answer 10

Okazaki fragments

These fragments are formed on the lagging strand.

Question 11

What does DNA Polymerase do to the RNA primers during replication?

Answer 11

Disassembles and replaces them with DNA nucleotides

This proofreading function ensures correct base pairings.

Question 12

What enzyme joins the Okazaki fragments together?

Answer 12

Ligase

Ligase is essential for completing the lagging strand.

Question 13

What happens to the new strands after they are formed?

Answer 13

They rewind into the double helix structure

This results in the formation of a complete DNA molecule.

Question 14

What is the ‘end of replication problem’?

Answer 14

The new daughter strands become slightly shorter due to primer removal

This issue arises because primers can’t be replaced by nucleotides.

Question 15

What structure is placed on the ends of DNA to solve the ‘end of replication problem’?

Answer 15

Telomere

Telomeres protect the ends from damage and do not code for proteins.

Question 16

True or False: Telomeres code for proteins.

Answer 16

False

Telomeres do not code for any protein, preventing severe consequences when lost.