Module Two, Lecture Twelve

Question 1

What is DNA Synthesis?

Answer 1

The process where a new strand of DNA is created using an existing DNA template. Both DNA strands are used as template strands in DNA replication

Question 2

What is the Purpose of DNA Synthesis?

Answer 2

DNA synthesis ensures that each new cell formed during cell division contains a complete set of genetic instructions

Question 3

What is DNA Synthesis crucial for? ( 4 )

Answer 3

1. Cell division
2. DNA repair
3. Genetic replication
4. Artificial DNA synthesis, allowing scientists to create DNA molecules of virtually any sequence

Question 4

What are the Phases of DNA Synthesis? ( 4 )

Answer 4

1. Helicase
2. DNA Polymerase
3. Primase
4. Ligase

Question 5

What is the purpose of the Helicase “The Unzipping Enzyme”? ( 2 )

Answer 5

1. Uses ATP hydrolysis to separate double-stranded DNA or RNA into single strands
2. It breaks through the hydrogen bonds that hold the DNA bases together

Question 6

What is the purpose of DNA Polymerase “The Builder Enzyme”? ( 2 )

Answer 6

1. Replicates DNA molecules to build a new strand of DNA
2. Only builds a new strand in the 5’ - 3’ direction ( leading strand )

Question 7

What is the purpose of the Primase “The Initialiser”? ( 1 )

Answer 7

1. Makes the primer for DNA Polymerase to figure out where to build a new DNA strand

Question 8

What is the purpose of the Ligase “The Gluer”? ( 1 )

Answer 8

1. Pieces DNA fragments together

Question 9

When can DNA errors be repaired? ( 2 )

Answer 9

1. During Replication using EXOnuclease
2. After Replication using Endonuclease

Question 10

What is the importance of correcting DNA Errors? ( 3 )

Answer 10

1. If not corrected, the DNA error becomes part of the DNA template
2. Permanent DNA change
3. E.g. DNA damage / Mutation