Genetics

Question 1

Explain how pyrophosphate is produced, including bonds and enzymes

Answer 1

DNA polymerase catalyse formation of Phosphodiester bond (5/3)

Extra phosphate groups from activated base is released

Question 2

How is light produced for pyrosequencing?

Answer 2

Pyrophosphate used to form ATP, used to produce light

Question 3

How is DNA polymerase formed from its gene?

Answer 3

Transcription + Translation

Golgi apparatus fold / twist to form tertiary structure

Question 4

How is DNA polymerase used in sequencing?

Answer 4

Catalyse formation of Complementary strand

Question 5

What are the two methods for sequencing?

Answer 5

Fred Sanger’s method

Pyrosequencing

Question 6

What is a mutagen?

Answer 6

Something that increases rate of mutation

Question 7

What are physical agents in mutation?

Answer 7

X rays
Gamma rays
UV

Question 8

What are chemical agents for mutation?

Answer 8

Mustard gas
Nitrous acid
Aromatic amines
Reactive oxygens
Colchicine
Benzopyrene

Question 9

What are biological agents?

Answer 9

Some virus
Transponsons
Food contaminants

Question 10

What’s the difference between chromosome and DNA mutations?

Answer 10

Chromosome - Change in structure/ location of genes

• multiple genes
• larger impact
• somatic cells

DNA - change in base sequence

• single gene
• smaller change
• during meiosis

Question 11

What are the types of chromosome mutations

Answer 11

Deletion
Inversion
Translocation
Duplication
Non-disconjunction

Question 12

What causes DNA fragments to move across during electrophoresis?

Answer 12

Cathode and anode at each end of electrophoresis gel,

DNA has an overall negative charge due to phosphate groups

DNA moves to anode.

Question 13

What is the function of gyrase in pyrosequencing?

Answer 13

Removes Activated neucleotides so a different base can be added

Question 14

How do restriction enzymes cut a section of DNA?

Answer 14

At a specific Palindromic part of the DNA

Question 15

What is the purpose of PCR?

Answer 15

Amplify / increase number of DNA for analysis.

Question 16

What is the PCR process

Answer 16

Split Double helix by raising temp 94-96

Cool to 68, allow Primer to anneal

Taq DNA polymerase forms new chain ( with Mg as cofactor)

Question 17

In PCR, what is the cofactor needed?

Answer 17

Magnesium

Question 18

Why id Taq DNA polymerase needed and not just normal?

Answer 18

Taken from bacteria that live in high temperatures,

Enzyme doesnt denature during PCR

Question 19

How is PCR different to DNA polymerase?

Answer 19

Only short section
Need primer
Need heating and cooling

Question 20

What is tissue typing?

Answer 20

Analysising people’s DNA to see compatibility for transplantation.