Module 1

Question 1

Which prime do mRNA strand run?

Answer 1

5’ to 3’

Question 2

Which way do tRNA run?

Answer 2

3’ to 5’

Question 3

How does a protein get made?

Answer 3

Ribosomes attach to mRNA, tRNA attaches at the anticodon to the specific codon associated with codon. Once this occurs, the next tRNA attaches to the next codon, the codon at the other end both join starting the protein.

Question 4

How does a tRNA gain its codons for protein synthesis (opposite end of anticodon)?

Answer 4

A protein attaches and adds it

Question 5

What ways do mRNA and tRNA run when together?

Answer 5

mRNA 5’-3’ and tRNA 3’ to 5’

Question 6

What experiment found the codon sequences and steps?

Answer 6

Cell-free in vitro protein synthesis.
Steps: Grind cells, centrifuge, collect cell lysate, add Dnase, add synthetic RNA.

Question 7

What is the start codons?

Answer 7

Aug codes for MET

Question 8

What is the wobble hypothesis?

Answer 8

That tRNA can code for more then one RNA

Question 9

What is the reading frame?

Answer 9

No start codon

Question 10

What is an open reading frame?

Answer 10

Starts with a start codon

Question 11

What is spontaneous mutation?

Answer 11

Errors in proofreading

Question 12

What are induced mutations?

Answer 12

From mutations (e.g. UV)

Question 13

What are germinal mutations?

Answer 13

Occur in germ line cells

Question 14

Does mutation occur before or after environmental change and how do we know?

Answer 14

Before, experimenting with bacteria colonies, breeding on plates without something moved to without (needed to grow) and colonies grow. Mutations were always present.

Question 15

What are stationary phase mutations?

Answer 15

They occur when populations of bacteria or fungi stop growing

Question 16

What are isolalles?

Answer 16

No effect on phentype type.

Question 17

Null alleles?

Answer 17

No gene products

Question 18

Neutral mutations?

Answer 18

No affect phentypes

Question 19

What is recessive suppressor-sensitive mutations?

Answer 19

Only visible when the second genetic factor is present.

Question 20

What is a natural mutation?

Answer 20

Amino acid substitution results in no effect

Question 21

What is a Missense mutation?

Answer 21

Amino acid substitution results in protein being defective

Question 22

What is a nonsense mutation?

Answer 22

Amino acid substitution results in STOP codon

Question 23

What happens to future generations if a tautomeric shift occurs?

Answer 23

During the 3rd generation, 1/4 children have the mutation still while the other are normal.

Question 24

What causes tautomeric shift?

Answer 24

Change in location of hydrogen base

Question 25

How do suppressor mutations revert back to their original form?

Answer 25

Change in the codon, second change in codon that turns the amino acid back to the start

Question 26

What is an intragenic mutation?

Answer 26

Point mutation that occurs in same gene but different codon

Question 27

What test is used to determine a mutation?

Answer 27

Ames Test

Question 28

How do we test for chemicals that cause mutations?\

Answer 28

Different chemicals are added along with protein to a plate lacking a certain thing.

Question 29

How do thymine dimers repair DNA replication?

Answer 29

Thymine dimers block replication in template strand, DNA polymerase lll restarts leaving gaps, RecA fills gaps and DNA lignase seals.

Question 30

How does mismatch repair in E.coli?

Answer 30

Muts recognises mismatch, MutH and MutL join complex, DNA ploymerase lll fills gaps and DNA ligase seals.

Question 31

Learn Holliday model