Bacterial Genetics

Question 1

What is natural selection?

Answer 1

A method of evolution

Question 2

What is spontaneous mutation?

Answer 2

Base substitution (point mutation)

Question 3

What is missense mutation?

Answer 3

Changes the base; ALWAYS changes the protein

Question 4

What is nonsense mutation?

Answer 4

Stops the protein early where it’s not supposed to stop; Changes the DNA and RNA to an early STOP codon

Question 5

What is a silent mutation?

Answer 5

Change the DNA and RNA but the amino acid stays the same

Question 6

Which mutation adds/deletes nucleotides?

Answer 6

Frame shift mutation

Question 7

What are the radiation mutations?

Answer 7

UV light and ionizing

Question 8

What does UV light cause?

Answer 8

Thymine diner forming that distorts the DNA

Question 9

Although UV light doesn’t cause mutation what does it do?

Answer 9

When the body goes to repair it, it mispairs with the wrong bases

Question 10

What does ionizing do?

Answer 10

Causes the DNA to break in spots and causes it to mutate

Question 11

What new traits can genetic change add?

Answer 11

Mutations and gene transfer

Question 12

Are bacteria static or dynamic in the genes they can express during their lifespan?

Answer 12

Dynamic— 1) gene regulation

2) mutation
3) gene transfers

Question 13

What is base incorporation?

Answer 13

Where one wrong base is put into place

Question 14

How do you repair a base incorporation mutation

Answer 14

DNA polymerase proofreads & mismatch repair

Question 15

Name what happens in the steps for base incorporation repair

Answer 15

1) an enzyme cuts the strand with the wrong base & takes it out
2) DNA polymerase synthesizes a new strand & puts it in

Question 16

Name the repairs of thymine dimers

Answer 16

Light repair
Excision or dark repair
SOS repair

Question 17

What is SOS repair

Answer 17

It’s the emergency repair. It kicks in when you have lots of thymine dimers where the other systems are overwhelmed.
They try to replicate across the thymine dimers & repair but they can’t proofread

Question 18

What is genetic recombination

Answer 18

When you get DNA from 2 sources combing together in an organism & the product is called recombinants

Question 19

What can bacteria transfer

Answer 19

Chromosome segments: narrow host range

Plasmids

Question 20

If transfers occur, what does it need to be passed on to progeny

Answer 20

Origin of replication

Question 21

What is homologous recombination

Answer 21

Finds a similar area in the chromosome & it physically kicks out the original base & base pairs with the other strand; may give the cell new characteristics
HAVE to be similar species to do homologous recombination

Question 22

Can plasmids self replicate

Answer 22

Yes. & they can jump from one species to another

Question 23

Name the methods of transfer

Answer 23

Transformation
Transduction
Conjugation

Question 24

Describe Transformation

Answer 24

Transfer “NAKED” DNA to competent cells

Only 1 strand enters so not every cell is competent to begin with. Only 1 strand of DNA enters & other breaks down

Homologous recombination

Question 25

Where does the naked DNA come from

Answer 25

It’s dead bacteria floating in the environment from dead bacteria

Question 26

What is Transduction

Answer 26

BACTERIOPHAGES accidentally pick up bacterial DNA during replication & assembly

Transfer bacterial genes to new cells

Homologous recombination

Question 27

What is conjugation

Answer 27

BACTERIAL SEX