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Flashcards in Bacterial Genetics Deck (27)
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1

What is natural selection?

A method of evolution

2

What is spontaneous mutation?

Base substitution (point mutation)

3

What is missense mutation?

Changes the base; ALWAYS changes the protein

4

What is nonsense mutation?

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

5

What is a silent mutation?

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

6

Which mutation adds/deletes nucleotides?

Frame shift mutation

7

What are the radiation mutations?

UV light and ionizing

8

What does UV light cause?

Thymine diner forming that distorts the DNA

9

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

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

10

What does ionizing do?

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

11

What new traits can genetic change add?

Mutations and gene transfer

12

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

Dynamic--- 1) gene regulation
2) mutation
3) gene transfers

13

What is base incorporation?

Where one wrong base is put into place

14

How do you repair a base incorporation mutation

DNA polymerase proofreads & mismatch repair

15

Name what happens in the steps for base incorporation repair

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

16

Name the repairs of thymine dimers

Light repair
Excision or dark repair
SOS repair

17

What is SOS repair

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

18

What is genetic recombination

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

19

What can bacteria transfer

Chromosome segments: narrow host range
Plasmids

20

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

Origin of replication

21

What is homologous recombination

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

22

Can plasmids self replicate

Yes. & they can jump from one species to another

23

Name the methods of transfer

Transformation
Transduction
Conjugation

24

Describe Transformation

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

25

Where does the naked DNA come from

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

26

What is Transduction

BACTERIOPHAGES accidentally pick up bacterial DNA during replication & assembly

Transfer bacterial genes to new cells

Homologous recombination

27

What is conjugation

BACTERIAL SEX