bacterial genetics

?
  • Created by: Jess
  • Created on: 16-05-13 12:46
What are the three mechanisms for genetic transfer?
Transformation, Conjugation and Transduction
1 of 14
What is Transformation?
The transfer of genetic material as free DNA to recipient cells, with no direct contribution from the intact donor bacterium.
2 of 14
What is Conjugation?
A mechanism of gene transfer that depends on the presence of a conjugative plasmid in the donor organism and involves cell-tocell contact between donor and recipient bacteria.
3 of 14
What is Transduction?
The transfer of donor bacterial genetic material to recipient cells by a defective bacteriophage particle.
4 of 14
What is a Plasmid?
Autonomous, independently replicating genetic elements that usually confer additional phenotypes on the bacteria that harbour them.
5 of 14
How do bacteria protect their own DNA from their restriction enzymes?
They modify it usually by methylation within the recognition sequence.
6 of 14
What sites to restriction enzymes recognise?
Specific symmetrical sequences in DNA, usually palindromes, that are 4 to 6 base pairs long.
7 of 14
Bacteria show clonal growth, what does that mean?
All cells in a bacterial colony are genetically identical. The same is true of a plaque.
8 of 14
What are the advantages of studying genes in bacteria instead of eukaryotes?
It is simple, cheap and quick.
9 of 14
What is a clone?
A groupof individuals derived by a vegetative (non-sexual) process from a single individual.
10 of 14
How does conjugal DNA transfer occur?
By rolling circle replication. The gene traZ encodes an endonuclease which makes a nick in the plasmid DNA at a site called oriT (origin of transfer).
11 of 14
What can you deduce if two genes are consistently co-transformed?
That they are so close together on the chromosome that they are highly likely to remain together during random fragmentation of DNA. (co-transformation indicates close genetic linkage)
12 of 14
What are the main types of bacterial mutants?
Nutirtional mutants, Resistance mutants and Conditional lethal mutants.
13 of 14
What is a merodiploid?
A bacterium that contains its own entire chromosome plus a part of the chromosome of a donor cell.
14 of 14

Other cards in this set

Card 2

Front

What is Transformation?

Back

The transfer of genetic material as free DNA to recipient cells, with no direct contribution from the intact donor bacterium.

Card 3

Front

What is Conjugation?

Back

Preview of the front of card 3

Card 4

Front

What is Transduction?

Back

Preview of the front of card 4

Card 5

Front

What is a Plasmid?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »