Molecular Biology Techniques & Horizontal Gene Transfer

Question 1

Define Binary Fission

Answer 1

• How bacteria reporduce
• A form of asexual reproduction

Question 2

Why are daughter cells genetically identical to the parent?

Answer 2

Due to the process of mitosis, a type of cell division that ensures the accurate duplication and distribution of the parent cell’s genetic material

Question 3

Bacteria aquire genetic variation through: (2 options)

Answer 3

1. Mutation
2. Horizontal gene transfer (HGT)

Question 4

Define mutation

Answer 4

It is a permanent change in the nucleotide sequence which may create new cellular functionalities or lead to dysfucntion in existing properties

Question 5

Spontaneous mutation vs Induced mutation

Answer 5

Sponaneous mutation = Error during DNA replication
Induced mutation = Errors caused by exposure to mutagens like:
* UV light
* Radiation

Question 6

Define silence mutation

Answer 6

Change in nucleotide that does not result in change in amino acids

Question 7

Define Missense mutation

Answer 7

Change in nucleotide that does result in a change in amino acids

Question 8

Define Nonsense mutation

Answer 8

A ‘stop codon’ that was introduced, resulting in the termination of translation

Question 9

What is horizontal gene transfer (Lateral gene transfer)

Answer 9

The process by which an organism acquires DNA from another organism without being its offspring. This can occur between different species and is especially common among bacteria

Question 10

What are the 3 mechanisms of HGT

Answer 10

1. Transformation
2. Transduction
3. Conjugation

Question 11

Define Phages or Bacteriophages

Answer 11

Viruses that infect prokaryotic cells

Question 12

Define Transduction

Answer 12

It is the process where phages package bacterial DNA (chromosomal or plasmid) and transfer it to another bacterium

Question 13

Generalised transduction vs specialised transduction

Answer 13

Generalised transduction = Phages packages any DNA
Specialised transduction = Phage packages/ transfers specific sets of genes

Question 14

Define Transformation (HGT term)

Answer 14

The uptake of ‘foreign’ (exogenous) DNA and its subsequent
integration into the bacterial chromosome by homologous recombination;
the resulting cell is called a transformant