DNA- Experiments

Question 1

What is the genome?

Answer 1

Total genetic material of cell organism or virus
String of 1D information in sequence of a chemical polymer
Collection of genes

Question 2

What are genes?

Answer 2

Genes are made up of DNA- act as instructions to make proteins and RNA

Question 3

Describe the properties of the genome

Answer 3

Chemically stable
Accurate mechanism for replication
Mechanism for decoding
Capable of evolution

Question 4

What did the DNA experiments prove?

Answer 4

That DNA is the genetic material

Question 5

Describe the properties of the S and R form of Streptococcus pneumonaie

Answer 5

Exist as deadly S form and harmless R form
S form- surrounded by polysaccharide capsule- forms smooth colonies
R form- no capsule- forms rough colonies

Question 6

Describe what happened in Griffith experiment

Answer 6

Used a mouse- living R cells were transformed to living S cells in the presence of dead S cells
Living S cells killed mouse
Dead S cells- mouse healthy
Living R cells mouse healthy
Dead S cells and living R cells- mouse dead
Living S cells found in mouse blood

Question 7

What is the difference between Avery, McCarty and MacLeod Experiment and the Griffith experiment?

Answer 7

Reproduce the R to S transformation without the mouse
Fractionated extracts from dead S form and added these to R cells
DNA was active compound
S cell gene is placed in R cell to transform it- transforming principle

Question 8

Describe the Hershey- Chase experiment

Answer 8

Used bacteriophage T2
Radioactively labelled protein part (35S) and DNA (32P) part of T2
Found 32P inside host cell which proves DNA is what is actually found inside cell
Infection of host with T2 turns it into virus factory and kills cell
Virus consists of protein coat- packages DNA
Shows DNA is what is responsible for coding virus