Quiz 12 - 15th of November

Question 1

How many strains of streptococcus are there and describe them

Answer 1

• there are 2 strains of Streptococcus:- S strain is virulent- R strain is nonvirulent

Question 2

Who studied streptococcus and in what year did they study streptococcus

Answer 2

Frederick Griffith, 1928 studied Streptococcus pneumoniae,
a pathogenic bacterium causing pneumonia

Question 3

What animals did Griffith test to understand the difference within the 2 strains

Answer 3

Mice

Question 4

What were Griffiths results

Answer 4

Griffith’s results:- live S strain cells killed the mice- live R strain cells did not kill the mice- heat-killed S strain cells did not kill the mice- heat-killed S strain + live R strain cells killed the mice

Question 5

What is Griffiths conclusion

Answer 5

Griffith’s conclusion:- information specifying virulence passed from the dead S strain cells into the live R strain cells- Griffith called the transfer of this information transformation

Question 6

In 1944 Avery, MacLeod, & McCarty, repeated Griffith’s experiment using purified cell extracts. What did they discover

Answer 6

• removal of all protein from the transforming material did not destroy its ability to transform R strain cells- DNA-digesting enzymes destroyed all transforming ability

Question 7

What is the transforming material

Answer 7

DNA

Question 8

What does DNA stand for and what is it made of

Answer 8

Stands for Deoxyribonucleic acid
Made up of subunits called
Nucleotides
which are made of:

Phosphate group
5 carbon sugar
Nitrogenous base

Question 9

Are nucleotides connected in short or long chains and what orientation do they have

Answer 9

Nucleotides are connected to each other to form a long chain
The chain of nucleotides has a 5’ to 3’ orientation

Question 10

What bond do nucleotides have

Answer 10

phosphodiester bond: bond between adjacent
nucleotides
* formed between the phosphate group of one
nucleotide and the 3’ –OH of the next nucleotide