Griffith's Experiment

Q. In Griffith's experiment, which of the following resulted in the death of the mice?

1. Live S-strain bacteria $\to$ Injected into mice
2. Live R-strain bacteria $\to$ Injected into mice
3. Heat-killed S-strain bacteria$\to$ Injected into mice
4. Heat-killed R-strain bacteria $\to$ Injected into mice

Q.

In Griffith’s transformation experiment, the conversion of R strain to S strain was due to:

1. Uptake of naked DNA from medium by heat-killed S strains
2. Transfer of transforming principle from live R strain to heat-killed S strain bacteria
3. Transfer of transforming principle from heat-killed S strains to live R strains
4. Uptake of transforming principle from medium by heat-killed S strains to become live S strains.

Q.

The main reason for the virulent nature of the S strain of Streptococcus pneumoniae is the presence of:

1. Pili on cell envelope

2. Mesosome

3. Polysaccharide capsule

4. Lipoprotein cell membrane

Q.

What was Griffith hypothesis?

Q. Transformation experiments in bacteria were first performed by

1. MacLeod
2. Griffith
3. Pasteur
4. Meselson and Stahl

Q. The unequivocal proof that DNA is the genetic material came from experiments conducted by
[1 mark]

1. Hershey and Chase
2. Frederick Griffith
3. Watson and Crick
4. Meselson and Stahl

Q. Transformation experiments in bacteria were first performed by

1. MacLeod
2. Meselson and Stahl
3. Griffith
4. Pasteur

Q.

Name the bacteria responsible for pneumonia in humans.

Q.

What happens during transformation in Pneumococcus bacteria?

Q.

Which of the following is a mismatch?

1. Live R strain - Non-virulent

2. Heat-killed R strain - Virulent

3. Live S strain - Pathogenic

4. Heat-killed S strain - Non-pathogenic

Q. Who discovered malaria parasite?

1. Sir Ronald Ross
2. Charles Laveran
3. Patrick Manson
4. Grassi

Q. To describe transforming principle, Frederick Griffith performed series of experiments by selecting two strains of Streptococcus pneumoniae namely S-strain (virulent) and R-strain (non-virulent).
Which of the following steps does not describe this experiment?
[0.7 mark]

1. S-strain live $\stackrel{Injectedintomice}{\to }$Mice die
2. S-strain (heat-killed) + R-strain (live)$\stackrel{Injectedintomice}{\to }$Mice die
3. R-strain (heat-killed) + S-strain (live)$\stackrel{Injectedintomice}{\to }$Mice live
4. S-strain (heat-killed)$\stackrel{Injectedintomice}{\to }$Mice live

Q. In Griffith's experiment, which of the following resulted in the death of the mice?

1. Live S-strain bacteria $\to$ Injected into mice
2. Live R-strain bacteria $\to$ Injected into mice
3. Heat-killed S-strain bacteria$\to$ Injected into mice
4. Heat-killed R-strain bacteria $\to$ Injected into mice

Q.

Which of the following pathogens cause the disease pneumonia?

1. Salmonella typhi

2. S strain of Streptococcus pneumoniae

3. S and R strains of Streptococcus pneumoniae

4. Plasmodium vivax

Q.

The main reason for the virulent nature of the S strain of Streptococcus pneumoniae is the presence of:

1. Polysaccharide capsule

2. Lipoprotein cell membrane

3. Mesosome

4. Pili on cell envelope

Q. Which one of the following organisms is NOT used as biocontrol agent?

1. Trichoderma viride
2. Bacillus thuringiensis
3. Bacillus sphaericus
4. Bacillus subtilis

Q. In Griffith’s transformation experiment, the conversion of R strain to S strain was due to:

1. Transfer of transforming principle from live R strain to heat-killed S strain bacteria
2. Uptake of naked DNA from medium by heat-killed S strains
3. Transfer of transforming principle from heat-killed S strains to live R strains
4. Uptake of transforming principle from medium by heat-killed S strains to become live S strains.

Q.

Match the following:

Column 1	Column 2
Rhizobium	Antibiotic
Lactobacillus	Soil fertility
Penicillium	Vaccine
Rabies	Curdling

Q. Transduction was discovered in bacteria by

1. Wallace and Jacob
2. Lederberg and Tatum
3. Zinder and Lederberg
4. Herelle and Twort

Q. (a) In an experiment Griffith introduced heat-killed S-strain bacteria Streptococcus into a mouse along with live R-strain bacteria. The mouse died but the scientist recovered living S-strain bacteria from the dead mouse. Explain the conclusion Griffith arrived at after the experiment.
(b) Explain MacLeod, McCarty and Averys work that followed Griffith's experiment. State the conclusion they arrived at.

Q. (a) Explain the experiment performed by Griffith on Streptococcus pneumoniae. What did he conclude from this experiment?
(b) Name the three scientists who followed up Griffiths experiments.
(c) What did they conclude and how?

Q. Describe the experiment performed by Griffith. What conclusions did he infer from his observations?

Q.

what is the difference b/w type3 S strain heat killed type 3 S strain

Q. Frederick Griffith accidentally discovered transformation while attempting to
develop a vaccine for pneumonia. He injected mice with samples from S-strain
(virulent) and/or R-strain (non-virulent) pneumococcal bacteria (Streptococcus
pneumoniae). Which of the following results is NOT consistent with Griffith's
experiments?

1. Injected S-strain: Mouse dies
2. Injected R-strain: Mouse lives
3. Injected heat-killed S-strain: Mouse lives
4. Injected mixture of heat-killed S-strain and live R strain: Mouse lives

Q. In Griffith's experiment, the conversion of R-type to S-type of Diplococcus Pneumoniae when mixed with heat-killed S-type is called

1. Mutation
2. Transduction
3. Transformation
4. Transfection

Q. How did Louis Pasteur successfully demolish the popular theory of spontaneous generation ?

Q. Fill in the blanks with approprite words.
The change in DNA of a bacterium by incorporation of DNA fragment released by another bacterium is called ..........

Q. What is transformation?

Q. Analyse the given diagram which shows steps involved in the procedure of selecting transformed bacteria.
* In replica plating, a sterile pad is pressed on to plate M and then on the sterile agar in plate N.Identify the bacterial colony which has undergone transformation?

1. Colony 5
2. Colony 4
3. Colony 2
4. Colony 3

Q. Match the names of scientists given in Column A with the discovery made by them given in Column B.

	Column A		Column B
a)	Louis Pasteur	i)	Penicillin
b)	Robert Koch	ii)	Anthrax bacterium
c)	Edward Jenner	iii)	Fermentation
d)	Alexander Fleming	iv)	Small pox vaccine
		v)	Typhoid