Question

Following representations P, Q, and R denote few steps of Griffith Experiment. Identify the correct one(s).
P. R strain → Inject into mice → Mice die
Q. S strain (Heat killed) → Inject into mice → Mice die
R. R strain → Inject into mice → Mice live

• A. P only
• B. R only
• C. P and R
• D. Q and R

Hint:

Griffith’s experiment laid the foundation for the discovery of DNA as the genetic material.

Answer 1

The Correct Option is B

Griffith's experiment demonstrated bacterial transformation. The correct representations are:

P. R strain → Inject into mice → Mice die - Incorrect: The non-virulent R strain alone cannot kill mice.

Q. S strain (Heat killed) → Injected into mice → Mice die - Incorrect: Heat-killed S strain alone cannot kill mice.

R. R strain → Inject into mice → Mice live - Correct: This was Griffith's control experiment showing R strain is non-lethal.

The correct answer is (B) R only, as this was the only completely accurate representation among the options given.

Answer 2

Griffith's experiment showed that bacteria can undergo transformation. The accurate representations are:

P. R strain → Inject into mice → Mice die – Incorrect: The harmless R strain alone does not kill mice.

Q. S strain (Heat-killed) → Inject into mice → Mice die – Incorrect: Heat-killed S strain alone is not lethal to mice.

R. R strain → Inject into mice → Mice live – Correct: This was Griffith's control, proving the R strain is non-lethal.

The correct answer is (B) R only, as this was the only fully accurate option provided.