Question

Assertion & Reason Type Questions :[2×1=2]In the following questions, a statement of Assertion (A) is followed by a statement of Reason (R). (1) Both (A) and (R) are true and (R) is the correct explanation of (A)(2) Both (A) and (R) are true but (R) is not the correct explanation of (A)(3) (A) is true but (R) is false (4) (A) is false but (R) is true 13.A : Symbol of silver and tin is Ag and Sn respectively.[1] R : Silver is a metal but tin is not a metal.14.A : The antibiotic penicillin blocks the bacterial processes that build the cell wall.[1] R : Penicillin cannot have such effect on humans as they have cell wall.

Answer 1

Answer:

13.(A) is true but (R) is false.

14.Both (A) and (R) are true and (R) is not the correct explanation of (A).

Explanation:

Penicillin is an antibiotic that blocks the cell wall biosynthesis by inhibiting the enzyme responsible for cross linking of peptodoglycan layer of the cell wall (enzyme is transpeptidase) in bacteria.

Since human cells do not contain a cell wall, penicillin treatment results in bacterial cell death without affecting human cells.