True of the following is/are-
**Core Concept**
The question pertains to the mechanism of action of beta-lactam antibiotics, particularly their interaction with bacterial cell wall synthesis.
**Why the Correct Answer is Right**
Beta-lactam antibiotics, such as penicillins and cephalosporins, inhibit bacterial cell wall synthesis by binding to and inactivating penicillin-binding proteins (PBPs). These enzymes are essential for the cross-linking of peptidoglycan layers in the bacterial cell wall. By inhibiting PBPs, beta-lactams prevent the formation of a stable cell wall, ultimately leading to cell lysis and death. This mechanism is specific to bacterial cell walls, which are composed of peptidoglycan, and does not affect mammalian cells.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it is not related to the mechanism of action of beta-lactam antibiotics.
**Option B:** This option is incorrect because it refers to a different class of antibiotics, the tetracyclines, which inhibit protein synthesis rather than cell wall synthesis.
**Option C:** This option is incorrect because it is a side effect of beta-lactam antibiotics, not a mechanism of action.
**Clinical Pearl / High-Yield Fact**
It is essential to note that beta-lactam antibiotics are ineffective against bacteria that lack a functional cell wall, such as Mycoplasma species. This is a classic exam trap, as students may assume that all antibiotics will be effective against all types of bacteria.
**Correct Answer: C. Cell wall synthesis inhibition is the mechanism of action of beta-lactam antibiotics.**