The function of the myelin sheath is to: MCQ with Answer and Explanation

Explanation:
Penicillin and other beta-lactam antibiotics (cephalosporins, carbapenems) inhibit the transpeptidase enzyme involved in cross-linking peptidoglycan, weakening the cell wall and causing bacterial lysis. Tetracycline and streptomycin inhibit protein synthesis by acting on ribosomes. Chloramphenicol also inhibits protein synthesis. Penicillin is most effective against actively dividing gram-positive bacteria.

Explanation:
Ringworm (dermatophytosis) is a superficial fungal infection of the skin, hair, or nails. It is caused by dermatophyte fungi, primarily from the genera Microsporum, Trichophyton, and Epidermophyton. Despite the name, it is not caused by a worm. Aspergillus can cause aspergillosis, and Saccharomyces is yeast used in baking and brewing.

Explanation:
Mitochondria have two membranes (outer and inner) and are the site of Krebs cycle and oxidative phosphorylation. They possess 70S ribosomes, not 80S. Hence, statements 1 and 3 are correct.