Which of the following is an excitatory neurotransmitter in the central nervous system? MCQ with Answer and Explanation

Explanation:
Lysozyme, an enzyme found in tears, saliva, and egg white, hydrolyzes the β-1,4-glycosidic bond between N-acetylmuramic acid and N-acetylglucosamine in peptidoglycan, weakening the bacterial cell wall and causing lysis. It is part of innate immunity. Penicillin inhibits peptidoglycan synthesis.

Explanation:
If two genes are completely linked, they are located very close together on the same chromosome and do not undergo independent assortment or crossing over. They are inherited together as a single unit. A dihybrid cross (RrYy x RrYy) with complete linkage behaves like a monohybrid cross. The F1 produces only parental gametes (RY and ry). The F2 generation will have a genotypic ratio of 1 RRYY : 2 RrYy : 1 rryy, resulting in a phenotypic ratio of 3:1.

Explanation:
Robert Koch established Koch's postulates, demonstrating that specific microbes cause specific diseases (anthrax, tuberculosis, cholera).