The disorder caused by the deficiency of the enzyme phenylalanine hydroxylase is: MCQ with Answer and Explanation

Explanation:
Natural killer (NK) cells were discovered in the 1970s by Rolf Kiessling and others. They are part of innate immunity, killing virus-infected and tumor cells.

Explanation:
Gastrin is a peptide hormone produced by the G cells (gastrin cells) located in the pyloric antrum of the stomach. Its primary function is to stimulate the parietal cells of the gastric glands to secrete hydrochloric acid (HCl) and the chief cells to secrete pepsinogen. This prepares the stomach for the digestion of food. Gastrin also stimulates gastric motility and growth of the gastric mucosa. Secretin and CCK stimulate the pancreas and gall bladder.

Explanation:
Marshall and Warren discovered H. pylori in 1982 and proved it causes peptic ulcers, earning the 2005 Nobel Prize. Koch discovered TB, Pasteur vaccines, Fleming penicillin.