Phenylketonuria (PKU) is an example of: MCQ with Answer and Explanation

Explanation:
Viruses are non-living outside a host cell and must hijack a host's cellular machinery to replicate, making them obligate intracellular parasites. They contain either DNA or RNA, not both (except some rare cases). They lack cell walls and metabolic machinery. Their status as living or non-living is debated, but they are biologically active only inside a host.

Explanation:
Stanley Miller and Harold Urey (1953) simulated primitive Earth conditions by mixing methane, ammonia, hydrogen, and water vapor and providing electric discharge (simulating lightning). They obtained amino acids (glycine, alanine, etc.), supporting the chemical origin of life hypothesis. It didn't produce proteins, DNA, or lipids directly. This experiment was crucial for abiogenesis theories.

Explanation:
Pepsin is the primary proteolytic enzyme in the stomach, breaking down proteins into peptones. Trypsin is a pancreatic enzyme secreted by the pancreas, not the liver, which continues protein digestion in the small intestine. Bile, produced by the liver, emulsifies fats, but lipase (pancreatic lipase) actually digests (hydrolyzes) them into fatty acids and glycerol. Only statement 1 is correct.