The scientist who proposed the 'indirect fit' model of enzyme action was: MCQ with Answer and Explanation

Explanation:
The liver uses the urea cycle (ornithine cycle) to convert highly toxic ammonia, produced from amino acid deamination, into less toxic urea, which is excreted by the kidneys. The kidneys filter urea but do not synthesize it. Pancreas is digestive/endocrine, intestine absorbs nutrients.

Explanation:
The ureters are two muscular tubes that propel urine from the renal pelvis of each kidney to the urinary bladder via peristaltic contractions. Urethra exits bladder, renal pelvis and calyces are within the kidney.

Explanation:
The domesticated silkworm, Bombyx mori, is a monophagous insect, meaning it feeds almost exclusively on the fresh leaves of the mulberry plant (primarily Morus alba). The quality and quantity of silk produced are directly dependent on the quality of the mulberry leaves consumed by the larvae. While tasar silkworms feed on oak and castor, the common mulberry silkworm requires Morus alba.