AP BIOLOGY

Detailed explanation-1: -It consists of water, urea (from amino acid metabolism), inorganic salts, creatinine, ammonia, and pigmented products of blood breakdown, one of which (urochrome) gives urine its typically yellowish colour.

Detailed explanation-2: -Urine has large amounts of nitrogen, phosphorus, and potassium. Nitrogen content in urine is high, mostly in urea, which makes up more than 50 percent of the total organic acids. This includes urea from protein metabolism, sodium and potassium both of which come from food.

Detailed explanation-3: -Urea (also known as carbamide) is a waste product of many living organisms, and is the major organic component of human urine. This is because it is at the end of chain of reactions which break down the amino acids that make up proteins.

Detailed explanation-4: -The process of excretion is called urination and it is excreted through the urethra. Urine primarily consists of water (95%), including organic solute like urea (2.5%), and other wastes (2.5%) such as enzymes, hormones, fatty acids etc. Hence the statement is incorrect.

Detailed explanation-5: -(yoo-REE-uh) A substance formed by the breakdown of protein in the liver. The kidneys filter urea out of the blood and into the urine. Urea can also be made in the laboratory.