NEET BIOLOGY

Detailed explanation-1: -Proteins, carbohydrates and lipids are made from three basic molecules: carbon, hydrogen and oxygen. However, all proteins contain an element not found in carbohydrates and lipids is nitrogen.

Detailed explanation-2: -Amino acids contain at least one nitrogen (amino) atom, which makes them different from carbohydrates. However, some carbohydrates like glucosamine and mucopolysaccharides do contain nitrogen atoms. The carbohydrates might have a nitrogen atom, but amino acids and proteins always have nitrogen atoms.

Detailed explanation-3: -Carbohydrates and lipids are made of only carbon, hydrogen, and oxygen (CHO). Proteins are made of carbon, hydrogen, oxygen, and nitrogen (CHON). Nucleic acids such as DNA and RNA contain carbon, hydrogen, oxygen, nitrogen, and phosphorus (CHON P).

Detailed explanation-4: -Lipids are composed mainly of carbon and hydrogen, but they can also contain oxygen, nitrogen, sulfur, and phosphorous.

Detailed explanation-5: -Answer and Explanation: Nitrogen is not present in fats and carbohydrates. Fats and carbohydrates contain carbon, hydrogen and oxygen atoms. Proteins contain nitrogen and smaller amounts of carbon and hydrogen atoms.