Which organic molecules are composed of a nitrogenous base, a monosaccharide, and a phosphate group?

• A. Nucleotides
• B. Fatty acids
• C. Monosaccharides
• D. Amino acids

Answer: (A)

Verified step by step guidance

1. Step 1: Begin by analyzing the components mentioned in the problem: nitrogenous base, monosaccharide, and phosphate group. These are key structural elements of certain organic molecules.
2. Step 2: Recall the structure of nucleotides. Nucleotides are composed of three parts: a nitrogenous base (such as adenine, guanine, cytosine, thymine, or uracil), a monosaccharide (specifically a pentose sugar like ribose or deoxyribose), and a phosphate group.
3. Step 3: Compare the structures of the other options provided (Fatty acids, Monosaccharides, and Amino acids) to the components listed in the problem. Fatty acids consist of a hydrocarbon chain and a carboxyl group, monosaccharides are simple sugars, and amino acids contain an amino group, a carboxyl group, and a side chain.
4. Step 4: Eliminate the options that do not match the structural components described in the problem. Fatty acids, monosaccharides, and amino acids do not contain all three components (nitrogenous base, monosaccharide, and phosphate group).
5. Step 5: Conclude that nucleotides are the correct answer, as they are the only organic molecules composed of a nitrogenous base, a monosaccharide, and a phosphate group.