A glucose molecule is to starch as (Explain your answer.)
a. A steroid is to a lipid
b. A protein is to an amino acid
c. A nucleic acid is to a polypeptide
d. A nucleotide is to a nucleic acid

Verified step by step guidance

1. Step 1: Begin by understanding the relationship between glucose and starch. Glucose is a monosaccharide (simple sugar), while starch is a polysaccharide (complex carbohydrate) made up of many glucose molecules linked together. This relationship is one of a building block (glucose) forming a larger structure (starch).
2. Step 2: Analyze each answer choice to determine if it represents a similar 'building block to larger structure' relationship. For example, in option (a), a steroid is not a building block of lipids; rather, it is a type of lipid. This does not match the glucose-to-starch relationship.
3. Step 3: Evaluate option (b). Proteins are made up of amino acids, which are their building blocks. This is the reverse of the glucose-to-starch relationship, as amino acids are smaller units forming a larger structure (protein).
4. Step 4: Consider option (c). Nucleic acids are composed of nucleotides, not polypeptides. Polypeptides are chains of amino acids that form proteins, so this option does not match the glucose-to-starch relationship.
5. Step 5: Examine option (d). Nucleotides are the building blocks of nucleic acids, just as glucose is the building block of starch. This matches the relationship described in the problem, where smaller units combine to form a larger structure.

Key Concepts

Monomers and Polymers

Monomers are the basic building blocks of larger molecules known as polymers. In the context of carbohydrates, glucose is a monosaccharide (a simple sugar) that serves as a monomer, while starch is a polysaccharide (a complex carbohydrate) made up of many glucose units linked together. Understanding this relationship is crucial for analyzing how smaller units combine to form larger structures.

Biomolecules

Biomolecules are organic molecules that are essential for life, including carbohydrates, proteins, lipids, and nucleic acids. Each type of biomolecule has specific functions and structures. Recognizing the categories of biomolecules helps in understanding their roles in biological systems, such as how glucose (a carbohydrate) relates to starch (a carbohydrate polymer).

Analogous Relationships

Analogous relationships in biology refer to the comparison between two sets of items that share a similar function or structure but are different in composition. In this question, the relationship between glucose and starch is analogous to the relationships presented in the answer choices, where a smaller unit (monomer) relates to a larger unit (polymer) in each case. Identifying these analogies is key to selecting the correct answer.