Question

sugars are a type of ______. they are produced by plants and release energy when they are broken down into smaller molecules.
a. carbohydrate
b. lipid
c. protein
d. hydrocarbon

Explanation:

To solve this, we recall the definitions of each biological macromolecule:

• Option A (carbohydrate): Carbohydrates include sugars (monosaccharides), starches, and fibers. Plants produce sugars (like glucose) through photosynthesis, and sugars release energy when broken down (e.g., cellular respiration).
• Option B (lipid): Lipids are fats, oils, etc., and do not include sugars.
• Option C (protein): Proteins are made of amino acids, not sugars.
• Option D (hydrocarbon): Hydrocarbons are compounds of hydrogen and carbon (e.g., fossil fuels), not related to sugars produced by plants for energy.

So sugars are a type of carbohydrate.

Answer:

A. carbohydrate