Question

1. milk contains a high concentration of the carbohydrate lactose. what is the basic building block of lactose?

a two monosaccharides joined together
b a chain of amino acids in a helix shape
c two fatty acids joined to a phosphate group
d a chain of alternating sugar and phosphate groups

Explanation:

Lactose is a disaccharide, and disaccharides are formed by the joining of two monosaccharides. Option A describes two monosaccharides joined together, which matches the structure of lactose (formed from glucose and galactose, both monosaccharides). Option B describes a protein (amino acid chain), Option C describes a lipid structure, and Option D describes a nucleic acid structure.

Answer:

A. Two monosaccharides joined together