Biomolecules

In most people, most of their food energy usually comes from

• carbohydrates

• proteins.

• lipids

• cellulose

Which of the following are structural components of monosaccharides?

• hydroxyl groups

• rings containing carbon

• carbon, hydrogen, and oxygen

• All of the above

The sweetest naturally occurring sugar, fructose, is a

• monosaccharide.

• disaccharide

• polysaccharide

• protein

What type of reaction is the breakdown of polysaccharides to form monosaccharides?

• hydrolysis

• condensation

• substitution

• substitution

Cholesterol is an example of a(n)

• monosaccharide

• polysaccharide

• lipid

• enzyme

Which elements are contained in all protein molecules?

• carbon, nitrogen, and oxygen

• carbon, sulfur, and oxygen

• carbon, nitrogen, and sulfur

• carbon, nitrogen, and iron

The characteristic functional groups of a protein are

• -OH and -NH₂

• -COOH and -CH₂

• -COOH and -NH₂

• -COOH and -SH

The symbol -R in the structural formula of an amino acid represents

• a metal

• a side chain

• a monosaccharide

• a disaccharide

Which of the following is a product of the reaction of two amino acids to form a dipeptide?

• ammonia

• nitrogen

• water

• oxygen

The unique characteristic of the amino acid cysteine is

• a high level of acidity.

• its ability to form hydrogen bonds with other amino acids.

• its ability to form a chemical bond with another cysteine.

• a second amino group