Condensation and Hydrolysis Reactions

Part A

Which polymers are composed of amino acids?

	Monomers
	Carbohydrates
	Proteins
	Nucleic acids

Correct

Proteins are composed of amino acids joined together.

Part B

Which of the following is not attached to the central carbon atom in an amino acid?

	A side chain (“R group”)
	An oxygen
	A carboxyl functional group
	An amino functional group

Correct

The central carbon atom in an amino acid is bonded to an amino functional group, a carboxyl functional group, a side chain, and hydrogen.

Part C

Which part of an amino acid is always acidic?

	Side chain (“R group”)
	Carboxyl functional group
	None of the above
	Amino functional group

Correct

The carboxyl group (COOH) contains two oxygen atoms that tend to pull electrons away from the hydrogen atom, so this group tends to lose a proton and is acidic.

Part D

Which monomers make up RNA?

	Polymers
	Simple sugars
	Amino acids
	Nucleotides

Correct

Nucleotide monomers make up nucleic acids.

Part E

Which of the following statements about the formation of polypeptides from amino acids is true?

	The reaction occurs through the addition of a water molecule to the amino acids.
	A bond can form between any carbon and nitrogen atom in the two amino acids being joined.
	A bond forms between the carboxyl functional group of one amino acid and the amino functional group of the other amino acid.
	Polypeptides form by condensation or hydrolysis reactions.

Correct

A hydroxyl group is removed from the carboxyl group of one amino acid and hydrogen is removed from the amino group of the other amino acid, allowing a bond to form between the two groups.

Part F

True or false? Enzymes in the digestive tract catalyze hydrolysis reactions.