Question 1

Which of the following statements about the secondary structure of proteins is TRUE?

Accepted Answer

The secondary structure includes alpha helices and beta sheets, which are stabilized by hydrogen bonds between backbone amide and carbonyl groups.

Question 2

Which of the following amino acids has a basic side chain at physiological pH?

Accepted Answer

Lysine

Question 3

A peptide bond forms between which two functional groups of adjacent amino acids?

Accepted Answer

The carboxyl group of one amino acid and the amino group of another amino acid

Question 4

Which of the following best describes the difference between the lock-and-key and induced fit models of enzyme catalysis?

Accepted Answer

The lock-and-key model suggests the enzyme and substrate fit perfectly without any change, while the induced fit model suggests the enzyme changes shape to accommodate the substrate.

Question 5

Which of the following is a competitive inhibitor of an enzyme?

Accepted Answer

A molecule that binds to the active site and prevents substrate binding

Question 6

Which of the following statements about glycogen is TRUE?

Accepted Answer

Glycogen is a branched polymer of glucose with both alpha(1→4) and alpha(1→6) glycosidic bonds.

Question 7

Which of the following is a reducing sugar?

Accepted Answer

Maltose

Question 8

What is the product when an aldose sugar is oxidized?

Accepted Answer

A carboxylic acid

Question 9

Which of the following statements about fatty acids is TRUE?

Accepted Answer

Cis double bonds in unsaturated fatty acids cause kinks in the hydrocarbon chain, lowering the melting point.

Question 10

Which of the following best describes the charge of a DNA molecule at physiological pH?

Accepted Answer

Negative due to the phosphate groups

Question 11

Which type of bond links nucleotides together in a single strand of DNA?

Accepted Answer

Phosphodiester bonds

Question 12

Given the DNA sequence 5'-ATGCGT-3', what is the complementary DNA strand?

Accepted Answer

3'-TACGCA-5'

Question 13

Which of the following is a difference between DNA and RNA?

Accepted Answer

RNA contains ribose, while DNA contains deoxyribose.

Question 14

Which of the following codons is a start codon in the genetic code?

Accepted Answer

$$\mathrm{AUG}$$

Question 15

How many hydrogen bonds form between guanine and cytosine in DNA?

Accepted Answer

$$3$$

Question 16

Which of the following best describes the effect of increasing temperature on enzyme activity?

Accepted Answer

Enzyme activity increases to an optimum temperature, then decreases due to denaturation.

Question 17

Which of the following is a function of the ribosome in protein synthesis?

Accepted Answer

It catalyzes the formation of peptide bonds between amino acids.

Question 18

Which of the following is a true statement about the hydrolysis of triacylglycerols?

Accepted Answer

Hydrolysis of triacylglycerols produces three fatty acids and one glycerol molecule.

Question 19

Which of the following best describes feedback inhibition in enzyme regulation?

Accepted Answer

The end product of a metabolic pathway inhibits an earlier enzyme in the pathway.

Question 20

Which of the following is a pyrimidine base found in nucleic acids?

Accepted Answer

Cytosine

CHEM 1301 Exam 4 Study Guide: Biomolecules and Biological Chemistry

Guida di studio - Domande di pratica

Study guide - Flashcard