Question 1

Which intermolecular force is primarily responsible for the high boiling point of water compared to methane?

Accepted Answer

Hydrogen bonding

Question 2

A student is titrating a weak acid with a strong base. Which equation should they use to calculate the pH at any point before the equivalence point?

Accepted Answer

Henderson-Hasselbalch equation: $$pH = pK_a + \frac{[A^-]}{[HA]}$$

Question 3

Which of the following best explains why oil droplets float on water?

Accepted Answer

Oil is less dense than water and hydrophobic interactions prevent mixing

Question 4

Which statement about the Gibbs free energy ($$\Delta G) of a $$reaction is correct?

Accepted Answer

A negative $$\Delta G$$ means the reaction is spontaneous

Question 5

During glycolysis, ATP hydrolysis is coupled to other reactions. What is the main reason for this coupling?

Accepted Answer

To drive endergonic reactions by providing free energy

Question 6

Which carbohydrate is a major storage form of energy in animals?

Accepted Answer

Glycogen

Question 7

Which type of lipid is most likely to be found in membrane rafts and is important for cell signaling?

Accepted Answer

Cholesterol

Question 8

The Michaelis-Menten equation describes enzyme kinetics. What does $$K_m$$ represent?

Accepted Answer

The substrate concentration at which the reaction rate is half of $$V_{max}$$

Question 9

Which of the following amino acids is most likely to form a disulfide bond in a protein?

Accepted Answer

Cysteine

Question 10

Which nucleic acid base pairing is correct for DNA?

Accepted Answer

Adenine pairs with thymine

Question 11

Which process occurs in the nucleus of eukaryotic cells but not in prokaryotic cells?

Accepted Answer

mRNA splicing

Question 12

A mutation changes a codon from UAU (tyrosine) to UAC (tyrosine). What type of mutation is this?

Accepted Answer

Silent mutation

Question 13

Which of the following is a function of the spliceosome?

Accepted Answer

Removing introns from pre-mRNA

Question 14

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

Accepted Answer

Enzyme activity increases up to an optimal temperature, then decreases due to denaturation

Question 15

Which of the following is a pyrimidine base found in DNA?

Accepted Answer

Thymine

Question 16

What is the main consequence of a frameshift mutation in a coding region of DNA?

Accepted Answer

It alters the reading frame, potentially changing all downstream amino acids

Question 17

Which of the following is true about the quaternary structure of proteins?

Accepted Answer

It involves the arrangement of multiple polypeptide chains

Question 18

Which process is responsible for the addition of a 5' cap to eukaryotic mRNA?

Accepted Answer

Capping enzyme activity

Question 19

Which of the following best describes competitive inhibition of an enzyme?

Accepted Answer

The inhibitor binds to the active site, increasing $$K_m$$ but not affecting $$V_{max}$$

Question 20

Which of the following is a real-world example of a genetic disease caused by a single nucleotide mutation?

Accepted Answer

Sickle cell anemia

Pharmaceutical Biochemistry PC 1112: Comprehensive Study Notes

Guida di studio - Domande di pratica