Question 1

Which of the following best explains the primary driving force for protein folding in aqueous environments?

Accepted Answer

Hydrophobic effect, which buries nonpolar residues in the protein core

Question 2

A protein contains both alpha helices and beta sheets. According to the rules of protein folding, how are these secondary structures most likely arranged?

Accepted Answer

They are usually found in separate layers due to lack of hydrogen bonding between them

Question 3

Which of the following amino acids is most likely to be abundant in intrinsically disordered proteins (IDPs)?

Accepted Answer

Lysine

Question 4

Which statement about the folding of proteins is correct?

Accepted Answer

Protein folding is a highly cooperative process

Question 5

Given the equation for the fraction of protein bound to ligand $$Y = \frac{[L]}{K_d + [L]}$$, what is the value of $$Y$$ when $$[L] = K_d$$?

Accepted Answer

$$Y = 0.5$$

Question 6

Which of the following best describes the quaternary structure of hemoglobin?

Accepted Answer

A tetramer composed of two alpha and two beta subunits, each with a heme group

Question 7

Which of the following factors does NOT typically cause protein denaturation?

Accepted Answer

Mild agitation

Question 8

A Hill coefficient ($$n) $$greater than 1 in the equation $$Y = \frac{[L]^n}{K_d + [L]^n}$$ indicates:

Accepted Answer

Positive cooperativity

Question 9

Which immunoglobulin is most abundant in blood plasma and is responsible for secondary immune response?

Accepted Answer

IgG

Question 10

Which of the following best describes the function of the variable domains in an antibody?

Accepted Answer

They recognize and bind specific antigenic determinants (epitopes)

Question 11

Which of the following statements about the denaturation of ribonuclease A is supported by experimental evidence?

Accepted Answer

Removal of denaturant and reducing agent allows the protein to refold and regain activity

Question 12

Which of the following best describes the role of heme in myoglobin and hemoglobin?

Accepted Answer

It binds and releases oxygen reversibly

Question 13

Which of the following is a correct statement about the immune response to small molecules (less than 5000 Da)?

Accepted Answer

Small molecules must be conjugated to a larger carrier to elicit an immune response

Question 14

Which of the following best describes the structure of secreted IgM?

Accepted Answer

Pentamer with ten antigen-binding sites

Question 15

Which of the following is a function of intrinsically disordered proteins (IDPs)?

Accepted Answer

They can act as spacers, linkers, or scavengers for ions or small molecules

Question 16

Which of the following best describes the difference between myoglobin and hemoglobin?

Accepted Answer

Myoglobin is a monomer, hemoglobin is a tetramer

Question 17

Which of the following is true regarding the Hill plot for ligand binding?

Accepted Answer

A slope equal to the number of binding sites indicates perfect cooperativity

Question 18

Which of the following best describes the role of the Fc region of IgG in immune response?

Accepted Answer

It binds to Fc receptors on macrophages, triggering phagocytosis

Question 19

Which of the following statements about the folding funnel model of protein folding is correct?

Accepted Answer

The native state is at the bottom of the funnel, representing the lowest free energy

Question 20

Which of the following best describes the function of myosin in muscle contraction?

Accepted Answer

It hydrolyzes ATP to generate force for movement along actin filaments

Protein Structure, Folding, and Function: Advanced Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard