Deck 8: Protein Structure

Question 1

Post-translational modifications of proteins includes

A) Elongation
B) Replication
C) Transcription
D) Proteolytic cleavage
E) Initiation

Answer 1

D

Question 2

The linea r seq uen ce o f am ino ac ids tha t m ak e up a sing le polype ptide c hain is called its

A) Prim ary stru cture
B) Secon dary structure
C) Tertiary structure
D) Qua rternary structure
E) Code

Answer 2

A

Question 3

An ex am ple of a po lar am ino ac id is

A) Tryptophan
B) Arginine
C) As pa rtic ac id
D) Serine
E) Phenylalanine

Answer 3

D

Question 4

The final three-dimensional structure of proteins is important because

A) The pictures are awesome
B) Protein function occurs through interactions on the surfaces of the proteins
C) They are not two-dimensional structures
D) Am ino acids nearby in the 3D structure are us ually not adjacent in the primary structure
E) The structure is dictated by the function

Question 5

"Hydrophobicity" of an amino acid describes

A) The num ber of hydrocarbons in its R group
B) Its ability to dissolve in water
C) Its preference for non-polar solvents over water
D) T he nu m be r of po lar gro up s o n th e a m ino ac id
E) T he nu m be r of ch ar ge d g ro up s o n th e a m ino ac id

Question 6

Chemical post-translational modifications include all of the following EXCEPT

A) Phosphorylation
B) Methylation
C) Ubiquitinylation
D) Acetylation
E) Transesterification

Question 7

N-link ed g lycosylation occ urs whe n ca rboh ydrate grou ps a re ad ded to

A) The side chain NH₂ of asparagine
B) The side chain NH₂ of lysine
C) The side chain N of histidine
D) The side chain N of N-acetylglucosamine
E) The side chain NH₂ of serine

Question 8

All a m ino ac ids co nta in

A) An amino group (-NH 2)
B) An asymm etric carbon
C) A carboxyl group (-COOH)
D) A, B and C
E) A and C

Question 9

Peptide bonds form on the ribosome between

A) T he am ino gro up of a lysin e R ch ain an d th e c ar bo xyl g ro up of a n a sp ar tic R ch ain
B) The carb oxyl group on the carboxyl terminus of the growing chain and the amino gro up of th e ne xt am ino acid
C) The amino group on the amino terminus of the growing chain and the carboxyl group of the ne xt a m ino ac id
D) Am ino and carboxyl groups of adjacent amino acids in the interior of the polypeptide
E) The alpha carbon and the R group

Question 10

Non-polar amino acids include all of the following EXCEPT

A) Tryptophan
B) Phenylalanine
C) Leucine
D) Lysine
E) Valine

Question 11

Which of the following is NOT one of the non-covalent interactions that stabilize protein structure?

A) Hydrogen bonding
B) Electrostatic attraction/repulsion
C) Hydrophobic interactions
D) Quantum tunneling
E) Steric hindrance

Question 12

Proteins can be anchored to mem branes by

A) Co va lent atta ch m en t of th e pr ote in to GP I (glyc os yl ph os ph atid yl ino sito l)
B) Covalent attachment to retinal in membranes
C) Linkage to myristic acid through the carboxyl terminal COOH
D) Linkage to myristic acid through cysteine
E) Linkage to farnesyl through the N-terminus

Question 13

O- linke d glyco sylation o ccu rs w hen carb ohyd rate g roup s are add ed to

A) The hydroxyl group of threonine
B) The hydroxyl group of hydroxyproline
C) The hydroxyl group of serine
D) The hydroxyl group of tyrosine
E) Both A and C are correct

Question 14

Which of the following amino acids is most hydrophobic?

A) Lysine
B) As pa rtic ac id
C) Serine
D) Tyrosine
E) Isoleucine

Question 15

Arginine is an exam ple of a

A) Ac idic am ino ac id
B) Ba sic a m ino acid
C) N on -p ola r am ino ac id
D) Po lar am ino ac id
E) Ar om atic am ino ac id

Question 16

Phosphorylation of proteins typically occurs at which of the following amino acids?

A) As pa rtic ac id
B) Serine
C) Tryptophan
D) Phenylalanine
E) Proline

Question 17

An ex am ple of a no n- po lar am ino ac id is

A) Tyrosine
B) Histidine
C) Threonine
D) G luta m ic a cid
E) Leucine