Post on 03-Jan-2016
Question 1
Approximately what mass percent of a body’s dry weight consists of proteins?
a) 5%
b) 25%
c) 50%
d) 72%
Answer: C) sorry, did I forget to mention that in
class?
Question 2
Which functional group, in addition to an amine, do all amino acids contain?
a) an alcohol
b) an amide
c) a carboxylic acid
d) an oxyacid
Answer: C)
Question 3
A peptide bond links
a) an alcohol and a ketone
b) an amide and an aldehyde
c) an amine and a carboxylic acid
d) an amide and a carboxylic acid
Answer: C) H2N CH C
CH3
O
HN CH C
CH2
OH
O
SH
peptide bondamine carboxylic acid
Question 4
What does the term ‘α-amino acid mean?
a) The amino acid attaches to the carbon in the carboxyl group
b) The amino group attaches to the carbon next to the carboxylic acid group
c) The amino acid contains only one carbon atom
d) The amino acid contains only one carboxylic acid group
Answer: b)
H2N CH C
CH
OH
O
OH
CH3
-carbon atom
Question 5
When referring to amino acids, what does the term essential mean? These are acids which
a) are necessary for digestion
b) are necessary for respiration
c) are synthesized in our bodies
d) we must obtain from our diet
Answer: d)
Question 6
Which of the following amino acids is not basic?
a) arginine
b) glycine
c) histidine
d) lysine
Answer: b)
Question 7
Which of the following amino acids is acidic?
a) alanine
b) aspartic
c) glycine
d) valine
Answer: b)
H2N CH C
CH2
OH
O
C
OH
O
Question 8
Which one of the following amino acids contains a double ring structure?
a) phenylalanine
b) proline
c) tryptophan
d) tyrosine
Answer: C)
H2N CH C
CH2
OH
O
HN
Question 9
Which one of the following amino acids contains a benzyl group?
a) glycine
b) isoleucine
c) methionine
d) phenylalanine
Answer: d)
H2N CH C
CH2
OH
O
Question 10
What does the term hydrophobic mean?
a) water reactive
b) water repelling
c) water soluble
d) water proof
Answer: b)
Question 11
Which of the following amino acids is hydrophobic?
a) leucine
b) serine
c) threonine
d) tyrosine
Answer: a)
H2N CH C
CH2
OH
O
CH CH3
CH3
non-polar side chain
Question 12
All but one of the common amino acids contain a –NH2 amino group. Which one contains an –NH- amino acid as part of a ring structure?
a) phenylalanine
b) proline
c) tryptophan
d) tyrosine
Answer: b) HN
C OH
O
Question 13
In how many different ways can the amino acids: ALA, CYS, MET, GLU, SER and TYR connect together to form a polypeptide?
a) Over 5000
b) 720
c) 120
d) 21
Answer: b) 6! = 720
Question 14
The diagram is an example of:
a) An L-amino acid
b) A D-amino acid
c) An achiral-amino acid
d) An amino acid residue
Answer: a)
C
C
R
HH2N
O OH
Question 15
What kind of bonding stabilises helical and β-pleated-sheet secondary protein structure?
a) Vander Waals forces
b) Hydrogen bonding
c) Interactions with neighbouring protein chains
d) Helical and sheet structures are tertiary, not secondary structures
Answer: b)