1. Practice Quiz (you will need your amino acid sheet for this quiz)
Amino acids & peptides
Practice Quiz
(you will need your amino acid sheet for this quiz)

2. Question 1
Approximately what mass percent of a body’s dry weight consists of proteins? 5%
25%
50%
72%
Answer: C) sorry, did I forget to mention that in class?

3. Question 2
Which functional group, in addition to an amine, do all amino acids contain?
an alcohol
an amide
a carboxylic acid
an oxyacid
Answer: C)

4. Question 3 A peptide bond links an alcohol and a ketone
an amide and an aldehyde
an amine and a carboxylic acid
an amide and a carboxylic acid
Answer: C)

5. Question 4 What does the term ‘α-amino acid mean?
The amino acid attaches to the carbon in the carboxyl group
The amino group attaches to the carbon next to the carboxylic acid group
The amino acid contains only one carbon atom
The amino acid contains only one carboxylic acid group
Answer: b)

6. Question 5
When referring to amino acids, what does the term essential mean? These are acids which
are necessary for digestion
are necessary for respiration
are synthesized in our bodies
we must obtain from our diet
Answer: d)

7. Question 6 Which of the following amino acids is not basic? arginine
glycine
histidine
lysine
Answer: b)

8. Question 7 Which of the following amino acids is acidic? alanine
aspartic
glycine
valine
Answer: b)

9. Question 8
Which one of the following amino acids contains a double ring structure?
phenylalanine
proline
tryptophan
tyrosine
Answer: C)

10. Question 9
Which one of the following amino acids contains a benzyl group?
glycine
isoleucine
methionine
phenylalanine
Answer: d)

11. Question 10 What does the term hydrophobic mean? water reactive
water repelling
water soluble
water proof
Answer: b)

12. Question 11 Which of the following amino acids is hydrophobic? leucine
serine
threonine
tyrosine
Answer: a)

13. 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?
phenylalanine
proline
tryptophan
tyrosine
Answer: b)

14. Question 13
In how many different ways can the amino acids: ALA, CYS, MET, GLU, SER and TYR connect together to form a polypeptide?
Over 5000
720
120 21
Answer: b) 6! = 720

15. Question 14 The diagram is an example of: An L-amino acid
A D-amino acid
An achiral-amino acid
An amino acid residue
Answer: a)

16. Question 15
What kind of bonding stabilises helical and β-pleated-sheet secondary protein structure?
Vander Waals forces
Hydrogen bonding
Interactions with neighbouring protein chains
Helical and sheet structures are tertiary, not secondary structures
Answer: b)

17. Who’s your favourite Chemistry teacher?
A Kevin
A nother
A non
None of the above
Answer: a) A Kevin
(of course)