Structural Biochemistry 1 (BCHS3101)
BSc, Chemistry - CHMS
Semester: Resit
Level: 300
Year: 2018
REPUBLIC OF CAMEROON THE UNIVERSITY OF BAMENDA
Peace-Work-Fatherland
P. O. BOX 39 Bambili
School/Faculty:FS Department:_Biochemistry Lecturer(s): Pr Mbouobda & Dr Nantia ____
Course Code: _BCHS3101_______ Course Title: Structural Biochemistry I__
Date: _06/09/2018_______Hall: __Asanji ________Time: 15:00-17:00__
Answer all Questions.
Exercise 1 (14 marks) MCQ
1. All proteins contain the: (A) Same 20 amino acids; (B) Different amino acids; (C) 300 Amino acids
occurring in nature; (D) Only a few amino acids; (E) A and D
2. Proteins contain: (A) Only L- a - amino acids (B) Only D-amino acids (C) DL- Amino acids (D) Both (A) and
(B) (E) none
3. The optically inactive amino acid is: (A) Glycine (B) Serine (C) Threonine (D) Valine
4. pH (isoelectric pH) of alanine is: (A) 6.02 (B) 6.6 (C) 6.8 (D) 7.2
5. Amino acid with side chain containing basic groups is: (A) 2-Amino 5-guanidovaleric acid (B) 2-Pyrrolidine
carboxylic acid (C) 2-Amino 3-mercaptopropanoic acid (D) 2- Amino propanoic acid (E) none
6. An amino acid that does not form an u-helix is: (a) V (b) P (c) Y (d) W (c) none
7. Which of the following is non polar unchagerd non essential amino acids? a- A & G b- L &P c-L&G d-A&P
e-S&V.
8. Which of the following pairs of amino acids carry a negative charge on their side chain at pH 8?a-N & Q b-
L&G c-H&K d-D & E e-S & Y.
9. Which of the following of amino acids cannot form hydrogen bond with their side (R) group? a- Y b- C c- L.
d- S e- G
10. The globular proteins are characterized by all the following Except: a- the axial ratio is less than 10 b-
they include albumin & globulin c- they are less stable than fibrous proteins d- they include keratin & myosin e-
is the shape of tertiary structure of proteins.
11. Special arrangement of subunits of proteins that consists of more than one monomer is referred to as : a-
primary structure of protein b- secondary structure of protein c- tertiary structure of protein d- quaternary
structure of protein e) c and d
12. A tripeptide functioning as an important reducing agent in the tissues is: (A) Bradykinin (B) Kallidin (C)
Tyrocidin (D) Glutathione (E)None
13. A peptide which acts as potent smooth muscle hypotensive agent is: (A) Glutathione (B) Bradykinin (C)
Tryocidine (D) Gramicidin-s (E) Oxytocin
14. Each turn of a-helix contains the amino acid residues (number): (A) 3.6 (B) 3.0 (C) 4.2 (D) 4.5
(E)None
15. In a protein molecule the disulphide bond is not broken by: (A) Reduction (B) Oxidation (C) Denaturation
(D) X-ray diffraction (E) (A) & (C)
16. The a-helix of proteins is: (A) A pleated structure (B) Made periodic by disulphide bridges (C) A non-
periodic structure - (D) Stabilised by hydrogen bonds between NH and CO groups of the main chain
Exercise 4 (10 marks)
1) Give the structure and a biological function of cAMP, UTP (4 marks)
2) In a table differentiate between the primary and secondary structure of DNA (4 marks)
3)Match the type of bond with the role below: (2 marks)
Bond type Role
(a) Phosphodiester 1__Links base to pentose in nucleotide
(b) N-glycosidic 2__joins adjacent nucleotides in one strand
(c) Phosphate ester bonds 3__joins complementary nucleotides in two
(d) hydrogen 4__difference between a nucleoside and a nucleotide
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Exercise 2 (45 marks)
1) Mrs Diana endeavors to characterize the carbohydrate A named: β-D-glucopyranosyl -1-6- β -D-
glucopyranose.
a) Define and justify the specific class of A (2 mrks).
b) Give the pyranose representation of A (3 mrks)
2) Write the complete equation of each of the following reactions (4.5 mrks).
i- esterification of lauric acid and ethanol
ii- reaction of oleic acid with NaOH
iii- hydrogenation of arachidonic acid
3) Give the biological functions of lipids and carbohydrates (5 mrks).
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