LFS251Biochemistry 2023: Task 1a, Problem Set
LFS251Biochemistry 2023: Task 1a, Problem Set
The Problem Set will require you to use knowledge gained from the learning materials (especially Modules 1-3), and to undertake self-directed reading in biochemistry literature (particularly Garrett & Grisham, but other texts also as required). This assessment item is worth 15% of your overall grade. Submit via Canvas by 4.00 pm on Thursday, 23rd March (Week 4). Penalties for late submissions apply, as per University procedures. References are not required. There are 8 questions; marks as indicated.
Question 1[1 Mark]
Glutamic acid is an amino acid (See Garrett and Grisham, 6th Edition, Figure 4.3 for the structure). The pKa values for the carboxyl group, amino group and side chain are reported in Garrett and Grisham, 6th Edition, Table 4.1. Based on your knowledge of the general structure of amino acids, and the ionization of amino acids with changing pH, draw a diagram of the major species of glutamic acid as it would appear in the blood circulation.
[If you dont have the 6th Edition, this text can be viewed at the library]
(1 Mark)
Question 2[2 Marks]
Which TWO of the following molecules would be described as amphipathic?
(Both molecules must be correct for the mark)
_________ and ___________
(2 Marks)
Question 3[3 Marks]
Tris buffer (pKa=8.3) is made to a concentration of 0.4 M. Determine the concentration of the conjugate base at pH 4.9. (Show your working and include units for full marks)
Q3 answer:
Concentration of the conjugate base =
(3 Marks)
Question 4[1 Mark]
The diagram illustrates RNA polymerase that is reading the template strand of DNA to give rise to the RNA transcript. A short sequence of nucleotides (bases shown only) has been included for the template and non-template strands of DNA. On the dashed line, include the corresponding sequence of bases for the RNA transcript.
466725-504825C
A
T
T
T
C
A
A
G
G
00C
A
T
T
T
C
A
A
G
G
Q4 Answer: __ __ __ __ __
(1 Mark)
Question 5[1 Mark]
Which of the following terms correctly describes the globular protein, haemoglobin?
Monomeric protein
Homomultimeric protein
Heteromultimeric protein
Homodimer
Q5 Answer: (1 Mark)
Question 6[3 Marks]
a) How many chiral centres are there in the molecules below?
Molecule 1: (1 Mark)
Molecule 2: (1 Mark)
b) Which of the following pairs of molecules are diastereomers, but not epimers?
Pair (a)
Pair (b)
Pair (c)
Q6b Answer: (1 Mark)
Question 7[3 Marks]
What is the term that matches the following descriptions?
The catalytically active complex of protein (apoenzyme) and prosthetic group (coenzyme)
Q7a Answer: (1 Mark)
Form of enzyme kinetics where a constant proportion of reactant is metabolised per unit time. This form of kinetics is a concentration-dependent process.
Q7b Answer: (1 Mark)
RNA molecule that has catalytic activity.
Q7c Answer: (1 Mark)
Question 8[1 Mark]
Provide the IUPAC (International Union of Pure and Applied Chemistry) name for the fatty acid below.
Q8 Answer: (1 Mark)
