BIOM9420
Clinical Laboratory Science
Sample Final Exam Questions
Final Exam 2011
Course
Code
BIOM9420
Course Title
Clinical
Laboratory
Science
Day
Fri
Date
28/10/2011
Start
Time
9.00am –
12.00 pm
Location
BioMed
Theatre
C
Candidate
Materials
Calculator UNSW
Approved
Exam Format
SECTION A
20 questions, 1 mark each
SECTION B
8 questions,
5 marks each
SECTION C
4 questions,
10 marks each
Example Questions
The following questions are multiple choice, 1 mark each. Circle the most correct
answer.
1.
2.
The resting cardiac output for Mr Bean is 5 L/min with a resting heart rate of 70
beats per minute. During exercise Mr Bean’s stroke volume would be:
(a)
70 ml/min
(b)
the same as his stroke volume at rest
(c)
increased proportional to exercise intensity
(d)
decreased proportional to exercise intensity
(e)
a maximum of 130 ml/min
In the investigation of possible kidney disease, a blood sample is often taken for
determination of various solutes in serum. Which of the following is probably not
of interest to the nephrologist?
(a)
Potassium
(b)
Bicarbonate
(c)
LDL-cholesterol
(d)
Creatinine
(e)
Urea
3.
4.
5.
6.
The technique of nuclear magnetic resonance can be applied to:
(a)
any radioactive nucleus
(b)
nuclei with an odd atomic number or odd atomic weight
(c)
nuclei with an odd atomic number that are NOT radioactive
(d)
1H, 13C, 32P and 23Na
(e)
only to water
Aerobic respiration occurs in:
(a)
mitochondria
(b)
cytoplasm
(c)
glycolysis
(d)
krebs cycle
(e)
yeast
White blood cells:
(a)
are the most abundant cell type found in blood
(b)
cannot be sorted by flow cytometry as their cell sizes are similar
(c)
are derived from megakaryocytes
(d)
are a major source of antibodies and host defence
(e)
are involved in the clotting cascade
The general equation for the initial velocity of a two-substrate enzyme reaction is
‫ ݒ‬ൌ ܸ௠௔௫ ቀ
ሾௌಲ ሿ
௄೘ಲ ାሾௌಲ ሿ
ቁቀ
ሾௌಳ ሿ
ቁ. The terms controlled by the enzyme alone are:
௄೘ಳ ାሾௌಳ ሿ
(a)
v, KmA, KmB
(b)
SA
(c)
KmA, KmB, Vmax
(d)
SB
(e)
Vmax
7.
White blood cells:
(a)
Are important because they make factors that control clotting
(b)
Are referred to as “white” because they form a white layer on the
sedimented red cells after centrifugation
(c)
Are not as important as red blood cells
(d)
Are difficult to sort out because their cell volumes are similar
(e)
Are the major source of antibodies and haemoglobin
The following questions are TRUE/FALSE statements, 1 mark each. Circle either TRUE
or FALSE after each statement.
8.
An enzyme assay has a reproducibility of 0.045 mg/ml and
an accuracy of 0.3 mg/ml. This may be because the
materials used to make the standard curve are pure, but the
sample is not.
TRUE
FALSE
TRUE
FALSE
Mean arterial pressure is the average over a cardiac cycle
and is determined by the cardiac output, systemic vascular
resistance and central venous pressure.
TRUE
FALSE
11.
Blood transports waste from the kidneys.
TRUE
FALSE
12.
Antibodies are useful in diagnostics because they are
specific and never give false positives
TRUE
FALSE
13.
The chemical equilibrium between ATP and ADP favours
the formation of ADP however cells maintain ATP at 1000
TRUE
fold higher concentration than ADP so that they are capable
of doing work.
FALSE
9.
A good diagnostic marker is highly specific for a certain
disease.
10.
Sample 5 mark questions
14.
The concentration of oxygen (molecular weight 32 Da) in water at 37oC and
100 mmHg is 0.14 mM. What volume of red blood cells, expressed as the
haematocrit (as a percent), is required to carry as much oxygen as water?
Assume :
• haemoglobin concentration in a red blood cell is 330 g/L
• molecular weight of haemoglobin is 64,500 Da
• each haemoglobin molecule binds 4 oxygen molecules.
H = haematocrit
Hb = haemoglobin
g
330
molHb
L  5.1 mmol

g
RBC
L
64500
mol
molHb 4molO2
[O2 ]  H 

RBC
molHb
20.5mmolO2
[O2 ]  H 
L
[O2 ]
0.14mM
H

 0.68%
mmolO2 20.5mM
20.5
L
15.







What are five functions of plasma?
Intravascular osmotic effect that maintains fluid and electrolyte balance.
Transport of insoluble substances by allowing them to bind to protein
molecules
Protein reserve for the body
Clotting
Inflammatory response and protection from infection – antibodies
Participation in the maintenance of the acid-base balance
Regulation of cell function and maintenance of homeostasis (inorganic
ions). Loss of potassium causes death.
Sample 10 mark question
16.
George, a 70kg adult, has 6L of blood circulating in his body. The heart pumps
blood at approximately 5L/min and the normal haemoglobin (MW 65000 Da)
count in males is 16 g per deciliter of blood.
(a)
How much oxygen is carried by blood per day per kg of body tissue?
[5 marks]
(b)
If one oxygen is required per NADH and six NADH are produced per
glucose metabolised, how much glucose, in grams, is metabolised per
day per kg of body tissue? [2 marks]
(c)
How many 60g mars bars, assuming all glucose, must George eat each
day to sustain this blood flow? [2 marks]
(d)
What does this imply about the body’s oxygen consumption? [1 mark]
(a)
Flow rate of haemoglobin = 5000 mL/min × 16 g/100mL × 1440 min/day
= 1152 kg/day
= 1152 kg/day ÷ 65000 g/mol = 17.72 mol/day
Oxygen flow rate = 4 × 17.72 mol/day ÷ 70 kg = 1mol/day/kg
(b)
Glucose consumption rate 1 mol/day/kg ÷ 6 = 0.17mol/day/kg = 30 g/day/kg
(c)
Mars bars = 30 g/day/kg ÷ 60 g/mars bar × 70 kg = 35 mars bars/day
(d)
Not all oxygen supplied is used in each cardiac cycle.