SAMPLE STRUCTURE

Final written examination in

MEDICAL BIOPHYSICS, BIOMETRICS AND COMPUTER TECHNOLOGY

First name:................................ Surname:..................................... Date:...............................

Time limit: 60 minutes

Grade Scale: The maximum score is 30 points,

A…30-28, B…27.5-25.5, C…25-23, D…22.5-20.5, E…20-18, F…less than 18

Part 1

In the following 11 multiple choice questions, there is always ONE correct answer. Each of these

correct answers is evaluated by one point. Indicate your choice by writing a letter (A), (B), etc.

1. The value of the normal atmospheric pressure is approximately

A) 1 Torr B) 100 Torr C) 760 Pa D) 100 kPa E) 760 kPa

2. The most important ion in the establishment of the membrane potential during the

depolarization of a neuron cell is

A) Na+ B) K+ C) Ca+2 D) Cl- E) HCO3-

3. According to the Frank-Starling law, the strength of ventricular contraction is

A) directly proportional to the end-diastolic volume

B) inversely proportional to the end-diastolic volume

C) independent on the end-diastolic volume

4. The tidal volume in a normal man at rest is about

A) 0.5 L B) 1.2 L C) 2.5 L D) 4.5 L E) 6.0 L

5. Which of the following parts of the eye has the greatest concentration of rods?

A) ciliary body B) iris C) optic disk D) fovea E) parafoveal region

6. Which of the labels identifies the part of the ECG that corresponds to atrial depolarization?

A) A B) B C) B+C+D D) E+F E) F

7. If the person with normal lung function were to hyperventilate for several seconds, there would

be a significant

A) increase in the arterial pO2

B) decrease in the arterial pCO2

C) increase in the arterial percent oxyhemoglobin saturation

D) decrease in the arterial pH

8. Select the right statement

A) The tissue absorption of ultrasound increases with increasing frequency.

B) The absorption of ultrasound in blood is greater than in muscle.

C) The typical range of ultrasound frequencies used in medicine is usually 1-10 Hz.

D) The velocity of ultrasound does not depend on the density of the medium.

9. Select the right statement

A) A peak at 0.51 MeV in an energy spectrum may be the result of an interaction between γ photon and

α particle released from the photocathode.

B) α particle is consisted of two protons and two electrons.

C) The approximate gamma detection efficiency of a GM tube counter is 10 percent.

D) γ-rays have a higher energy than x-rays.

10. When the radius of the resistance vessels is increased, which of the following is increased?

A) systolic blood pressure

B) diastolic blood pressure

C) viscosity of the blood

D) hematocrit

E) capillary blood flow

11. Determine the elements X and Y in the following nuclear reaction (transmutation)

7N14

+ X ���� 9Fe18

���� Y + 1H1

A) X = 3Li3, Y = 8O

17

B) X = 2He4, Y = 8O

18

C) X = 2He4, Y = 8O

17

D) X = 2He4, Y = 8O

16

E) X = 4Be2, Y = 8O

18

Part 2

In the following questions, there are 5 physical problems. Each of these correct answers is

evaluated by three points; 1 point for a correct FINAL formula, the 2nd point for correct

calculation and 3rd point for correct unit.

1. A patient has a heart rate of 67 beats/min, a pulmonary vein O2 content of 0.21 ml O2 /ml blood, a

stroke volume of 77 ml/beat, and a pulmonary artery O2 content of 0.14 ml O2 /ml blood. What is this

patient’s oxygen consumption?

2. Four veins with radius r1 and flow speed Q1 combine to form one vein with radius r2 = 4 x r1. Find

the flow speed in the larger vein.

3. If the velocity of sound in tissue is 1 500 m.s-1 what is the wavelength of 10 MHz ultrasound?

4. Determine the heart rate and direction of the electrical heart axis from the given ECG record.

Compare these values with the normal physiological heart function.

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5. A randomized controlled trial is designed to evaluate the efficacy of a new drug in lowering cholesterol. 30

participants are enrolled in the trial and are randomly assigned to receive either the new drug or a placebo. The

participants do not know which treatment they are assigned. Each participant is asked to take the assigned

treatment for 6 weeks. At the end of 6 weeks, each patient’s total cholesterol level is measured and the sample

statistics are shown in Table below. Is there statistical evidence of a reduction in mean total cholesterol in patients

taking the new drug for 6 weeks as compared to participants taking a placebo?

Sample size Mean Standard deviation

New drug 15 195.9 28.7

Placebo 15 217.4 30.3

Choose the appropriate test statistics and critical value:

The 0.05 critical value from the appropriate distribution with 15 degrees of freedom is - 2.131.

The 0.05 critical value from the appropriate distribution with 28 degrees of freedom is - 2.048.

The 0.05 critical value from the appropriate distribution with 29 degrees of freedom is - 2.043.

The 0.05 critical value from the appropriate distribution with 30 degrees of freedom is - 2.042.

Part 3

In the following 2 questions, you should write the direct answer. The correct answers will be

maximally evaluated by two points.

1. List the factors affecting cardiac output and the effect of each.

2. Describe the main biophysical functions of the middle ear.

Total points:..............

Final examination grade:..............

...............………………………..…

Examiner’s signature

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