2018 Past Exam

Question 1

The phospholipids in the plasma membrane have
A) hydrophilic tails orientated towards the centre of the membrane
B) hydrophilic tails orientated towards the extracellular and intracellular fluids
C) hydrophobic heads orientated towards the extracellular and intracellular fluids
D) hydrophobic tails orientated towards the centre of the membrane
E) hydrophobic heads orientated towards the centre of the membrane

Answer 1

D (hydrophobic tails orientated towards the centre of the membrane)

Question 2

Primary active transport uses
A) channels to move molecules against the concentration gradient
B) ATP to move molecules against the concentration gradient
C) ATP to move molecules down the concentration gradient
D) ATP to facilitate the diffusion of molecules
E) membrane-bound vesicles to move molecules into the cell

Answer 2

B (ATP to move molecules against the concentration gradient)

Question 3

Type IIb skeletal muscle fibres may fatigue due to accumulation of 
A) Ca2+
B) lactic acid
C) ATP
D) phosphate
E) fatty acids

Answer 3

B

Question 4

Free nerve endings respond
A) and slowly adapt to painful stimuli
B) and slowly adapt to pressure stimuli
C) and slowly adapt to light touch
D) and rapidly adapt to painful stimuli
E) and rapidly adapt to light touch

Answer 4

A? (and slowly adapt to painful stimuli)

Question 5

G-protein coupled receptors
A) are embedded in the plasma membrane and signal through second messengers
B) are found within the cytoplasm and bind directly to DNA
C) are found within the cytoplasm and have kinase activity
D) are embedded in the plasma membrane and bind directly to DNA
E) are found within the cytoplasm and signal through second messengers

Answer 5

A (are embedded in the plasma membrane and signal through second messengers)

Question 6

Which of the following statements about the heart sounds is CORRECT?
A) The second heart sound occurs when the atrioventricular (AV) valves close
B) The first heart sound occurs when the pressure in the ventricle is less than the atria
C) The second heart sound occurs during ventricular systole
D) The second heart sound occurs when the pressure in the ventricle is lower than the aorta
E) The first heart sound occurs when the atrioventricular (AV) valves open

Answer 6

D (The second heart sound occurs when the pressure in the ventricle is lower than the aorta)

Question 7

You have measured a patient’s blood pressure using a sphygmomanometer, and you have determined that their blood pressure is 130/90. Which of the following statements about this procedure is CORRECT?
A) A sound is heard when diastolic pressure is higher than the cuff pressure
B) The absence of sound indicates turbulent blood flow
C) Blood flow through the brachial artery was turbulent at 130 mm Hg
D) A sound was heard above 130 mm Hg and below 90 mm Hg
E) The first sound heard as the cuff pressure decreases is the diastolic pressure

Answer 7

A (google docs)

Question 8

The Frank-Starling law of the heart states that
A) increasing venous return will increase end systolic volume
B) increasing end diastolic volume will increase end systolic volume
C) decreasing venous return will increase cardiac output
D) decreasing venous return will increase stroke volume
E) increasing end diastolic volume will increase stroke volume

Answer 8

E (increasing end diastolic volume will increase stroke volume)

Question 9

During exercise, O2 is consumed by cells and CO2 is produced. A decrease in O2 in exercising skeletal muscle will cause
A) metarterioles to open, resulting in an increase in blood flow to the tissues
B) arterioles to dilate, resulting in an increase in blood flow to the tissues
C) precapillary sphincters to open, resulting in an increase in total peripheral resistance
D) arterioles to dilate, resulting in an increase in mean arterial blood pressure
E) arterioles to constrict, resulting in a decrease in capillary blood flow

Answer 9

B (arterioles to dilate, resulting in an increase in blood flow to the tissues)

Question 10

The sympathetic nervous system plays an important role in regulating blood pressure. Which of the following cardiovascular changes is associated with the sympathetic nervous system?
A) decreased cardiac output, resulting in decreased blood pressure
B) venous constriction, resulting in increased end systolic volume
C) arteriolar constriction, resulting in increased cardiac output
D) decreased heart rate, resulting in decreased cardiac output
E) increased strength of ventricular contraction, resulting in increased stroke volume

Answer 10

E? (google docs)

Question 11

An important role for Type 1 alveolar cells is to
A) form the thin respiratory membrane for gas diffusion
B) make and secrete mucus
C) increase the surface area of the lungs
D) produce surfactant
E) sweep particulates to the pharynx for swallowing

Answer 11

A? (form the thin respiratory membrane for gas diffusion)

Question 12

For a normal healthy subject at rest
A) inspiration requires no muscular activity because of the recoil of the chest
B) expiration requires active contraction of the diaphragm
C) inspiration is active, relying mainly on contraction of the diaphragm
D) inspiration is active, relying mainly on contraction of the abdominal muscles
E) expiration requires contraction of abdominal muscles

Answer 12

C (inspiration is active, relying mainly on contraction of the diaphragm)

Question 13

A reduction in pulmonary surfactant leads to
A) a decrease in elastic recoil
B) an increase in intrapleural pressure
C) an increase in alveolar surface tension
D) an increase in lung compliance
E) an increase in airway resistance

Answer 13

C (an increase in alveolar surface tension)

Question 14

Haemoglobin saturation with O2 decreases as 
A) temperature decreases
B) PCO2 increases
C) H+ decreases
D) HCO3- decreases
E) PO2 increases

Answer 14

B? (google docs)

Question 15

To control ventilation, the central chemoreceptors monitor levels of 
A) O2 in the brain extracellular fluid
B) CO2 in the brain extracellular fluid
C) O2 in the arterial blood
D) H+ in the brain extracellular fluid
E) CO2 in the arterial blood

Answer 15

D? (H+ in the brain extracellular fluid)

Question 16

(see exam for graph)
From the following figure regarding pain relief, which statement is CORRECT?
A) Drug D is more potent than aspirin
B) Aspirin and Drug D are equally efficacious
C) Morphine is less potent and less efficacious than Drug D
D) Codeine is less potent than morphine
E) Codeine is 10-fold more potent than DrugD

Answer 16

D? (google docs)

Question 17

When discussing potency, efficacy and antagonism, which of the following statements is CORRECT?
A) Agonists and antagonists have both potency and efficacy
B) If a drug is potent, it must be very efficacious
C) Pharmacological antagonists bind to receptors and produce a cellular response opposing that of the agonist
D) All drugs binding to one receptor type have differing potencies and similar efficacies
E) Physiological antagonists bind to receptors and produce a cellular response, which opposes that of the agonist

Answer 17

E

Question 18

In the presence of a competitive antagonist, the agonist concentration-response curve is
A) not shifted right or left but shows a decreased maximum effect
B) shifted to the left without a change in slope or maximum effect
C) shifted to the left with a decreased slope and maximum effect
D) shifted to the right without a change in slope or maximum effect
E) shifted to the right with a decreased slope and maximum effect

Answer 18

D (shifted to the right without a change in slope or maximum effect)

Question 19

Drug metabolism
A) always results in the formation of metabolites that have less biological activity than the drug itself
B) facilitates the excretion of drugs in urine as water-soluble metabolites
C) occurs whether the drug is absorbed by the body or not
D) occurs primarily in the kidney
E) always occurs sequentially as Phase I and Phase II reactions

Answer 19

B?

Question 20

Which of the following statements about angina and its treatment is INCORRECT?
A) Organic nitrates may be used to promote relaxation of the heart muscle
B) Angina occurs when the heart muscle is not sufficiently oxygenated to carry out its functions
C) Vasodilators can assist with improving coronary blood flow
D) Angina is classified as either stable or unstable, depending on the blockage and discomfort experienced
E) β-Adrenoceptor agonists can improve cardiac output by binding to the β1-adrenoceptors and increasing cardiac function

Answer 20

E

Question 21

Which one of the following drugs is used to treat the symptoms of heart failure by increasing the strength of heart contractions?
A) digoxin
B) β-adrenoceptor antagonists
C) angiotensin-converting enzyme (ACE) inhibitors
D) diuretics
E) vasodilators

Answer 21

A (digoxin)

Question 22

Which pairing of asthma phase and effective treatment is CORRECT?
A) early phase: β2-adrenoceptor antagonists; late phase: glucocorticoids
B) early phase: long-acting β2-adrenoceptor agonists; late phase: immunoglobulin E (IgE) antibody treatment
C) early phase: short-acting β2-adrenoceptor agonists; late phase: leukotriene receptor agonists
D) early phase: leukotriene receptor antagonists; late phase: short-acting β2-adrenoceptor agonists
E) early phase: short-acting β2-adrenoceptor agonists; late phase: glucocorticoids

Answer 22

E? (early phase: short-acting β2-adrenoceptor agonists; late phase: glucocorticoids)

Question 23

Glucocorticoids can be either inhaled or taken orally for the treatment of asthma inflammation. Single large doses given orally are usually not a problem, but long term use can result in a number of adverse effects. Which of the following is NOT a possible adverse effect of glucocorticoids used long term?
A) increased risk of osteoporosis
B) Cushing’s syndrome
C) enhanced immune response with chronic use
D) increased risk of cataracts
E) inhibition of tissue growth, especially in children

Answer 23

C (enhanced immune response with chronic use)

Question 24

List and explain the THREE (3) different types of endocytosis.

Answer 24

• receptor mediated endocytosis: uptake triggered when target molecule binds to receptors on the plasma membrane
• pinocytosis: cell drinking = uptake of ECF
• phagocytosis: cell eating = uptake of solid objects such as bacteria and cellular debris

Question 25

Mean arterial blood pressure is affected by cardiac output and total peripheral resistance. Define BOTH cardiac output and total peripheral resistance. Explain the main mechanisms that can INCREASE CARDIAC OUTPUT.

Answer 25

Cardiac output is the volume of blood pumped by each ventricle/min. The total peripheral resistance is the amount of resistance in the circulatory system.
The main mechanisms that can increase cardiac output are:
- heart rate: how fast the heart is beating
- stroke volume: the volume of blood pumped out of the ventricle during contraction

Question 26

(see exam for diagram)
The diagram below shows a flow volume loop from a healthy patient.
On the same diagram, trace the expected results for a patient with emphysema. Indicate the parameters that have changed for the patient with emphysema, and the parameters that have not changed.

Answer 26

(see notes)

• decrease PEF
• decrease FVC
• increase PIF

Question 27

Explain the pathological processes that occur inside the lungs to cause emphysema and the associated difficulty with breathing.

Answer 27

In emphysema, there is an increase in enzymatic activity resulting in the breakdown of lung elastic. This reduces the elastic recoil and thus decreases the elastic fibres and surface tension. This results in difficulty during expiration as it creates air trapping increasing residual volume.

Question 28

How does the residual volume in an asthmatic patient compare with a healthy patient?

Answer 28

The residual volume in asthmatic patients is increased compared to a healthy patient. This is because there is an increased airway resistance resulting in increased loss of pressure in small airway and thus resulting in early small airway closure resulting in decreased FVC and increased RV.

Question 29

Briefly discuss THREE (3) types of sensation (modalities) that the human body is able to perceive.

Answer 29

?

Question 30

A child is admitted to hospital with a severe asthma attack. The physician on duty quickly has the child nebulised with salbutamol, a short-acting medication, commonly found in blue inhalers carried by asthmatics. What is the mechanism of action for salbutamol?

Answer 30

short term stimulation of beta 2 receptors on smooth muscle lining the bronchioles
effective in early phase asthma

Question 31

A child is admitted to hospital with a severe asthma attack. The physician on duty quickly has the child nebulised with salbutamol, a short-acting medication, commonly found in blue inhalers carried by asthmatics. Why is a nebuliser used for this child instead of the usual blue puffer?

Answer 31

?

Question 32

A child is admitted to hospital with a severe asthma attack. The physician on duty quickly has the child nebulised with salbutamol, a short-acting medication, commonly found in blue inhalers carried by asthmatics. Why doesn’t the physician consider administering adrenaline to the child via nebuliser?

Answer 32

Adrenaline can work in an asthma attack as it is an agonist on the Beta2 receptors in the bronchial smooth muscle (dilates vessels). However, adrenaline also can work very well on Beta1 receptors as in the heart tissue, leading to a rapid heart rate as well as effects on the blood vessels. Adrenaline can help but if the patient has heart issues, this may not be a good drug of choice within the whole body.

Question 33

A child is admitted to hospital with a severe asthma attack. The physician on duty quickly has the child nebulised with salbutamol, a short-acting medication, commonly found in blue inhalers carried by asthmatics. What would you advise the parents of this child regarding their child’s medical condition to reduce the likelihood that a future emergency room visit will be necessary?

Answer 33

?