Physiologi I - Question Bank

9. Vasodilators produced by the endothelium include: 1. endothelium derived relaxing factor (EDRF), 2. nitric oxide (NO), 3. prostacyclin (PGI 2), 4. endothelin, 5. thromboxane (TXA2)

a. 1, 2 and 3 are true

b. only 1 is true

c. 2, 3, 4 and 5 are true

d. 1, 4 and 5 are true

e. 1, 2, 3, 4 and 5 are true

2. Capillary permeability is increased by:

a. angiotensin II

b. adrenaline

c. calcium

d. vasopressin

e. histamin

6. Which is NOT correct regarding the heart?

a. excitation begins in the sinoatrial node

b. excitation of the ventricle begins at the apex and spread to the base

c. depolarization occurs from epicardium to endocardium

d. stimulation of the left vagus nerve slows the sinoatrial node

e. the branches of the His-bundle connect the atrioventricular node to the Purkinje's fibres of the ventricle

1. Hyperventilation:

a. increases cerebral blood flow

b. increases ionized calcium concentration in the serum

c. causes hypocapnia

d. causes metabolic alkalosis

e. increases cardiac output

4. Dilatation of the peripheral arterial blood vessels can be caused by:

a. thromboxane A2

b. GTP

c. endothelin

d. Arg-vasopressin

e. nitric oxide.

8. Valsalva maneuvre causes:

a. increased peripheral resistance

b. drop in blood pressure

c. tachycardia

d. increased blood volume in systemic circulation

e. all are true

3. Compared with intracellular fluid, extracellular fluid has:

a. a greater osmolarity

b. a higher sodium concentration

c. a lower chloride ion concentration

d. a larger volume

e. a higher potassium ion concentration

5. Which of the followings is NOT true about the resistance to blood flow in the vessels?

a. It is dependent on the haematocrit.

b. It depends on the thickness of the vessel wall.

c. It is directly proportional to the length of the vessel.

d. It is directly proportional to the pressure drop along the vessel.

e. It is inversely proportional to the fourth power of the radius of the vessel.

7. Which of the followings is true about renal circulation?

a. it accounts for 20-25% of the cardiac output in rest

b. it is regulated predominantly by the autonomic nervous system

c. in an adult man, renal blood flow is about 120 ml/min

d. macula densa cells are found in the efferent arteriolar wall

e. blood supply to the cortex is derived mainly from the vasa recta

10. Local vasodilatation is caused by, EXCEPT:

a. increased lactate concentration in the striated muscle

b. sudden decrease of skin temperature

c. increased hydrogen ion concentration

d. increased potassium ion concentration

e. reduced oxygen tension in the systemic circulation