2nd Year Biology Chapter 2 Test02. Blood Circulatory System of Man

Q1. Multiple choice questions (Attempt all · 10 × 1 = 10)

1. The heart is stopped during open heart surgery to:
   1. Reduce blood sugar
   2. Keep lungs functioning
   3. Remove cholesterol
   4. Allow repair of heart muscle
2. The approximate diameter of capillaries is:
   1. 0.2 mm
   2. 7 to 9 μm
   3. 1 mm
   4. 5 mm
3. During the period of ejection in the cardiac cycle, the atrioventricular valves are ……… and the semilunar valves are ………
   1. closed, closed
   2. closed, open
   3. open, closed
   4. open, open
4. What produces systolic blood pressure?
   1. contraction of the right atrium
   2. ontraction of the right ventricle
   3. ontraction of the left atrium
   4. contraction of the left ventricle
5. The process in which a detached clot or other mass is carried by the bloodstream to another site is:
   1. Thrombosis
   2. Embolism
   3. Vasoconstriction
   4. Atherosclerosis
6. The rhythmic beating of cardiac muscle in mammals is initiated by:
   1. atrio-ventricular node
   2. parasympathetic nervous system
   3. Purkinje tissue
   4. sino-atrial node
7. Which cells are present in lymph nodes to engulf debris and destroy germs?
   1. Red blood cells
   2. Platelets
   3. Macrophages
   4. Plasma cells
8. Precapillary sphincters control blood flow according to:
   1. Body temperature
   2. Metabolic needs of the tissue
   3. Heart rate
   4. Blood pressure in arteries
9. Veins differ from arteries in that they:
   1. Have thick walls
   2. Carry blood away from the heart
   3. Lack endothelium
   4. Possess valves
10. Bradycardia means a heart rate of:
    1. More than 100 beats per minute
    2. 60–80 beats per minute
    3. Less than 40 beats per minute
    4. Exactly 72 beats per minute