Biology

Q.

The (i)___, controls both the heart rate and the stroke volume. There are two separate nerves from the cardiovascular centre to the sinoatrial node: the (ii)___, to speed up the heart rate and the (iii)___, to slow it down. (i) receives information from special cells called (iv)___, present in the aortic arch and in the carotid sinus.

1. (i) Cardiac centre, (ii) Parasympathetic system, (iii) Sympathetic system, (iv) Baroreceptors

2. (i) Cardiac centre, (ii) Sympathetic system, (iii) Parasympathetic system, (iv) Baroreceptors

3. (i) Sympathetic system, (ii) Baroreceptors, (iii) Cardiac centre, (iv) Parasympathetic system

4. (i) Baroreceptors, (ii) Sympathetic system, (iii) Parasympathetic system, (iv) Cardiac centre

Q.

Go through the following statements: (i) The stroke volume multiplied by heart rate gives the cardiac output. (ii) The second heart sound is associated with the closure of semilunar valves. (iii) Heart failure is the same as cardiac arrest or a heart attack. Which of these are correct?

1. (i) & (ii)

2. (ii) & (iii)

3. (i) & (iii)

4. All are correct

Q.

If a person is suffering from blood loss, the cardiac output will __(i)____ , blood vessels will _(ii)_____ and the heartbeat will be ___(iii)____.

1. (i) increase, (ii) constrict, (iii)increased

2. (i) decrease, (ii)constrict, (iii) increased

3. (i) increase, (ii) dilate, (iii) decreased

4. (i) decrease, (ii)dilate, (iii) increased

Q.

If the blood pressure is too low, the cardiovascular control centre in the medulla oblongata attempts to compensate by causing a/an _______.

1. Decreased cardiac output

2. Increased contractility of the myocardial cells

3. Systemic arteriolar dilation

4. Decreased heart rate

Q.

Which of the following nerves causes the adrenal medulla to release epinephrine and norepinephrine and also speed up body activities?

1. Parasympathetic

2. Sympathetic

3. Somatic

4. Autonomic

Q.

Which of the following is NOT correctly matched?

1. Cardiac centres - Cardiovagal and Vasomotor

2. Baroreceptors - Present in aorta and carotid

3. Positive Inotropic action - Increases the firing rate of Sinoatrial node

4. Negative Chronotropic effect - Increases the force of contraction of heart

Q. Compared to blood our lymph has

1. more RBCs and less WBCs
2. Plasma without proteins
3. more WBCs and no RBCs
4. no plasma

Q.

The thoracic and right lymphatic ducts return lymph to the ______.

1. Abdominal cavity

2. Heart ventricles

3. Dorsal aorta

4. Subclavian veins

Q.

Role of spleen of mammals is to

1. Assist kidneys

2. Act as a haempoietic tissue

3. Secrete digestive enzymes

4. Produce angiotensinogen

Q.

Which of the following is/are the composition of the fluid in lacteals?

1. Fats and chyme

2. Chyme and chyle

3. Chyme and lymph

4. Lymph and fat