Assertion (A): | The sino-atrial node is normally the pacemaker of the human heart. |
Reason (R): | It is the only auto-excitable part of the nodal tissue of the human heart. |
1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
3. | (A) is True but (R) is False. |
4. | Both (A) and (R) are False. |
I: | The atria also undergo systole |
II: | The atrioventricular valves get closed |
III: | The semilunar valves are forced open |
Column I | Column II | ||
A. | Neutrophils | P. | Phagocytosis |
B. | Basophils | Q. | Inflammatory reactions |
C. | Lymphocytes | R. | Immune responses |
D. | Thrombocytes | S. | Coagulation of blood |
A | B | C | D | |
1. | P | Q | R | S |
2. | Q | P | S | R |
3. | R | S | P | Q |
4. | S | R | Q | P |
1. | Mollusks and arthropods have closed circulatory system |
2. | All vertebrates possess a muscular chambered heart |
3. | In fishes, the heart pumps out deoxygenated blood |
4. | The left atrium receives oxygenated blood in amphibians and reptiles |
1. | is a bone marrow stem cells committed to produce RBCs |
2. | is the megakaryocyte |
3. | is the commonest WBC and is phagocytic |
4. | is responsible for acquired immunity in humans |
I: | SA node is the natural pacemaker of the human heart. |
II: | SA node is the only part of that nodal musculature that is auto-excitable. |
1. | Only I is correct |
2. | Only II is correct |
3. | Both I and II are correct |
4. | Both I and II are incorrect |
I: | The type of antigen present on the RBCs of a person with blood group type A is A |
II: | The type of antibodies present in the plasma of a person with blood group type A is anti-A |
1. | Only I is correct |
2. | Only II is correct |
3. | Both I and II are correct |
4. | Both I and II are incorrect |
I: | Neural signals through sympathetic nerves |
II: | Neural signals through parasympathetic nerves |
III: | Adrenal medullary hormones |
1. | Only I and II |
2. | Only I and III |
3. | Only II and III |
4. | I, II and III |
1. | Neutrophils and monocytes are the main phagocytic cells in human blood. |
2. | Mature RBC does not have a nucleus and is biconcave disc-shaped. |
3. | A person with type A blood will have anti-B antibodies in his plasma. |
4. | Erythroblastosis foetal occurs when an Rh +ve mother is carrying an Rh –ve foetus. |
COLUMN I | COLUMN II | ||
A | P wave on an ECG | P | Ventricluar depolarization |
B. | QRS complex on an ECG | Q | Atrial depolarization |
C. | First heart sound | R | Closure of semilunar valves |
D. | Second heart sound | S | Closure of atrioventricular valves |
A | B | C | D | |
1. | Q | P | S | R |
2. | P | Q | S | R |
3. | P | Q | R | S |
4. | Q | P | R | S |