Histamine, serotonin and heparin are secreted by:
(1) Thrombocytes
(2) Lymphocytes
(3) Monocytes
(4) Basophils
B and T forms, responsible for the immune response are the type of:
(1) Thrombocytes
(2) Lymphocytes
(3) Eosinophils
(4) Granulocytes
Assertion : In mollusca, circulatory system is of closed type.
Reason : The blood of mollusca contains haemoglobin
Assertion : Histamine is involved in allergic and inflammatory reactions.
Reason : Histamine is a vasodilator
Assertion : Heart valves resemble swing doors in action.
Reason : Valves are present in the heart chamber, at the opening of the heart into large arteries and veins.
Assertion : Closed circulatory system is more effective than open type.
Reason : The closed circulatory system considerably enhances the speed, precision and efficiency of circulation.
Assertion : Cardiac output rises during exercise.
Reason : Cardiac output helps in less oxygen consumption.
Assertion : EEG is of immense diagnostic value in the cardiac diseases.
Reason : Defects in cardiac functions can be reflected in changes in the pattern of electrical potentials recorded in the EEG.
Assertion : An artificial pacemaker can replace the sinoatrial node of heart.
Reason : This is because, an artificial pacemaker is capable of stimulating the heart electrically to maintain its beats.
Assertion : Mixing of oxygenated and deoxygenated blood occurs in reptilian and amphibian hearts.
Reason : This happens because of the incomplete partitioning of the auricle.