Biology
Assertion (A): Capillaries are the finest blood vessels in the body, interconnecting arteries and veins.
Reason (R): The interconnection between arteries and veins is very significant because the exchange of water, nutrients, waste materials and respiratory gases occurs from arteries to veins and vice-versa through the capillaries only.
- Both A and R are true.
- Both A and R are false.
- A is true and R is false.
- A is false and R is true.
Related Questions
Assertion (A): None of the arteries carry deoxygenated blood in the human body.
Reason (R): Pulmonary artery carries deoxygenated blood from the right ventricle of the heart to the lungs.
- Both A and R are true.
- Both A and R are false.
- A is true and R is false.
- A is false and R is true.
Assertion (A): The walls of the atria are thinner as compared to those of the ventricles.
Reason (R): The atria are the 'receiving chambers' as they receive blood and ventricles are the 'distributing chambers' as they pump blood into lungs and the thickest blood vessel - Aorta.
- Both A and R are true.
- Both A and R are false.
- A is true and R is false.
- A is false and R is true.
Match the items in Column A with those in Column B.
Column A Column B (a) Sino atrial node (i) Deoxygenated blood (b) Pulmonary veins (ii) Between right atrium and ventricle (c) Pulmonary artery (iii) Pacemaker (d) Tricuspid valve (iv) Between left atrium and ventricle (e) Biscuspid valve (v) Oxygenated blood Name:
(a) The membranous structure which divides the heart into a right and a left portion.
(b) The structure responsible for starting electrical impulses that cause the heart to contract and relax in order to keep pumping blood.
(c) The scientist who identified different types of blood groups.