Question

Assertion:
Arteries carry blood from various body organs to the heart
Reason:
Veins carry blood from various body organ to the heart
(a)Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
(b)Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
 (c)Assertion is correct but Reason is incorrect
(d) Assertion is incorrect but Reason is correct

Answer 1

Hint: Arteries are the blood vessels that are muscular tubes lined with smooth tissue. It consists of three layers: the intima, the media, and the adventitia. Veins are the blood vessels which consist of three main layers. The outer layer is known as connective tissue or tunica adventitia, the middle layer is of smooth muscle known as tunica media and the inner layer is made up of endothelial cells which are known as tunica intima.

Complete answer:
Arteries carry oxygenated blood from the heart to different organs of the body. Veins carry oxygenated blood from various body organs to the heart. The pulmonary artery carries the deoxygenated blood from the heart to the lungs whereas the pulmonary vein carries oxygenated blood from the lungs to the heart. An artery carries blood away from the heart. The walls of arteries can expand and contract. The main artery which leaves the heart is known as the aorta. Some veins gather blood from capillary beds into veins and are known as venules which are smaller structures. Therefore, the assertion is incorrect but the reason is correct.

Additional Information: The fluid which fills the arterial system is known as effective arterial blood volume. Arteries are responsible for the transportation of nutrients and oxygen to deliver to all parts of the cell. It also helps to remove carbon dioxide and waste products. It helps in maintaining the optimum blood pH and circulation of protein. The outermost layer of an artery which is known as tunica externa consists of collagen fibers and elastic tissues. Its boundary is not well defined and considered when it meets the connective tissue. The tunica media is the middle laya which is composed of smooth muscle, collagen fibers, and elastic tissues. The innermost layer is involved in direct contact with the flow of blood and is known as tunica intima. Veins are less muscular and are present closer to the skin. It prevents the backflow of blood by valves. They are known as capacitance vessels due to the most amount of blood volume which is present in them around 60%. The most common disorder of the venous system is the insufficiency of veins. Deep vein thrombosis happens when there is a blood clot in a deep vein.
So, the correct answer is 'Assertion is incorrect but Reason is correct'.

Note: All veins take the blood back to the heart but portal veins carry blood between capillary beds. The hepatic portal vein carries blood from capillary beds in the digestive tract to the capillary beds in the liver. The damage to the hepatic portal vein can be dangerous.