Question

The smallest blood vessel in the body is
A. Capillary
B. Artery
C. Vein
D. Vena cava

Answer 1

Hint: This type of blood vessels is so small that red blood cells move single-file through these vessels. This blood vessel also connects arteries and veins.

Complete Answer:
- Our body has a network of channels. These channels are called blood vessels. Blood vessels circulate blood throughout the body and help keep the blood flowing to and from the heart. Various kinds of blood vessels are found in our body. The three major blood vessels are: Veins, arteries, and capillaries.
- Capillaries are the microscopic blood vessels where the exchange of important substances and wastes occurs. These are the smallest blood vessels.
- A capillary wall permits easy exchange of minerals between the blood and body cells through the process of diffusion.
- The large blood vessels that carry away the oxygen rich blood from the heart are called arteries. These blood vessels are thick-walled, strong, durable, and elastic. They are able to withstand high pressures exerted by blood as it is pumped by the heart.
- Vein is the largest blood vessel. Veins carry oxygen poor blood back to the heart.
The vena cava is the two main veins that bring blood to the right atrium. The upper vena cava transports blood from the arm and the brain to the tip of the right atrium.The inferior vena cava transports blood from the legs and the abdominal cavity to the bottom of the right atrium.

Thus, the correct answer is option A i.e., Capillary.

Note: A blood vessel is a tube-like structure that carries blood. Oxygen-rich blood leaves the left side of the heart and reaches the aorta. The aorta is separated into arteries, which gradually branch into smaller arterioles. Arterioles deliver blood and oxygen to the capillaries.