Capillaries

Q. Which of the following is the smallest blood vessel?

1. Arteries
2. Veins
3. Nerves
4. Capillaries

Q.

Why arteries have thick, elastic walls, while veins have thin walls?

1. Arteries are under more pressure, while veins are under less pressure.

2. Arteries are big, while veins are small.

3. Arteries have valves, while veins don't have valves.

4. None of these.

Q. Which of the following are characteristics of veins?

1. Carry oxygen rich blood
2. Thin walled
3. They have valves
4. Carry carbon dioxide rich blood

Q. The exchange of materials between the blood and the interstitial fluid occurs only in the

1. Veins
2. Capillaries
3. Arteries
4. Arterioles

Q.

Why arteries have thick, elastic walls, while veins have thin walls?

1. Arteries are under more pressure, while veins are under less pressure.

2. Arteries are big, while veins are small.

3. Arteries have valves, while veins don't have valves.

4. None of these.

Q. Explain briefly three major types of blood vessels in human beings?

Q. Hiccough (hiccup) is due to activity of

1. Intercostal muscle
2. Food in air tract
3. Diaphragm
4. Inadequate oxygen in environment