Blood Vessels

Which type of blood vessel carries blood away from the heart?

• Veins

• Capillaries

• Arteries

• Alveoli

What is the main function of veins?

• To carry oxygen-rich blood from the heart to the body

• To exchange oxygen and carbon dioxide

• To carry blood towards the heart

• To pump blood through the body

Which of the following blood vessels have thin walls for the exchange of gases?

• Arteries

• Veins

• Capillaries

• Aorta

What helps veins carry blood back to the heart, even against gravity?

• Thick walls

• Valves

• High pressure

• Oxygen-rich blood

Where does the exchange of oxygen and carbon dioxide take place?

• Arteries

• Capillaries

• Veins

• Atria

What is the name of the largest artery in the body?

• Pulmonary artery

• Aorta

• Vena cava

• Coronary artery

Which blood vessel carries deoxygenated blood from the body to the heart?

• Pulmonary vein

• Aorta

• Vena cava

• Capillaries

Assertion (A): Arteries have thicker walls as compared to veins.

Reasoning(R): The arteries pushes the blood towards the body with force.

• A is true and B is the correct explanation for A

• A is true but B is not the correct explanation for A

• A is true and B is false.

• B is true and A is false

Assertion (A): Blood capillaries ensure that tissues get enough oxygen.

Reasoning (R): Thin walls of blood capillaries facilitate the exchange of oxygen and nutrients with tissues

• A is true and R is the correct explanation of A

• A is true but R is not the correct explanation of A

• A is true and R is false.

• A is false and R is true.

Answer explanation

Capillaries are tiny blood vessels that facilitate the exchange of oxygen and nutrients with tissues. Their thin walls allow oxygen to diffuse easily from the blood into surrounding cells, ensuring adequate oxygen supply.

Assertion (A): Veins have valves to prevent backflow of blood.

Reasoning (R): This results in varicose veins and other circulatory issues.

• A is true and R is the correct explanation of A

• A is true but R is not the correct explanation of A

• A is true and R is false

• A is false and R is true