Which of the following are NOT a part of the circulatory system?

The correct answer is Villi.

• Capillaries are called very tiny blood vessels.
• The Capillaries expand like a mesh in the whole body.
• Through these capillaries, blood is transported to all parts of the whole body.
• The arteries are the blood vessels that carry blood from the heart.
• All arteries carry oxygen-rich blood, except for pulmonary and avascular arteries.
• A tube that carries blood from the body to the heart and returns back is called a 'vein'.
• 'Villy' is a structure found in the intestine that helps to absorb nutrients from the food eaten.