Cardiovascular System - Chapter 15, Part 2

What do arteries carry away from the heart?

• Waste products

• Carbon dioxide

• Oxygen-rich blood

• Nutrients

Why do veins appear blue when viewed through the skin?

• Due to a trick of light and the way light wavelengths are absorbed

• Due to the presence of blue cells in the blood

• Because the blood in veins is blue

• Because veins are made of blue tissue

What special feature do veins have to help blood return to the heart?

• Elastic membranes

• Valves

• Thicker walls

• Higher pressure

How do muscles help veins in blood circulation?

• By providing oxygen to the blood

• By increasing blood pressure

• By absorbing waste products

• By contracting and pushing blood through the veins

What happens during vasodilation?

• Blood vessels constrict to reduce blood flow

• Blood pressure decreases significantly

• Blood vessels expand to increase blood flow

• Blood vessels become blocked