Blood Vessels

Our circulatory system is made up of blood vessels that carry blood throughout the body. There are three main types of blood vessels: arteries, veins, and capillaries.

Arteries

Arteries are the blood vessels that carry oxygen-rich blood away from the heart to the rest of the body. They have thick, muscular walls that allow them to withstand the high pressure of the blood being pumped from the heart.

Veins

Veins are the blood vessels that carry oxygen-poor blood back to the heart. Unlike arteries, veins have thinner walls and contain valves to prevent the backward flow of blood. This helps the blood return to the heart, especially from areas of the body farthest from the heart, such as the legs.

Capillaries

Capillaries are tiny blood vessels that connect arteries to veins. They are where the exchange of oxygen, nutrients, and waste products occurs between the blood and the body's tissues. Capillary walls are only one cell thick, allowing for efficient exchange of these substances.

Study Guide

1. What are the three main types of blood vessels? Arteries, Veins, Capillaries
2. Which blood vessels carry oxygen-rich blood away from the heart? Arteries
3. What is the purpose of valves in veins? Prevent the backward flow of blood
4. Where does the exchange of oxygen, nutrients, and waste products occur? Capillaries

Understanding the structure and function of blood vessels is essential for comprehending how our circulatory system works to distribute oxygen and nutrients throughout the body. Keep exploring and learning about the amazing network of blood vessels in our bodies!