1. The Circulatory System
Human Body Systems
The Circulatory System

2. The Heart
Organ made of cardiac muscle tissue.

3. Chambers of the Heart
The heart contains four compartments called chambers.
The two upper chambers are called the right and left atriums.
The two lower chambers are called the right and left ventricles.

4. Atrium
Atrium
Ventricle
Ventricle

5. Sections of the Circulatory System
Pulmonary Circulation – The flow of blood through the heart to the lungs and back to the heart.
Oxygen Poor Blood
Picks up oxygen from the LUNGS
Oxygen Rich Blood

6. Sections of the Circulatory System
Systemic Circulation – Oxygen-rich blood moves to all of your organs and body tissues, except the heart and lungs, and oxygen-poor blood returns to the heart. This is the largest of the three sections of your circulatory system.
Oxygen Rich Blood
Oxygen Poor Blood
Gives Oxygen to Body Cells

9. carry is rich with OXYGEN
Blood Vessels
Arteries – Blood vessels that carry blood away from the heart. They have thick, elastic walls made of connective tissue and smooth muscle tissue.
Arteries are RED
because the blood they
carry is rich with OXYGEN

10. Blood Vessels
The right ventricle of the heart is connected to the pulmonary artery (moves blood toward the lungs).
The left ventricle of the heart is connected to the aorta (move blood toward other body tissues).

11. Aorta
Pulmonary Artery
Atrium
Atrium
Ventricle
Ventricle

12. Blood Vessels
Veins – Blood vessels that carry blood back to the heart. Veins have one-way valves that keep blood moving toward the heart.
Veins are BLUE
because the blood they
carry is OXYGEN poor

13. Blood Vessels
The superior vena cava returns blood from your head and neck.
The inferior vena cava returns blood from your abdomen and lower body.

14. Superior Vena Cava
Aorta
Pulmonary Artery
Atrium
Atrium
Ventricle
Ventricle
Inferior Vena Cava

15. Blood Vessels
Capillaries – Arteries and veins are connected by microscopic blood vessels. The walls of capillaries are only one cell thick. Nutrients and oxygen diffuse from body cells into capillaries.
Video

16. Blood Blood carries oxygen from your lungs to your body cells.
Carbon dioxide diffuses from your body cells into your blood. Your blood carries carbon dioxide to your lungs to be exhaled.
Blood carries oxygen because of a special protein called hemoglobin. Iron in hemoglobin helps it to carry the oxygen.

17. Blood
Blood is a tissue made of plasma, red and white blood cells, and platelets.
Blood is 55% plasma, 45% red blood cells, and <1% platelets and white blood cells.

18. Blood Demo
Blood group A If you belong to the blood group A, you have A antigens on the surface of your red blood cells and B antibodies in your blood plasma.
Blood group B If you belong to the blood group B, you have B antigens on the surface of your red blood cells and A antibodies in your blood plasma.
Blood group AB If you belong to the blood group AB, you have both A and B antigens on the surface of your red blood cells and no A or B antibodies at all in your blood plasma.
Blood group 0 If you belong to the blood group 0 (null), you have neither A or B antigens on the surface of your red blood cells but you have both A and B antibodies in your blood plasma.