Circulatory System

Functions of the Circulatory System Transport of oxygen, nutrients and waste products Helps regulate body temperature

Components Heart Blood Blood Vessels Primary organ that pumps blood through the entire body Blood This nutrient rich liquid has everything your cells need to survive It also collects the waste your cells produce Blood Vessels Roads through the body that carry the blood to every single cell Arteries Capillaries Veins

Central Organ The Heart - muscular organ that pumps blood through a network of blood vessels Myocardium- major muscular portion of the heart Pericardium- a thick membranous enclosure that protects the heart

Heart Anatomy A septum (wall) vertically divides into two sides Right- pumps blood to the lungs Left- pumps blood to the other parts of the body Upper chambers- atrium Lower chambers- ventricles

Flow of Blood in the Heart Coming from the body, blood is deoxygenated (low O2, rich in carbon dioxide) enters the: 1. Superior and Inferior Vena Cava 2. Into the Right atrium 3. To the Right Ventricle 4. Through the Pulmonary arteries 5. To the capillaries of the lungs to exchange CO2 for O2

Flow of Blood in the Heart 6. From the lungs - the blood is rich in O2 7. Through the pulmonary veins into the Left Atrium 8. To the Left Ventricle 9. Through the Aorta to the rest of the body

Heart Valves Valves- Flap of tissue that open in only one direction. Valves prevent blood from flowing backwards.

Heart Superior Vena Cava Aorta Pulmonary Arteries Pulmonary Veins Large vein that brings oxygen-poor blood from the upper part of the body to the right atrium Aorta Brings oxygen-rich blood from the left ventricle to the rest of the body Pulmonary Arteries Bring oxygen-poor blood to the lungs Pulmonary Veins Bring oxygen-rich blood from each of the lungs to the left atrium Left Atrium Pulmonary Valve Prevents blood from flowing back into the right ventricle after it has entered the pulmonary artery Aortic Valve Prevents blood from flowing back into the left ventricle after it has entered the aorta Right Atrium Mitral Valve Prevents blood from flowing back into the left atrium after it has entered the left ventricle Tricuspid Valve Prevents blood from flowing back into the right atrium after it has entered the right ventricle Left Ventricle Inferior Vena Cava Vein that brings oxygen-poor blood from the lower part of the body to the right atrium Septum Right Ventricle

Blood Blood is 45% cells and 55% plasma Blood Cells: Blood Plasma: Red Blood Cells: carry oxygen White Blood Cells: fight disease Platelets: stop bleeding by scabbing Blood Plasma: 90% water 10% nutrients and hormones

Blood Vessels Vast network that keep the blood flowing in one direction Arteries and arterioles- carry blood away from the heart. Arteries are large, muscular vessels. They are strong and elastic which allow them to stretch as blood enters from the heart. Arterioles are smaller and less muscular in size and turn into capillaries

Blood Vessels 2. Capillaries – tiny blood vessels in networks that allows exchange of material through diffusion, between blood and cells in tissue Veinuoles- small blood vessels that carry deoxygenated blood away from the capillaries. They turn into veins. Veins- large blood vessels that carry deoxygenated blood to the heart. Veins have valves which prevents blood from flowing backwards.

Two Cardiovascular Pathways Pulmonary Circulation – blood that travels between the right side of the heart and lungs. Carbon dioxide diffuses out of the capillaries and oxygen diffuses in. Systemic Circulation – oxygenated blood that travels between the left side of the heart and all parts of the body except the lungs.

Blood Vessels Artery Vein Capillary Blood Pressure is the force the heart puts on your arteries Healthy is 120/80