Functions of the Cardiovascular System Cardiovascular system is also known as the circulatory system Main functions are delivering materials to cells and carrying waste away Blood contains cells that fight disease Delivering materials The heart continually pumps the blood in your blood vessels throughout your body Example: blood picks glucose from your digestive system and brings it to cells where it is used for energy Removing wastes Transports wastes form your cells Example: when your cells break down glucose for energy carbon dioxide is released as a waste product

The Heart One loop leads from your heart to your lungs Where the blood releases carbon dioxide, picks up oxygen and returns it to your heart Second loop circles through to the rest of your body, where the blood delivers oxygen and nutrients and picks up waste

Structure of the Heart Has 2 chambers Upper chamber- atrium (receives blood entering the heart) Lower chamber- ventricle (receives blood from atria, then pumps blood out of the heart) The rate at which your heart muscles contract is regulated by the pacemaker

Blood Vessels Arteries Blood vessels that carry blood away from the heart Largest artery in the body is the aorta Capillaries Branch from the smallest arteries Smallest blood vessels in the body Veins Large, thin walled blood vessels that carry blood to the heart Valves inside the veins prevent blood from flowing backward

Blood Pressure The force with which blood pushes against the walls of your blood vessels Systolic is the pressure when the ventricles contract Diastolic is the pressure when the ventricles are relaxed Normal blood pressure In the range of 90/60 to 119/79 Low blood pressure Lower than 90/60 High blood pressure Blood pressure is consistently 140/90 or greater (known as hypertension)

Blood Plasma The liquid component of blood Red blood cells The cells that carry oxygen from the lungs to tall the parts of body The reaction between oxygen and the iron in hemoglobin gives blood its bright red color White blood cells Helps protect you against diseases and foreign substances Platelets Cells fragments that play an important role in the blood clotting process