THE CIRCULATORY SYSTEM TEACHER COPY THE CIRCULATORY SYSTEM • Also called the Cardiovascular System • Consists of the heart, blood vessels and blood • Has three functions 1. Carries needed substances to and from cells 2. Removes wastes from cells 3. Transports immune cells that help fight off bacteria, viruses and other disease causing cells. TC THE HEART • The heart is a muscular organ that pumps blood throughout the body. Each time it beats, it pushes blood through the blood vessels of the circulatory system • The right side of the heart is completely separated from the left side by a wall of tissue called the septum. • Each side has two compartments, or chambers an upper chamber and a lower chamber. TC THE HEART • Each of the two upper chambers are called an atrium which receives blood that comes into the heart • Each lower chamber is called a ventricle which pumps blood out of the heart. • The atria and ventricles are separated by valves which is a flap of tissue that prevents blood from flowing backward. TC TC Aorta- carries blood from the major vein from left ventricle to upper body to heart the body Artery- from Right atrium – heart to lungs receives blood from the body that is low in oxygen and high in carbon dioxide Right ventricle – pumps oxygen-poor Left Atrium- blood to the lungs Oxygen-rich blood moves from the lungs into the left major vein from atrium lower body to heart Left Ventricle- pumps oxygen-rich Septum- prevents oxygen-rich and oxygen-poor blood to the body blood from mixing BLOOD FLOW PATTERNS • Arteries are blood vessels that carry blood away from the heart. • Blood flows from arteries into capillaries which are tiny narrow vessels where substances like oxygen are exchanged between blood and body cells. • From capillaries blood flows into veins which are blood vessels that carry blood back to the heart TC BLOOD FLOW PATTERNS: LOOP 1 • There are two loops for blood flow. In the first loop blood travels from the heart to the lungs and then back to the heart. • The blood is oxygen poor but ____________________richCarbon dioxide which makes it _______________Dark Red in color • The blood reaches the lungs in capillaries where carbon dioxide moves into the lungs to be _______________Carbon dioxide while oxygen moves into the blood. • The oxygen rich blood is ________________Bright red in color and flows in a vein and back to the ________________heart TC BLOOD FLOW PATTERNS: LOOP 2 • In the second loop, blood is pumped from the heart throughout the body and then back to the heart. • Oxygen rich blood is pumped from the _____________Left ventricle in the heart and into the aorta. • The blood will flow to the capillaries in different parts of your body. • Oxygen moves out of the blood and into the body cells at the same time as carbon dioxide moves from the body cells to the blood. • Now the oxygen poor blood moves back to the _______________Right atrium of the heart. TC BLOOD FLOW PATTERNS TC BELL RINGER Complete this table Structure of Function Oxygen/Carbon Dioxide heart level in blood Right Atrium Receives blood Oxygen Low from the body Carbon Dioxide high Right Ventricle Pumps blood to the Oxygen Low lungs Carbon Dioxide high Left Atrium Receives blood from Oxygen high the lungs Carbon Dioxide low Left Ventricle Pumps blood to the Oxygen high body Carbon Dioxide low TC BELL RINGER Complete this table Blood Vessel Function Connected to which part of the heart Artery Carries blood away Right ventricle from the heart Left ventricle Capillary Narrow vessels where carbon dioxide and oxygen are exchanged Vein Carry blood back to Right atrium the heart Left Atrium TC BLOOD FLOW PATTERNS • When blood leaves the heart, it travels through arteries. The walls of arteries are very thick. Your __________pulse is caused by the expansion and relaxation of the artery wall. When you count your pulse rate you are counting your heart beat or rate. • In the capillaries materials are exchanged between the blood and body cell’s through the process of _______________diffusion where molecules move from higher to lower concentration. TC BLOOD AND LYMPH • Blood is made up of four components: • Plasma • Red blood cells • White blood cells • Platelets • 45% of the volume of blood is cells while the remaining 55% is plasma TC PLASMA • Plasma is the liquid part of the blood that helps transports the blood cells. • Water makes up 90% of plasma • Most of the carbon dioxide in blood is carried by the plasma PLATELETS • Platelets are cell fragments that help to form blood clots. • They stick to the site of the wound and release chemicals that start a chain reaction. • This series of reactions help produce a protein called fibrin that weaves tiny fibers in the wound. TC RED BLOOD CELLS (RBC) • RBC take up oxygen in the lungs and deliver it to cells in your body. • Produced in ______________Bone marrow • Made of hemoglobin which is an iron-containing protein that binds chemicals to oxygen molecules. • When hemoglobin binds to oxygen the cells become bright red, without oxygen the cells are dark red. • Mature RBS have no nuclei. TC WHITE BLOOD CELLS (WBC) • WBC are the bodies disease fighters. Some recognize the disease causing organisms and alert the body. Others produce chemicals to fight the invaders. Others surround and kill the organisms • Produced in ______________Bone marrow • They are larger and fewer than RBC and they TC THE LYMPHATIC SYSTEM • Is a network of vein like vessels that returns fluid to the bloodstream. • Fluid in the lymphatic system is called lymph which consists of water, dissolved materials and some WBC. • Lymph nodes filter the lymph and trap disease causing microorganisms. • Why do your lymph nodes swell when you are sick? TC .