Chapter 4: Circulation (Cardiovascular System)

Chapter 4: Circulation (Cardiovascular System) Mr. Gagnon

4.1 The Body’s Transportation System Key Terms: Cardiovascular System Atrium Ventricle Vena Cava / Aorta Pulmonary Arteries/Veins Capillaries Key Concepts: What is the function of the cardiovascular system? What role does the heart play in the cardiovascular system? What path does the blood take through the c.s.?

Movement of Materials • The cardiovascular system carries needed substances to cells and carries waste products away from cells. • There are 3 major materials moved: • Needed Materials- oxygen, glucose, etc. • Waste products- Carbon dioxide • Disease Fighters- White blood cells (WBC) that fight disease causing microorganisms.

What is the Force of the Movement? • The Heart is the muscle that pumps blood throughout the body. • Each time a heart beats it pushes the blood through the cardiovascular system.

What Are the Structures of the Heart? • The Atrium receives blood into the heart. • The Ventricle pumps blood out of the heart. • The Valves separate the atriums and ventricles. • The body’s Arteries are blood vessels that carry blood away from the heart. • The body’s Capillaries exchange materials from the blood to the body cells. • The body’s Veins bring blood back to the heart.

The 2 Blood Loops in the Body Loop 1: Heart to Lungs Loop 2: Heart to Body

The Loops Loop 1: Loop 2: Blood is pumped from the heart (oxygenated) throughout the body, and then returns again to the heart (deoxygenated). • Blood travels from the heart to the lungs (deoxygenated). • CO2 leaves the blood and goes into the lungs. • O2enters the blood and the blood returns to the heart (oxygenated).

Anatomical Structure of the Heart Bi-Cuspid Valve Tri-Cuspid Valve Septum

4.2 Blood Vessels Key Terms: Arteries Veins Capillaries Coronary Arteries Pulse Blood Pressure Key Concepts: What are the functions of arteries, capillaries, and veins? What causes blood pressure?

When blood leaves the heart it travels through the arteries. The arteries carry blood away from the heart. The aorta sends blood through coronary arteries, the first set of arteries leaving the heart. Arteries

Arteries are generally very thick. • Arteries consist of 3 layers: • Innermost: smooth tissue that allows the blood to flow smoothly. • Middle: muscle tissue. • Outer: flexible connective tissue. Arteries

You may check your pulse by lightly pressing on you wrist or neck. • When the ventricles of the heart contract, they send a spurt of blood out of the heart. • The artery walls expand to allow the blood flow and then narrow after it passes. The muscles in the middle wall regulate blood flow. The muscles contract to allow less blood flow to organs not active at the moment. When you eat the arteries going to the stomach and intestines relax to allow more blood flow to fuel the digestive process. Arteries

After blood flows through the arteries, it goes to the capillaries. In the capillaries, materials are exchanged between blood and body cells. The materials are exchanged via diffusion. Diffusion is the process by which molecules move from an area of high concentration to low concentration. Example: There is a higher O2 level in the blood than in the cell. The O2 goes into the cell and CO2leaves the cell. Capillaries

After blood goes through the capillaries, blood flows through the veins to return to the heart. Vein walls are thinner than artery walls, but still have 3 similar layers. • Blood flows though veins via 3 ways: • 1- Muscles within the vein contract. • 2- Veins are located near skeletal muscles and their contraction pushes the blood along. • 3- Larger veins have valves, making sure the blood does not flow backwards. Veins

Pressure is the force that something exerts over a given area. The blood flow exerts force against the walls of blood vessels. Blood pressure is caused by the force by which the ventricles contract. Blood pressure is highest in the arteries and lowest in the veins. Blood pressure is measured by an instrument called a sphygmomanometer. Blood Pressure

4.3 Blood and Lymph Key Terms: Plasma Red Blood Cells White Blood Cells Platelets Hemoglobin Fibrin Blood Transfusion Lymph Lymph Nodes Key Concepts: What are the 4 components of blood? What determines the type of blood that a person can receive in transfusion?

Blood consists of: • Plasma • Red Blood Cells • White Blood Cells • Platelets Blood

Plasma is the liquid part of the blood. 10% is dissolved materials. 90% is water. • The dissolved materials are molecules from digested foods like glucose and fats. • Chemical messengers are also carried in the plasma. • Proteins in the blood: • Help regulate water. • Created by WBC to fight disease. • Work with platelets to form blood clots. Plasma

RBC are primarily used to transport O2 from the lungs to the rest of the body. CO2 is carried primarily by plasma, however some hemoglobin carry CO2. RBC’s are mostly made of hemoglobin, which is an iron-containing protein that binds chemically to oxygen molecules. Hemoglobin turns bright red when oxygenated, dark red when deoxygenated. Red Blood Cells (RBC)

WBC’s are the body’s disease fighters. • WBC’s have different jobs: • Alert others of a foreign object. • Produce chemicals to fight invaders. • Surround and kill the invader. There are fewer WBC’s than RBC’s at a 1 : 500-1,000 ratio. WBC’s are larger than RBC’s WBC’s have nuclei, RBC’s don’t. WBC’s live for months and even years. White Blood Cells (WBC)

Platelets are cell fragments that are found in the blood and form blood clots. When platelets stick together to form a blood clot they release a chemical, creating a reaction that forms fibrin. Fibrin weaves fibers creating a net that collect and stops blood cells. Platelets

Why would you need to know your blood type? • If you lose a lot of blood, you may need a blood transfusion. • A blood transfusion is the transference of blood from one person to another. • There are 3 types of blood: • Type A: Can receive blood from A and O. • Type B: Can receive blood from B and O. • Type AB: Can receive blood from A, B, AB, and O. • Type O: Can receive blood only from O. Blood Types

Blood Types: • Blood types are determined by marker molecules found on the exterior of the blood (RBC’s). • Someone may become ill if a different type of blood is transmitted into the body.

The Lymphatic System: • The lymphatic system is a network of vein-like vessels that returns the fluid that leaks out of the cardiovascular system back into the blood stream. • Lymph is the fluid in the lymphatic system that consists of water and dissolved materials (ie: glucose). • Lymph nodes filter the lymph, trapping bacteria and other microorganisms that could cause disease.

4.4 Cardiovascular Health Key Terms: Artherosclerosis Heart Attack Cardiac Arrest Hypertension Key Concepts: - What behaviors can help maintain cardiovascular health?

Cardiovascular Disease: • Atherosclerosis is a condition in which an artery wall thickens as a result of the buildup of fatty materials. • Cholesterol, a waxy fat like substance sticks to artery walls and makes a clog in the artery. • A heart attack occurs when blood flow to part of the heart muscle is blocked. • Cardiac arrest is when the heart seizes to pump blood effectively.

Cardiovascular Disease: • Hypertension is a disorder in which a person’s blood pressure is consistently higher than normal (>140/90). • In order to reduce your chance of cardiovascular disease you should: • Exercise regularly • Eat a well balanced diet • Don’t smoke

Chapter 4: Circulation (Cardiovascular System)