The Circulatory System Chapter Three

Learning Goal For students to learn more about the function of the circulatory system and its major components To learn the importance of tools in monitoring the circulatory system

Introduction The Circulatory system’s role is to transport blood, nutrients, and waste around the body It’s sort of like the TTC of the body

Main Functions of the Circulatory System It Transports gases (from the Respiratory System), nutrients, and waste materials (from the Digestive System) It regulates internal temperature and transports chemical substances that are vital to health from 1 part of the body to another It protects against blood loss from injury and disease-causing microbes, or any toxic substances introduced into the body

Major Components of the System Heart - Muscular organ that continuously pumps the blood through the body and generates Blood Flow Blood Vessels - System of Hollow tubes where blood moves through Blood - The Fluid that Transports nutrients, Oxygen, Carbon dioxide, and other things through the body

THE CIRCULATORY SYSTEM Functions: transports O2 and nutrients throughout the body carries away waste made up of blood, heart, vessels

THE CIRCULATORY SYSTEM HEART

THE CIRCULATORY SYSTEM HEART “pump”

THE CIRCULATORY SYSTEM ARTERIES HEART “pump”

THE CIRCULATORY SYSTEM ARTERIES BODY TISSUES HEART “pump”

THE CIRCULATORY SYSTEM ARTERIES BODY TISSUES O2 out CO2 in HEART “pump”

THE CIRCULATORY SYSTEM ARTERIES BODY TISSUES O2 out CO2 in HEART “pump” VEINS

THE CIRCULATORY SYSTEM ARTERIES BODY TISSUES O2 out CO2 in HEART “pump” VEINS VEINS

THE CIRCULATORY SYSTEM ARTERIES BODY TISSUES O2 out CO2 in LUNGS HEART “pump” VEINS VEINS

THE CIRCULATORY SYSTEM ARTERIES BODY TISSUES O2 out CO2 in LUNGS O2 in CO2 out HEART “pump” VEINS VEINS

THE CIRCULATORY SYSTEM ARTERIES ARTERIES BODY TISSUES O2 out CO2 in LUNGS O2 in CO2 out HEART “pump” VEINS VEINS

THE CIRCULATORY SYSTEM ARTERIES ARTERIES BODY TISSUES O2 out CO2 in LUNGS O2 in CO2 out HEART “pump” VEINS VEINS Gas exchange in lungs and tissues via capillaries.

The Heart ♥ - Structures Has 4 Chambers 2 chambers that receive blood from the body or the lungs back into the heart = atria (Right /Left Atrium) 2 chambers that receive blood from the atria and pump blood OUT of the body = ventricles (Right / Left ventricle)

4 Chambers of the Heart - Right Side The right side RECIEVES blood coming from the body and then pumps this blood out to the lungs 2 large vessels, called the vena cava, open into the Right Atrium The Superior Vena cava collects oxygen poor (CO2 rich) blood coming from tissues in the head, chest, and arms The Inferior Vena cava collects oxygen poor blood (CO2 rich) blood coming from tissues everywhere else in the body

4 Chambers of the Heart - Right Side The oxygen poor blood flows from the Right Atrium into the Right Ventricle, and then out into the pulmonary trunk From there, it enters into the left and right pulmonary arteries It then continues into the left and right Lungs for Gas Exchange

4 Chambers of the Heart - Right Side

4 Chambers of the Heart - Left Side It receives the OXYGEN RICH blood from the Left and Right Lungs and pumps this blood out into the body The Oxygen-rich blood flows from the lungs through the Pulmonary Veins to the Left Atrium The left atrium pumps blood into the left ventricle, where all the blood going to the body tissues leave through the LARGEST vessel in the body, the AORTA

Blood Carries out Functions Humans have approximately 5 Liters of blood moving continuously through the circulatory system Our blood is made up of: Plasma (55%) as well as Cells and cell fragments (45%)

Blood & its Components The blood plasma is made up of mostly water, with small amounts of proteins and other nutrients, oxygen, and carbon dioxide The cells and cell fragments make up for the solid parts of blood This consists of mainly red blood cells, some platelets, and some white blood cells

Understanding Blood Vessels There are 3 main types of blood vessels in the human body Arteries – carry blood AWAY from the heart Veins – carry blood TOWARDS the heart Capillaries – made up of cells that connect arteries and veins

Understanding Blood Vessels

Understanding Blood Vessels Artery Vein Capillary Very elastic walls that let the artery expand and contract based on stimuli The relaxation / contraction of artery walls helps make sure blood flows in the correct direction Have thinner walls and are not very elastic Do not contract themselves, but use the surrounding muscle’s contractions to keep blood moving in the correct direction Have One-Way VALVES that prevent blood from flowing backwards Smallest blood vessel found in networks within the body Join the arteries and veins together Where gases, nutrients, & other materials are transferred from blood to tissues / and tissue cells to blood

Checking for Understanding? Explain why someone going for a routine blood test would want to get blood taken out from a vein vs. an artery or capillary?

A Closer Look at the System The circulatory system is divided into 2 circular pathways Pulmonary circuit Systemic circuit

A Closer Look at the System The Pulmonary Circuit Works by moving blood from the heart to the lungs for gas exchange and back to the heart The blood carried from the heart to the lings is oxygen-poor (low in # of oxygen) Carbon dioxide in the blood then collects and moves to the lungs, where gas exchange happens, as CO2 moves out of the blood and fresh new Oxygen (from being breathed in through the lungs) enters into the blood This exchange of CO2 out and O2 in allows the blood to become enriched with oxygen, which then travels through the blood to the heart to be pumped throughout the body

A Closer Look at the System Systemic Circulation Works by moving blood from the heart to tissues everywhere in the body Blood carried from the heart to body tissues comes from the lungs, so its oxygen rich In the cells of the body tissues, oxygen in the blood is exchanged with carbon dioxide Where – the oxygen rich blood is pumped in the body, and oxygen poor blood returns to the heart to be pumped into the lungs for gas exchange to happen all over again

Diseases of the Circulatory System

Arteriosclerosis Is a general term that is used to describe several different conditions where the walls of the arteries thicken and lose their elastic properties, where they become harder The MOST common type of Arteriosclerosis is called Atherosclerosis Occurs when plaque (made of fatty deposits, cholesterol, calcium, and fibrous tissue) build up on the inside of the artery walls

Atherosclerosis https://www.youtube.com/watch?v=fLonh7ZesKs As the artery narrows because of the build-up, blood flow is decreased and blood pressure increases Plaque is VERY Dangerous if inside arteries that supply the heart, brain, legs, and kidneys Depending on WHERE plaque builds up, someone can experience Angina (Chest Pain), blood clots, shortness of breath, heart attack, or heart failure

Atherosclerosis More than 90% of heart attacks are due to Atherosclerosis A healthy lifestyle full of exercise, NOT smoking, eating a diet low in saturated fat and high in fruits and vegetables can help reduce the risk of developing this condition