9 th Health Southland Academy Chapter 16 Cardiovascular and Respiratory Systems

The Cardiovascular System The cardiovascular system consists of vessels that transports life-supporting materials to the cells of your body. Your heart, one of the main organs of the circulatory system, is the central point form which these vessels branch from.

Functions of the Cardiovascular System The cardiovascular system is composed of the heart and all the blood vessels of the body. The function of the cardiovascular system is to circulate blood (nourishes the cells of your body). As your heart pumps blood, blood cells pass through the vessels carrying oxygen (O 2 ) and nutrients to the cells. At the same time, carbon dioxide (CO 2 ) along with waste materials are carried away from the cells.

Structure of the Cardiovascular System The cardiovascular system consists of: 1. Heart 2. Blood 3. Blood Vessels (arteries, veins, capillaries)

The Heart The heart and brain are 2 of the most important organs in the human body. The heart is the pump that makes the cardiovascular system work. Most of the heart is made of cardiac muscle tissue called myocardium. The myocardium is responsible for the contracting and relaxing of the heart that is the heartbeat. Your heart rates adjusts automatically to physical activity. Average lifespan  2.5 billion heartbeats

Chambers of the Heart The human heart has 4 chambers. The upper, small chambers of the heart  atrium ( atria – plural) The lower, larger chambers of the heart  ventricle ( ventricles – plural ) Septum  wall of tissue that separates the left and right chambers of each atria and ventricles. The heart has an area of muscle in the right atrium that acts as the natural pacemaker.

Chambers of the Heart Valves between the atria and ventricles allow blood to flow through the chambers of the heart. These valves are “one-way” valves opening only to allow blood to flow from the atria into the ventricles.

Path of a Blood Cell Through the Heart Pathway of blood through the heart Blood enters the right atrium from the superior and inferior venae cavae. From right atrium, it goes through the tri cuspid valve to the right ventricle. From the right ventricle, it goes through the pulmonary artery (to lungs) While the blood is in the lung, it picks up oxygen (O 2 ) From the lungs, oxygenated blood is returned to the heart through the pulmonary veins. From the pulmonary veins, blood flows into the left atrium. From the left atrium, blood flows through the bi cuspid valve into the left ventricle. From the left ventricle, it goes through the ascending aorta then to descending aorta. Blood is distributed to the rest of the body (systemic circulation) from the aorta.  Widowmaker – massive leak/breakage of the ascending aorta  

The Heart

Blood Cells Blood delivers oxygen, hormones and nutrients to cells. Blood also carries away wastes away from cells. 55% of blood is plasma Plasma – fluid in which other parts of the blood (RBC’s, WBC’s, etc.) are suspended. Plasma is mostly water. Red blood cells make up 40% of blood. White blood cells make up 5% of blood.

Red Blood Cells Red blood cells transport O 2 to cells. RBC’s are formed in bone marrow. RBC’s contain hemoglobin – oxygen carrying protein in RBC’s. Hemoglobin contains iron that binds with oxygen in the lungs and releases the oxygen in the tissues.

White Blood Cells The main role of white blood cells is to protect the body from infection and to fight infection when it occurs. WBC’s are a part of the body’s immune system and are produced in the bone marrow. Production of WBC’s increase when an infection is present. One form of Leukemia is when the body produces too many WBC’s

Platelets Platelets – cells that prevent loss of blood. Platelets gather at the site of an injury and release chemicals. These chemicals makes them sticky and clump together. Fibrinogen is produced which produces a “net-like” structure that traps the clumps. These clumps will then clot and stop the bleeding.

Blood Vessels The body contains more than 60,000 miles of blood vessels. There are 3 types of blood vessels: 1.Arteries 2.Veins 3.Capillaries

Arteries Arteries  carries blood away from the heart. Arteries have thick, elastic walls made of smooth muscle. The elastic fibers allows the walls of the arteries to withstand the pressure as the heart beats. As arteries move away from the heart, they branch into smaller vessels  arterioles. Arterioles deliver blood to capillaries. Aorta  largest artery of the body, first artery leading from the heart to the rest of the body.

Veins Veins – carry blood back to the heart. Walls of veins are thinner than arteries. Walls of veins are less elastic. Vena Cava  Deoxygenated blood returns to the heart (right atrium) from the rest of the body. Superior Vena Cava  blood returns from upper half of the body. Inferior Vena Cava  blood returns from the lower half of the body. Veins contain valves to “push” blood along back to the heart.

Capillaries Capillaries – Connect arteries (arterioles) to veins (venules). Capillaries is where O 2 is exchanged into cells through diffusion (movement from an area of high concentration to low concentration). Capillaries is where CO 2 is picked up by red blood cells and returned to the heart for exhaling. Capillaries also play a role in temperature regulation.

The Heart

The Lymphatic System The lymphatic system also helps fight infection and plays and important role in the body’s immunity to disease. Lymph – the clear fluid that fills the spaces around cells. Lymph is similar to plasma in content, consisting of water and proteins. Lymphocytes – specialized white blood cells that provide the body with immunity.

Health Behaviors and the Cardiovascular and Lymphatic Systems Healthful habits can help reduce many of the risk factors associated with problems of the cardiovascular and lymphatic systems.

Health Behaviors and the Cardiovascular and Lymphatic Systems HEALTHFUL BEHAVIORS FOR CARDIOVASCULAR AND LYMPHATIC SYSTEMS: 1.Follow a well-balanced diet that is low in saturated fats, cholesterol and salt. 2.Maintain a healthy weight to reduce stress on the heart, blood vessels and lymph vessels. 3.Participate in regular aerobic exercise for minimum 30 minutes for 3 or 4 times a week. 4.Avoid the use of tobacco products and exposure to second hand smoke. 5.Avoid illegal drugs.

Blood Pressure Maintaining proper pressure in the cardiovascular system is important for proper blood circulation. Pressure in arteries is created as ventricles contract. Blood Pressure – the measure of the amount of force that blood places on the walls of blood vessels as it is pumped throughout the body. Sphygmomanometer – instrument used to check blood pressure.

Blood Pressure Systolic pressure – the maximum pressure, the number on top. Diastolic pressure – the minimum pressure, the number on the bottom. Good blood pressure 120/80 Blood pressure is an indicator of cardiovascular health.

High Blood Pressure Risk Factors Anyone can develop high blood pressure, but you are more at risk if you : Are over 45 years old Are overweight Have family member with high blood pressure Eat a diet high in salt Drink too much alcohol Smoke

High Blood Pressure Risk Factors While you can’t change some of these risk factors, you can change others. For example, you can’t change your age, but you can limit how much salt you eat. These kinds of healthy changes can help you prevent or control high blood pressure and protect your kidneys.

Cardiovascular System Problems Disorders of the cardiovascular system can : 1.Interfere with blood flow through the heart or body 2.Reduce the amount of oxygen that reaches cells 3.Keep blood from clotting properly Some problems are inherited and some are the results of illness or disease.

Congenital Heart Defects Congenital – a condition that is present at birth. Common congenital heart defect is the septum defect – hole in the septum allows unoxygenated and oxygenated blood to mix. Some congenital heart defects are less serious than others, but most require a minimum of medication and possibly even surgery.

Cardiovascular Diseases Cardiovascular disease is actually a group of diseases: 1. Hypertension (high blood pressure) 2. Heart disease 3. Heart attack 4. Stroke CVD is the #1 killer of men and women. Many of these diseases are associated with lifestyle behaviors (smoking, alcohol, drug, high-fat diets) Early detection is important!

Heart Murmur Heart murmur – abnormal sound that is made as the blood flows through the heart. Most are slight and disappear without treatment. Some may indicate a real problem with the heart and it’s function  valve b/w left atrium and ventricle not closing properly.

Anemia Anemia – condition in which the ability of the blood to carry oxygen is reduced. Causes  low red blood cell count, low hemoglobin Most common cause of anemia  iron deficiency. To prevent anemia  eat green, leafy vegetables, red meat, egg yolks

Leukemia Leukemia – form of cancer in which white blood cells are produced excessively and abnormally. Chemotherapy and radiation are among treatment options. Childhood leukemia is often curable and in adults can go into remission.

Hemophelia Hemophelia – inherited disease in which the blood does not clot properly. Clotting factors, normally found in blood, in missing. This may cause uncontrollable bleeding.

The Respiratory System Breathing is regulated by certain areas of the brain that send impulses that stimulate the muscles involved in respiration to contract automatically.

Functions of the Respiratory System The main function of the respiratory system is respiration. Respiration – the exchange of gases (O 2 & CO 2 ) in the body. 2 Types of Respiration 1. External Respiration – the exchange of O 2 and CO 2 that takes place between air and blood in the lungs. 2. Internal Respiration – the exchange of gases between blood and body cells.

Structure of the Respiratory System LUNGS The lungs are the main organs of the respiratory system. The lungs are found inside the chest and protected by the ribs. Diaphragm – muscle that separates the chest from the abdominal cavity. The contraction and relaxation of the diaphragm forces air into the lungs due to pressure.

Structure of the Respiratory System Epiglottis – flap of tissue that closes over the trachea when you swallow. Larynx – the voice box, contains vocal cords. Bronchi – passages in which air spread out in the lungs. Alveoli – tiny air sacs inside the lungs, where external respiration occurs (exchange of O 2 & CO 2 ). Capillary – connects arteries and veins inside the lungs, specifically where external respiration occurs.

Structure of the Respiratory System

Care and Problems of the Respiratory System Many respiratory system disorders can be prevented by practicing positive health habits. The single most important for good respiratory health is TO NOT SMOKE! Smoking damages the respiratory system and is the main cause of lung cancer.

Care and Problems of the Respiratory System Bronchitis – inflammation of the bronchi caused by infection or exposure to tobacco smoke or pollution. Pneumonia – inflammation of the lungs caused by bacterial or viral infection. Pleurisy – inflammation of the lining of the lungs and chest cavity. Asthma – inflammation in which trachea, bronchi and bronchioles becoming narrowed, causing difficulty in breathing. Emphysema – disease that progressively destroys the walls of the alveoli.