9th HealthSouthland Academy

Chapter 16Cardiovascular 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 (O2 ) and nutrients to the cells.

• At the same time, carbon dioxide (CO2 ) along with waste materials are carried away from the cells.

Structure of the Cardiovascular System

• The cardiovascular system consists of:1. Heart2. Blood3. 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 tricuspid 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 (O2)

• 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 bicuspid 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 https://www.youtube.com/watch?v=BEWjOCVEN7M https://www.youtube.com/watch?v=7XaftdE_h60

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 O2 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. Arteries2. Veins3. 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 O2 is exchanged into cells through diffusion (movement from an area of high concentration to low concentration).

• Capillaries is where CO2 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

body2. Reduce the amount of oxygen that reaches cells3. 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 attack4. 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 (O2 & CO2) in the body.

• 2 Types of Respiration• 1. External Respiration – the exchange of O2 and CO2

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 O2 & CO2).

• Capillary – connects arteries and veins inside the lungs, specifically where external respiration occurs.

Structure of the Respiratory System

Structure of the Respiratory System

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.