Cardiovascular System

Which of these types of blood vessels carry blood away from the heart?

Artery

Which of these types of blood vessels carry blood back to the heart?

Vein

During a heartbeat, the atria relax as the _____ contract.

Ventricle

Blood Types

A person's blood is categorized into one of four groups, or types. The types include A, B, AB, and O. Blood type is an inherited trait. It is determined by what proteins are present on the surface of the red blood cells. •Type A blood contains the A protein. •Type B contains the B protein. •Type AB blood contains both proteins. •Type O blood contains neither protein. In addition to the four types, blood may be labeled as positive or negative for the Rh factor. The Rh factor is a type of substance that causes the body to produce antibodies. Rh-positive blood contains the factor, and Rh-negative blood does not.

Anemia

Anemia occurs when red blood cells do not supply enough oxygen to the body tissues. It results from a low amount of red blood cells or from a low amount of hemoglobin in the blood cells, or both. There are several types of anemia with different causes. Symptoms of any type of anemia include fatigue, shortness of breath, paleness, and rapid heart rate. Treatment varies depending on the type of anemia. It may involve dietary supplements, such as iron or vitamin B12, blood transfusions, or in severe cases, bone marrow transplant.

Blood

As the transporting fluid of the body, blood is vital to life. About 4-5 liters of blood circulate through the average body, accounting for about 8% of body weight. When spun in a special machine called a centrifuge, blood can be divided into solid and liquid parts. The solid parts are called formed elements, and the liquid part is the plasma.

Where does blood enter the heart?

Atria

Congestive Heart Failure

Congestive heart failure (CHF) occurs when the heart is unable to pump enough blood to supply the needs of the body. It may strike suddenly, or it may progress over a period of time. Symptoms include swelling, shortness of breath, fatigue, low blood pressure, and a rapid pulse. Treatment involves medication for the heart and to remove excess body fluids, elastic support hose, and oxygen therapy. In addition, rest and lifestyle changes are needed to relieve symptoms.

Heartbeat

Electrical impulses starting in the heart cause the muscles to contract and the heart to beat. Only the heart contains muscle tissue that can stimulate its own contractions. The right and left sides of the heart work together in a cycle to produce a heartbeat. First, the atria contract and push blood into the ventricles. The atria then relax, and as they are filling with blood, the ventricles contract and send blood to the parts of the body.

Arteries and veins both contain thick muscular tissue within their walls to pump blood throughout the body. True or False?

False

Like the heart, muscle tissue in the rest of the body can stimulate its own contractions with electrical impulses. True or False?

False

The solid parts of blood are called _______ _______.

Formed elements

How many chambers are in the heart?

Four

Heart Valves

Four valves in the heart keep the blood flowing in only one direction. •Atrioventricular valves are located between the atria and the ventricles on each side of the heart. These two valves include the tricuspid valve on the right side and the bicuspid valve, or mitral valve, on the left. •Semilunar valves are located between the ventricles and the vessels where blood leaves the heart. These two valves include the pulmonary valve and the aortic valve.

Hypertension

Hypertension is high blood pressure. This disease is often called the "silent killer" because it may not show any symptoms. If left untreated, it can lead to permanent damage to the heart, blood vessels, and kidneys. Risk factors that contribute to this condition are family history, race, obesity, smoking, stress, age, and a diet high in saturated fat. There is no cure. Treatment involves medication to control the blood pressure and to remove excess body fluids, reducing stress, avoiding tobacco, improving diet, and exercise.

Which side of the heart contains oxygenated, or oxygen-rich, blood?

Left

Leukemia

Leukemia is an abnormal increase in the number of white blood cells. The cells are immature and are not effective at fighting disease. They also take the place of red blood cells and reduce the amount of oxygen being carried to the body tissues. Symptoms include fatigue, anemia, bleeding gums, and excessive bruising. The condition can be life-threatening. Treatment involves radiation, chemotherapy, or bone marrow transplant. The patient may also be isolated to protect against infection.

Which layer of the heart is made of muscle tissue and pumps the blood through the system?

Myocardium

Which blood type is known as the universal donor?

O-

Blood Vessels

Outside of the heart, blood is carried throughout the body in blood vessels. The body contains three basic types of blood vessels. •Arteries carry blood away from the heart. •Veins carry blood back to the heart. •Capillaries are microscopic vessels that carry blood between the arterial and venous vessels. Arteries pump oxygenated blood out to the body with the help of their muscular, elastic tissue. The aorta, which pumps blood directly from the heart, is the body's largest artery. The aorta branches into other arteries, which then branch into smaller vessels called arterioles. The blood then moves to capillaries where gases, nutrients, and wastes are exchanged through the thin walls of the vessels. Tiny veins called venules receive the deoxygenated blood from the capillaries. Branches of venules come together to form larger veins. The blood is delivered to the heart by the body's two largest veins. The superior vena cava returns blood from the upper part of the body, and the inferior vena cava returns it from the lower part. Veins are thinner and much less muscular than arteries. Gravity and the movement of muscles around the veins help the blood continue to flow. Veins also have valves that keep blood from moving backward.

Which layer of the heart contains a lubricating fluid that reduces friction as the heart beats?

Pericardium

The pale yellow liquid that is left when formed elements are removed from blood is called _______.

Plasma

Plasma

Plasma is a pale yellow liquid that is left when formed elements are removed from blood. Whole blood is 55% plasma. Plasma is about 90% water and 10% proteins. It also has proteins that help fight infection and aid the clotting process. Serum is plasma without the clotting proteins. It may be used to research and identify antibodies.

Blood Transfusion

Prior to a blood transfusion, it is important for both the donor's and the recipient's blood to be tested for type and Rh factor. A person who receives blood from a donor with an incompatible type might have an adverse reaction. •Type O- has no substances that will cause antibodies to be produced. Therefore, it is known as the universal donor since it can be given safely to a person of any blood type. •Type AB+ blood is called the universal recipient because it can safely receive any other type of blood.

In what type of circulation does the blood flow between the heart and lungs?

Pulmonary

The Heart and its Layers

The heart is a two-sided, hollow organ about the size of a fist. It is located between the lungs in the thoracic cavity and behind the sternum, slightly to the left. The heart has three layers of tissue. •The pericardium is a double membrane, or sac, that covers the outside of the heart. It contains a lubricating fluid that reduces friction as the heart beats in order to prevent tissue damage. •The myocardium is the middle layer, and the thickest one. It is made of muscle tissue and pumps the blood through the system. •The endocardium is a smooth layer of cells that lines the inside of the heart and the blood vessels. It allows for the blood to flow smoothly through the system.

Sickle Cell Disease

Sickle cell disease occurs when the body produces abnormal red blood cells in the shape of a crescent. The cells cannot pass smoothly through the blood vessels, and they become clogged. As a result, the oxygen in the red blood cells does not get to the body's organs, which causes organ damage. The process of sickle cells stacking up within the blood vessels is extremely painful. The pain typically occurs in the chest, abdomen, bones or joints. An episode of severe pain is called a sickle cell crisis. Patients in crisis often require medical help to relieve the pain. Those affected by sickle cell disease have a weakened immune system. Other complications include vision problems, kidney damage, repeated strokes, anemia, and impotency. Treatment focuses on avoiding crises. Medications are available to reduce pain and complications. Blood transfusions, supplemental oxygen, and bone marrow transplant are all possible treatments, depending on the needs of the patient.

In what type of circulation does the blood flow between the heart and the cells of the body?

Systemic

Cardiovascular System

The cardiovascular system includes the heart, blood vessels, and blood. This system delivers oxygen and nutrients to cells throughout the body and carries waste away from them. As a result, it is often referred to as the "transportation system" of the body. The cardiovascular system performs these functions: •Supplies nutrients and oxygen to the body •Removes metabolic waste and carbon dioxide from cells •Distributes hormones and antibodies throughout the body •Helps control body temperature and electrolyte balance

Circulation of Blood

The flow of blood between the heart and the lungs is called pulmonary circulation. The right side of the heart pumps deoxygenated, or oxygen-poor, blood to the lungs. In the lungs, carbon dioxide is exchanged for oxygen. Then the oxygenated, or oxygen-rich, blood returns to the left side of the heart. The flow of blood between the heart and the cells of the body is called systemic circulation. The left side of the heart pumps the oxygenated blood to the rest of the body. The blood returns from the body to the right side of the heart to maintain continuous circulation.

Blood Cells

The formed elements of blood include red blood cells, white blood cells, and platelets. •Red blood cells, or erythrocytes, contain a protein called hemoglobin. Hemoglobin carries oxygen to all cells and removes carbon dioxide. Each red blood cell lives about 90-120 days. New cells are produced in the red marrow of bones in a process called hemopoiesis. The liver and spleen remove dead red blood cells and reuse the material. •White blood cells, or leukocytes, fight disease and infection. There are fewer white blood cells than red ones, and they are larger. Each white blood cells lives about 9 days. Pus consists of white blood cells mixed with bacteria. •Platelets, or thrombocytes, are the smallest blood cells. They help form clots to prevent blood loss from a wound. As they pass over a rough spot in a vessel, they become sticky. They may form a plug to seal small vessels by themselves or they may start the clotting process. Platelets are usually produced in red bone marrow and live for about 5-9 days.

Chambers of the Heart

The heart is separated into the right and left sides by a thick, muscular wall called the septum. Each side is divided into two parts to create four chambers in total. The top two chambers are called atria, and the bottom two are called ventricles. The blood enters the heart through the atria and leaves through the ventricles.

What is the purpose of the valves in the heart?

To keep the blood flowing in only one direction

A person's blood type is inherited. True or False?

True

Path of Blood through the Heart

When deoxygenated blood returns from the body, it follows this path through the heart. 1.The right atrium receives deoxygenated blood from the body through the inferior and superior vena cava. 2.The blood moves to the lower portion of the heart through the tricuspid valve. The valve prevents blood from moving back into the right atrium. 3.The right ventricle fills with blood. 4.The right ventricle contracts to send the blood through the pulmonary valve to the pulmonary artery and the lungs. The valve prevents blood from returning to the right ventricle. 5.The left atrium receives oxygenated blood from the lungs through the pulmonary veins. 6.The blood moves to the lower portion of the heart through the bicuspid (mitral) valve. The valve prevents blood from moving back into the left atrium. 7.The left ventricle fills with blood. 8.The blood leaves the heart through the aortic valve to the aorta, which sends the blood to all parts of the body. The valve prevents blood from returning to the left ventricle.