The Body s Transport System

Transcription

1 The Body s Transport System When you hear the word heart, what do you think of first? Many people think of romance. Some people think of courage. But the heart is much more than a symbol of love or bravery. Your heart is an amazing pump.

2 The Cardiovascular System What is another name for the system? Cardiovascular or Circulatory What is the function of the system? Carries needed substances to cells, carries waste products away from cells. Blood contains cells that fight diseases.

3 The Cardiovascular System What are the substances transported? Oxygen (O2) Waste (CO2) Nutrients Glucose Disease fighting cell White Blood Cells

4 The Cardiovascular System Delivering Needed Materials - Most substances that need to get from one part of the body to another are carried by blood. For example, blood carries oxygen from your lungs to your other body cells. Blood also transports the glucose your cells use to produce energy. Removing Waste Products The cardiovascular system picks up wastes from cells. For example, when cells break down glucose, they produce carbon dioxide as a waste product. The carbon dioxide passes from the cells into the blood. The cardiovascular system then carries carbon dioxide to the lungs, where it is exhaled. Fighting Disease The cardiovascular system also transports cells that attack disease-causing microorganisms. This process can help keep you from becoming sick. If you do get sick, these disease-fighting blood cells will kill the microorganisms and help you get well.

5 The cardiovascular system consists of the heart and the three types of blood vessels that carry blood throughout your body.

6 The Heart Hollow muscular organ that pumps blood through the body (Two Pump organ) Size of fist Located center of the body, behind the sternum (breast bone) Each beat pushes blood through the blood vessels Composed of cardiac muscle tissue

7 The Heart Structure Has a right and left side Right side is separated by a wall of tissue called the septum Each side has two chambers, and upper and lower chamber The upper chambers are called atrium (AY tree um) and both receive blood to the heart. Lower chambers are called the ventricles and pump blood out of the heart. A valve between chambers (atrium & ventricles) prevents blood from flowing backwards

8 How the Heart Works Two main phases for the action of the heart. Phase one: muscle relaxes and heart fills with blood Phase two: the heart muscle contracts and pumps blood forward. Heart beat, lup-dup, is what is heard during the pumping phase.

9 Flow of Blood Through the Heart

10 How the Heart Works When the heart muscle relaxes, blood flows into the chambers. The atria contact and the muscle contraction squeezes blood out of the atria, through the valves into the ventricles. Next, the ventricles contraction closes the valves between the atria and ventricles, making the lub sound and squeezing blood into large blood vessels. As the valves between the ventricles and the blood vessels snap shut, they make the dup sound.

11 Patterns of Blood Flow

12 Two Loops What happens in the two loops? First, the blood travels through three kinds of vessels Arteries, capillaries, and veins. Arteries - carry blood away from the heart and it flows into tiny narrow vessels called capillaries. In capillaries the blood and the cells exchange materials. From capillaries, blood flows into veins that carry blood back to the heart.

13 Two Loops Loop One: Blood travels from the heart to the lungs Blood flows into the right atrium Then to the right ventricle and out to the lungs via the pulmonary artery Blood in the lungs exchange oxygen and carbon dioxide

14 Two Loops Loop One: To the Lungs and Back When blood from the body flows into the right atrium, it contains little oxygen but a lot of carbon dioxide. This oxygen-poor blood is dark red. The blood then flows from the right atrium into the right ventricle. Then, the ventricle pumps the oxygen-poor blood into the arteries that lead to the lungs.

15 Two Loops Loop One: To the Lungs and Back As blood flows through the lungs, large blood vessels branch into smaller ones. Eventually, blood flows through tiny capillaries that are in close contact with the air that comes into the lungs. The air in the lungs has more oxygen than the blood in the capillaries. Therefore, oxygen moves from the lungs into the blood. For the same reason, carbon dioxide moves in the opposite direction from the blood into the lungs. As the blood leaves the lungs, it is now rich in oxygen and contains little carbon dioxide. This blood, which is bright red, flows to the left side of the heart and will be pumped through the second loop.

16 Two Loops Loop Two: Blood returns from the lungs into the left atrium Blood leaves the heart via the left ventricle and travels throughout the body Oxygen moves out of the blood into the body cells and takes up carbon dioxide. Blood returns to the heart and loop one starts again.

17 Two Loops Loop Two: To the Body and Back The second loop begins as the left atrium fills with oxygen-rich blood coming from the lungs. The blood then moves into the left ventricle. From the left ventricle, the blood is pumped into the aorta (ay AWR tuh), the largest artery in the body. Eventually, after passing through branching arteries, blood flows through tiny capillaries in different parts of your body, such as your brain, liver, and legs. These vessels are in close contact with body cells. Oxygen moves out of the blood and into the body cells. At the same time, carbon dioxide passes from the body cells into the blood. This blood, which is low in oxygen, then flows back to the right atrium of the heart through veins, completing the second loop.

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25 How the heart actually pumps blood Heart Lab

26 The Force of Ventricles When the muscle cells in the ventricles contract, they exert a force on the blood. The force pushes the blood out the heart and into the arteries. Contraction of the right ventricle sends blood to the lungs. Contraction of the left ventricle sends blood throughout the rest of the body

27 The Force of Ventricles Open and Closed Heart Valves As blood flows out of the heart and toward the lungs, it passes through a valve like the one in the photographs on the right.

28 Regulation of the Heartbeat How does the heart know A group of heart cells how fast to beat? called the pacemaker sends out signals that make the heart muscle contract and adjusts how fast it beats based on oxygen levels.

29 Regulation of the Heartbeat What happens if the pacemaker is damaged? If damaged as a result of disease or an accident. It may result in an irregular or slow heartbeat. However, in the 1950s, doctors and engineers developed an artificial, battery-operated pacemaker. Modern artificial pacemakers are implanted beneath the skin and are connected by wires to the heart. Tiny electrical impulses travel from the battery through the wires, and make the heart contract.

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35 Regulation of the Heartbeat Heart Rate Lab

36 A Closer Look at Blood Vessels How long are the Blood Vessels in your body? If you were to line them all up then it would be 100,000 kilometers. The blood vessels throughout your body transport the vital liquid to your survival blood.

37 Arteries Where does blood go after it leaves the heart? It travels through arteries. The right ventricle pumps blood into the arteries that go to the lungs. The left ventricle pumps blood into the aorta. Smaller arteries branch off the aorta. The blood at this point is deoxygenated.

38 Arteries Where does the branches go from the aorta? The first branches are coronary arteries which carry blood to the heart itself. Other branches go to the brain, intestines, and other organs. Each artery branches into smaller and smaller arteries.

39 Arteries How are arteries put together? They have thick walls with three layers. 1.The innermost layer is smooth epithelial cells. This allows blood to flow freely. 2.A middle layer is smooth muscle tissue. 3.An outer layer of flexible connective tissue. Arteries are strong and flexible to handle pressure.

40 Arteries What causes your pulse? The alternating expansion and relaxation of the artery wall every time your heart beats. Rhythmic change in blood pressure. The ventricle contracts and sends a spurt of blood out through the arteries and it pushes the walls causes them to expand. After spurt passes, the walls relax and narrow again. Average rate is beats per minute.

41 Arteries How is blood flow regulated? The muscle as as a control gate. Muscles contract making the opening in the artery smaller, allowing less blood to flow, or they can relax and make the opening larger, allowing more blood to flow.

42 Capillaries What do capillaries do? After the blood flows from the smaller arteries. They flow into capillaries where materials between your cells and blood exchange. Capillaries are only one cell thick to allowing materials to pass through easily. Materials like oxygen and glucose pass from the blood, through the capillary walls, to the cells. Waste goes from cells to capillaries then blood.

43 Veins Where does blood go after it leaves the capillaries? It enters larger blood vessels called veins, which carry blood back to the heart.

44 Veins How are veins structured? Veins are structured just like arteries, except their layers are thinner than arteries. Generally blood flows much slower through veins because the blood is so much further from the heart. To make sure the blood does get back your skeletal muscles help push the blood along, as well as having valves in many of your veins.

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46 Cardiovascular Problems What causes cardiovascular problems? They can be caused by smoking, high levels of cholesterol in the blood, stress, physical inactivity, or heredity. Eating a healthy diet and getting plenty of exercise can reduce the risk of having cardiovascular problems.

47 Cardiovascular Problems What are the diseases of the cardiovascular system? Atherosclerosis (ath uh roh skluh ROH sis) Hypertension (hy pur TEN shun)

48 Atherosclerosis What is atherosclerosis? Atherosclerosis is a condition in which an artery wall thickens as a result of the buildup of fatty materials. Cholesterol is one of the materials and it is a waxy substance. Atherosclerosis reduces the flow of blood in the affected artery.

49 Atherosclerosis Where can atherosclerosis develop? It can develop in the coronary arteries, which supply blood to the heart. What happens when there is It can lead to a condition less blood and oxygen? called a heart attack.

50 Atherosclerosis When does a heart attack occur? It happens when blood flow to part of the heart muscle is blocked. What happens in the heart? The cells in the heart die on that part that did not receive enough blood and oxygen. Damage is permanent.

51 Atherosclerosis Are there treatments for atherosclerosis? Mild atherosclerosis can be treated with a low fat diet and exercise program. Medication can also be used to lower cholesterol. Severe atherosclerosis can be treated with surgery to unclog blocked arteries.

52 Atherosclerosis What happens if not treated? Heart Failure which happens if too many cells die and the heart becomes so damaged, that it can't pump enough blood to meet the body's needs. Organs become damaged due to lack of oxygen or nutrients, or to waste buildup in the body.

53 Hypertension What is hypertension? It is a disorder in which a person s blood pressure is consistently higher than normal 140/90. It makes the heart work harder to pump blood through the body. It damages the walls of blood vessels. It can cause harm to the arteries.

54 Hypertension What is a risk of having hypertension? A stroke is when a blood vessel in the brain becomes clogged or ruptures. As a result, that part of the brain receives no oxygen. Without oxygen, brain cells die.

55 Hypertension Are there any warning signs? It has no obvious symptoms to warn people until it is severe. This is why it is often called the silent killer.

56 Hypertension How can it be treated? Mild hypertension, regular exercise and careful food choices may be enough lower blood pressure. Limit sodium intake by avoiding processed foods like snacks and soups. However, medication is also needed in some cases to reduce their blood pressure.

57 Keeping Healthy What can people do for a healthy cardiovascular system? Be aware that as early as young as years old, some signs of atherosclerosis have been found. To help maintain cardiovascular health, people should exercise regularly; eat a balanced diet low in sodium, cholesterol, saturated and trans fats. Finally, avoid smoking and second had smoke.

58 Keeping Healthy What can people do for a healthy cardiovascular system? Finally, avoid smoking and second had smoke. It makes the heart beat harder and faster. It also increases the amount of carbon monoxide in the blood (a poison).

59 Blood Blood is part of the circulatory system. It travels through miles and miles of blood vessels to reach every cell in your body. So, you must have a lot of blood, right? Well, actually, an adult human body has about 5 L of blood. Your body probably has a little less than that. All the blood in your body would not fill two 3 L soda bottles.

60 Blood Is blood just a plain red liquid? NO!!!!! It is actually a complex tissue that has several parts. It makes up about 7% - 8% of the body s total mass. What are the parts of blood? Blood is a connective tissue made up of four components: plasma, red blood cells, platelets, and white blood cells. Only 45% is cells with the remainder consisting of plasma.

61 Blood What is the function of blood? carries oxygen from lungs to body cells and carries carbon dioxide from body cells to lungs to be exhaled carries waste products from cells to kidneys transports nutrients and other substances to body cells cells and molecules in blood fight infections and help heal wounds

62 Plasma What is plasma? The liquid part of your blood, which is 90% water. Plasma (PLAZ muh) also carries nutrients, such as glucose, fats, minerals, proteins, and other things like hormones and cholesterol. It also carries chemical messages that direct activities in the body like the uptake of glucose by the cells. It carries away waste produced by cells.

63 Plasma What is makes it look yellow? Proteins molecules make it appear yellow. There are three groups of plasma proteins. What is the function of the proteins in plasma? Group one regulates the amount of water in blood. Group two produces white blood cells to fight disease. Group three interacts with platelets to form blood clots.

64 Red Blood Cells - Erythrocytes What is the purpose of red blood cells? Where are they made and what do they look like? Without them, your body could not use the oxygen that you breathe. Red Blood Cells (RBC) take up oxygen in the lungs and deliver it to cells in the body. Red blood cells are produce by bone marrow. They appear like disks due to their pinched shape. (thin in the middle and can bend and twist)

65 Red Blood Cells What is the composition of red blood cells? Red blood cells make up 40 45% of the blood. They contain hemoglobin (Hee muh gloh bin), which carries the oxygen needed by the body. Each molecule has four iron atoms, which bind to a molecule of oxygen and become bright red. In the capillaries, the hemoglobin drops off the oxygen for the cells to use. Iron gives blood its red color.

66 Red Blood Cells Why does blood turn dark red? Without oxygen, the cells are dark red. Therefore, blood leaving the aorta is bright red from the heart and returning blood through veins to the heart are dark red.

67 Red Blood Cells What does hemoglobin do for you? It picks up oxygen in the lungs and releases it as blood travels through capillaries in the rest of the body. It also picks up some of the carbon dioxide produced by cells. However, most of the carbon dioxide is carried by plasma. The blood carries the carbon dioxide to the lungs, where it is released from the body.

68 Red Blood Cells Can red blood cells reproduce? They cannot reproduce or repair themselves because they have no nuclei. Without a nucleus, mature red blood cells only live about 120 days. About 2 million red blood cells in your body die every second. However, your bone marrow produces new red blood cells at the same rate. Cancelling out what was lost without you knowing.

69 Platelets What are platelets? (PLAYT lits) They are cell fragments from the bone marrow that play a major role in forming blood clots. They do not have a nuclei and only last 5 to 10 days. They release chemicals that start a chain reaction. It produces a protein called fibrin (FY brin). The fibrin weaves a net of tiny fibers across the cut in blood vessels.

70 Platelets How do blood clots form? The weaved net that was created by the fibrin traps more platelets and blood cells causing them to form a blood clot. Weaves a net of tiny fibers across the cut in blood vessels. A scab is a dried blot clot on the skin s surface.

71 White Blood Cells - Leukocytes What is the purpose of white blood cells? They are the body s disease fighters. White Blood Cells (WBC) recognize disease-causing organisms called pathogens (PATH uh juhnz). Some cells fight infections and "invasions" by viruses and bacteria. Other cells "eat" or destroy bacteria, parasites, and even dead, damaged or old body cells. They also help clean wounds.

72 White Blood Cells - Leukocytes What is the purpose of white blood cells? WBCs release antibodies. Antibodies are chemicals that identify or destroy pathogens. WBCs also keep you healthy by destroying body cells that have died or been damaged. Some WBCs mature in the lymphatic system.

73 White Blood Cells

74 White Blood Cells Where are they made and how are different from red blood cells? White blood cells are also produce by bone marrow. Unlike red blood cells, the marrow only produces fewer. If compared for every white blood cell there is about 500 to 1,000 red blood cells. They are larger than red blood cells, have a nuclei which allows them to live for months to years.

75 White Blood Cells What do the different white cells look like and what are they called?

76 Red Blood Cells (RBC) Oxygen is carried by red blood cells. The body has more red cells than any other kind of cell. White Blood Cells (WBC) Finds and destroys disease-causing organisms, white blood cells fights disease. Platelets Helps forms blood clots that stops bleeding. Aren t whole cells, but pieces of cells with no nuclei.

77 Other Blood Facts With each heart beat, about 70 ml of blood (about 1/3 of a cup, or a little less than 5 tablespoons) is pumped out of the heart. The average adult male has a little more than 5 quarts (about 5 liters). Women and children have less. A child has over 60,000 miles of blood vessels, while an adult has close to 100,000 miles of blood vessels. Blood cells are made in the bone marrow. In children, the marrow in most bones makes blood. In adults, only the marrow of certain bones, like the spine, ribs, pelvis, and a few others still makes blood. The marrow of the rest of the bones turns into yellow marrow, which stores fat.

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84 Blood Composition Lab

85 Body Temperature Regulation What else does your blood do? It also helps regulate your body temperature. When your brain senses the temperature is rising, it signals blood vessels in your skin to enlarge. As the vessels enlarge, heat from your blood is transferred to your skin. This transfer helps lower your temperature. When your brain senses that your temperature is normal, it instructs your blood vessels to return to their normal size.

86 Blood Pressure What is Blood pressure? Blood pressure is a measure of how strong your blood is pushing against the sides of your blood vessels. It is the force with which the ventricles contract. Blood moves away from the heart, pressures decreases and blood near the heart arteries exerts the higher pressure. BP in arteries farther from heart is much lower.

87 Blood Pressure How do you measure blood pressure? A sphygmomanometer (sfig moh muh NAHM uh tur ). A cuff is wrapped around the upper arm. Air is pumped into the cuff until the blood flow through the artery is stopped. As the pressure is released, the examiner listens to the pulse and records two numbers measures blood pressure with two numbers, such as 110/70 mm Hg

88 Blood Pressure How do you measure blood pressure? Blood pressure is expressed in millimeters of mercury. The first number is the systolic (sis TAHL ik) pressure when the heart ventricles contracts. The second is the diastolic (DIE uh STAHL ik) pressure when the heart ventricles relaxes. The numbers are expressed as a fraction: Contraction Relaxation

89 Normal Blood Pressure For adults, a blood pressure of 120/80 mm Hg or below is considered healthy. High blood pressure can cause heart or kidney damage.

90 Blood Types What are the four blood types? The four types are A, B, AB and O. Your blood type refers to the chemicals you have on the surface of your RBCs. These chemicals are called antigens (AN tuh juhnz). If your blood is type A, you have the A antigen. If your blood is type B, you have the B antigen. If your blood is type AB, you have both A and B antigens. If your blood is type O, you DO NOT have A or B antigens.

91 Blood Types The different blood types have different antigens on their RBCs. They may also have different antibodies in the plasma. These antibodies react to antigens of other blood types as if the antigens were pathogens. (See chart on right) Type A blood has antibodies that react to type B blood. If a person with type A blood receives type B blood, the type B antibodies attach themselves to the type B RBCs. These RBCs begin to clump together, and the clumps may block blood vessels. A reaction to the wrong blood type may be fatal.

92 Blood Types When would you need a blood transfusion? When a person loses a lot of blood. A blood transfusion is the transfer of blood or blood components from person to another to replace lost due to injury or surgery. Early attempts failed but no one knew why until the early 1900s when Karl Landsteiner tried mixing various types with different results.

93 Blood Types What did Landsteiner discover? Landsteiner found that some pairs would blend smoothly and others would clump together, Clumping caused failed transfusion and lead to death. Landsteiner went on to discover that there are four major blood types and they are determined by proteins known as marker molecules.

94 Blood Types What happens if you mix the wrong markers? If blood with the wrong marker is present your body releases clumping proteins that clump the foreign blood together. For example if your blood is type A, your blood contains clumping proteins that act against cells with B markers. So, if you receive a transfusion of type B blood, your clumping proteins will make the foreign type B cells clump together.

95 Blood Types What did Landsteiner s work led to for transfusions? Safer transfusions by knowing the marker molecules on your red blood cells and how they determine your blood type and type of blood you can receive in transfusions. What blood types are compatible? Type A can get A or O. Type B can get B or O Type AB can get A, B, AB, and O because it has no clumping proteins. Type O can get O.

96 Blood Types

97 Blood Types How do you check before a transfusion? Have your blood checked first. Then, donate blood that you can safely receive will be found. This process is called cross matching. You may have heard a Dr. on a TV show say let s type and cross. Basically, he asking what is the patients blood type and if a cross match was done on the donated blood.

98 Blood Type Distribution The chart on the right shows the percentage of each blood type in the United States. Note: Different percentages based on ethnic groups.

99 Your Blood Type The chart on the right shows possible types based on parents blood type

100 Rh Factor What else did Landsteiner discover? He discovered the presence of another protein on red blood cells, which he called Rh Factor. He found that 85% had the marker and 15% did not. Like the blood types, the Rh factor is determined by a marker on the red blood cell.

101 Rh Factor What does it mean to have (+) or (-) attached to your blood type? People with Rh positive have the Rh marker. People with Rh negative do not have the marker on your red blood cells. Can Rh+ receive Rh- blood? You can only receive blood with the same markers or you would develop Rh clumping proteins in your plasma. Which is a dangerous situation.

102 Blood Disorder What is leukemia? When one type of white blood cells is made in excess and cannot fight infections, they crowd out healthy cells, lower red blood cell count, normal white blood cell and platelet count. This can affect children, but more common in adults. Treated by medicine, blood transfusions, and bone marrow transplants.

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106 Blood Type Lab