Presentation on theme: "Chapter 38 Circulatory and Respiratory Systems. The Circulatory System Transport and distribution -Cardiovascular system: connects all the muscles and."— Presentation transcript:
Chapter 38 Circulatory and Respiratory Systems
The Circulatory System Transport and distribution -Cardiovascular system: connects all the muscles and organs of the body. -Driven by the heart -Kinds of molecules it moves: -Nutrients from digested food -Oxygen from lungs -Metabolic wastes IE carbon dioxide -Hormones: substance that help coordinate activities of the body -Distributes heat.
Blood vessels -arteries: vessels that carry blood away from the heart, oxygen rich (we typically think of them as being red) -Walls have three layers of tissue -Endothelium (innermost) single layer of cells -Smooth muscle surrounds it (elastic fibers) -Protective connective tissue, also elastic, on the outer most. -Capillaries: is where we exchange gases, nutrients, hormones, and other molecules with each cell. -No cell in your body is more than a few cell diameters away from a capillary -Walls are only 1 cell thick -Also very narrow
-Veins: carry blood towards the heart. (we typically think of them as being blue) -Walls of veins are much thinner than arteries -Low pressure (arteries are very high pressure) -No pulsing pressure (arteries do) -Typically larger in diameter than arteries -Have one way valves (flap of tissue to prevent back flow) -Varicose veins: weak and dilated, allow some back flow. -Dilated veins in the anal area are called hemorrhoids.
Lymphatic system -Collects and recycles fluids leaked from the cardiovascular system and is involved in fighting infections. -Made up of a network of vessels called lymphatic vessels and bean-shaped structures called lymph nodes. -Lymph: leaked fluid -Lymph nodes in various parts of the body sometimes get tender or swell, typically when fighting an infection of some kind.
The Blood!!! Components of blood -plasma: the liquid portion of blood, 90% water, 10% solutes (found below) -Metabolites and waste -Salts (ions) mainly sodium, chloride, and bicarbonate important in maintaining osmotic balance and regulating pH. -Proteins: most abundant of the solutes, help with clotting, balance, and even antibodies.
The rest of the blood (about 40%) is made up of three parts, red and white blood cells and platelets. Red blood cells (RBC) -Make up most of this -Cells that carry oxygen (and there are a bunch of them) -Also called erythrocytes -Packed with hemoglobin (an iron containing protein that binds oxygen in the lungs) -Mature RBC’s do not have a nucleus, therefore can not repair themselves -Biconcave shape -Short life span (about 4 months) -Constantly being produced by stem cells and specialized cells in bone marrow. -Anemia: oxygen carrying ability is reduced
White Blood Cells (WBC) -Primary job is to defend the body against disease. -Larger than RBC’s -Many different types (each with different immune function) -Some destroy, some produce antibodies (proteins that mark foreign substances for destruction)
Platelets -Pinched off bits of cytoplasm from large cells in bone marrow -Play an important role in blood clotting -When a hole develops, blood loss must be stopped -Platelets arrive at location, change shape, get larger, and release a substance that makes them very sticky. -This eventually forms a sticky lump that plugs the hole -Larger wounds: platelets releasing a clotting enzyme that activates a series of chemical reactions forming fibrin. -Fibrin threads a net trapping RBC’s and platelets which will then plug the hole. -Lack of this ability is known as hemophilia.
Blood Types!! -Blood type is determined by the presence or absence of a specific carbohydrate on the surface of the RBC. ABO blood group system. -Four types of blood: A, B, AB and O. -A and B means that there is the presence of a carb. And it acts as an antigen (antigens cause your body to produce anti-bodies, provokes an immune response). -AB has both the A and B antigen -O has neither of these. -Know the chart on page 879 Table 1: blood types.
-AB blood is the universal recipients -O blood is the universal donors. Rh Factor -This is another important antigen on the surface of RBC’s -Present they are Rh+ -Absent they are Rh- -Rh- mother will generate anti-bodies which would attack a fetus with Rh+, and destroy it.
The Heart -Two separate circulatory loops -Pulmonary circ. Heart to lung and back -right side of heart is responsible -Systemic circ. Heart to body and back -left side of heart is responsible -Atria: (atrium singular) chambers that receive blood -Ventricles: thicker walls, pump blood away from heart
Path of blood flow (abbreviated) 1.Vena Cava’s (I and S) return blood from body to Rt. Atrium 2.Rt. Atrium to Rt. Ventricle 3.Rt. Ventricle pumps to the pulm. Art. And to the lung 4.Rt and Lft lung perform gas exchange 5.Pulm. Veins return oxygen rich blood to Lft. Atrium 6.Lft Atrium to lft ventricle 7.Out through the Aorta (largest artery of the body)
- Coronary arteries: carry oxygen rich blood to the heart (provides needed oxygen to pump heart).
- Sinoatrial node: in upper rt atrium. Responsible for contraction of the heart (it is the pacemaker of the heart).
-Cells that make up the sinoatrial node, “fire” electrical stimulus at a regular rhythm. Each stimulus is followed by a contraction. -Heart contractions average about 72 times per minute. Blood pressure -Heart disease is one of the leading causes of death among people in the US -BP: is the force exerted by blood as it moves through blood vessels. -Expressed in terms of- millimeters of mercury. -Usually reported as the systolic (top) over the diastolic (bottom) pressures. -Systolic: pressure when the heart contracts/blood flows threw arteries -Diastolic: pressure exerted when the heart relaxes.
-Normal blood pressure is 120/80 mm Hg. -Pulse: series of pressure waves within an artery, an indicator of heart rate. -EKG: electrocardiogram, machine used to monitor heart function. -Heart attack: occurs when an area of the heart muscle stops working. (the area dies) -Stroke: When an area of the brain dies (because the artery as popped or clotted and blood can’t get to the area) -Factors contributing to: -Cigarettes -Lack of physical activity -Diet high is saturated fats -Unmanaged stress
How to tell if someone is having a stroke: F.A.S.T F: face drooping. You ask the person to smile, if one side droops, call 911 A: arm weakness. Have them raise their arms, if one side doesn’t go up, call 911 S: slurring. Ask to repeat a simple sentence, slurring, call 911 T: Time. Is of the essence. Any of the above, call 911
How to tell if someone is having a heart attack: -Most important is that men and women HA’s are not the same -IT usually isn’t like in the movies!!! -Every person could be different, if suspected, then act, TIME is critical -Some examples: -Chest discomfort or pain -Discomfort in other parts of the body -Arms, neck, jaw -Shortness of breath -Nausea, clamminess, sweating -Extreme weakness and fatigue (especially if it is sudden)
The Respiratory System -Gas exchange is the way your body obtains and releases gases. -In through the mouth or nose -About 21% is oxygen gas -Hairs in your nose help filter dust and particles. -Tissues in nasal cavity moisten and warm the air Vocab. for the path of air: -Pharynx: tube, passage way from nose and mouth. -Larynx: next part, also called the voice box. -Epiglottis: covers the opening to the larynx when you swallow foods and liquids.
-Trachea: long, straight tube in chest cavity, also called the windpipe, divides into two bronchi, which lead to each lung. -Bronchi divide into smaller tubes called bronchioles. -Alveoli: clusters of air sacs, smallest bronchioles, where gas exchange occurs. -Cells, lining the bronchi, secrete mucus, that traps foreign particles, which is directed upward, by cilia, where it is swallowed and digested. The lungs -One of the largest organs in the body -Diaphragm: below longs, powerful muscle, aids in respiration.
Breathing -inhalation: rib muscles contract, diaphragm contracts, moving downward. Volume on chest increases, this reduces air pressure within the cavity below atmospheric pressure. Air flows from high to low pressure, so therefore air is drawn into the lungs. -Exhalation: passive process, rib cage and diaphragm muscles relax, returns ribs and diaphragm to normal position, decreases volume in chest cavity thus increasing air pressure in lungs, now pressures are reversed, so air is forced out. What controls how fast we breathe? -Receptors in brain monitor levels of oxygen and carbon dioxide -Carbon dioxide levels have a greater effect on breathing -More CO2 levels, the harder/deeper you breathe
Oxygen transport (detailed steps on page 888) 1.O2 reaches lungs 2.O2 diffuses, via alveoli, into pulmonary capillaries 3.O2 rich blood goes to heart, then out to body 4.O2 diffuse into cells for cellular respiration 5.CO2 presence changes RBC affinity for O2, CO2 diffuse from cells to blood 6.CO2 carried to heart (in the form of HCO3- ions) 7.Heart pumps to lungs 8.CO2 expelled.
The forms of CO2 in transport CO2 is transported in 3 different forms 1.Dissolved in blood plasma (about 7%) 2.Attached to hemoglobin (about 23 %) 3.Carried as a bicarbonate ion, HCO3- (about 70%)
Respiratory Diseases Asthma: chronic (persisting for a long time) condition in which the bronchioles of the lungs become inflamed. Emphysema: chronic pulmonary disease resulting from a chemical imbalance that destroys elastic fibers in the lungs. Smoking is the number one cause (90%). Lung Cancer: One of the leading causes of death in the world today. Abnormal cell growth in lung tissue. Smoking is the major cause. Only 15% of patients diagnosed live more that 5 years.