2Outline - Respiratory System Function of the respiratory systemParts of the respiratory systemMechanics of breathingRegulation of breathingDisorders of the respiratory system
3Respiratory system Function The function of the respiratory system is to bring in oxygen to the body and remove carbon dioxide.
4The Respiratory System Breathing moves air in and out of the lungs.External respiration is the exchange of oxygen and carbon dioxide between the lungs and the blood.Gas transport moves oxygen and carbon dioxide between the lungs and the body tissues.Internal respiration is the exchange of oxygen and carbon dioxide between blood and the body tissues.Oxygen transportCarbon dioxide transportLungsGas diffusionGas diffusionTissueFigure 14.1
5This type of tissue covers and lines body parts ConnectiveEpithelialMuscleNervous
6Cells lining respiratory tract Lined by pseudostratified ciliated columnar epithelial cells. The cilia sweeps mucus, germs and debris toward the throat.Mucas produced by goblet cells.Smoking damages the ciliated cells8-4
10The Respiratory System UPPER RESPIRATORY SYSTEMSinuses• Cavities in skull• Lighten head• Warm and moisten air• Filters, warms, and moistens airNasal cavity• Produces mucus• Filters, warms, and moistens air• OlfactionPharynx• Passageway for air and foodRESPIRATORY MUSCLES• Cause breathingIntercostal musclesDiaphragm• Muscle sheet between chest and abdominal cavities with a role in breathing• Move ribs during breathingFigure 14.2 (1 of 2)
11The Respiratory System LOWER RESPIRATORY SYSTEM • Exchanges gasesEpiglottis• Covers larynx during swallowingLarynx• Air passageway• Prevents food and drink from entering lower respiratory system• Produces voiceLungs• Structures that contain alveoli and air passageways• Allow exchange of oxygen and carbon dioxide between atmosphere and bloodBronchi• Two branches of trachea that conduct air from trachea to each lungTrachea• Connects larynx with bronchi leading to each lung• Conducts air to and from bronchiBronchioles• Narrow passageways to conduct air from bronchi to alveoliAlveoli• Microscopic chambers for gas exchangeFigure 14.2 (2 of 2)
12moisten the air entering the lungs smell 1. Nasal cavityFunctions:filterwarmmoisten the air entering the lungssmell8-3
13Mucus membranes - secrete sticky mucus to trap germs & debris. 1. Nasal cavityParts of the nasal cavity:Mucus membranes - secrete sticky mucus to trap germs & debris.Contains olfactory receptor cells for the sense of smellSinuses – air filled cavities, warm and moisten air8-3
142. PharynxFunctions - is a passageway for air, liquids, and food. (swallowing begins here). Connects the nasal cavity to the esophagus and the larynxTonsils are found here – lymphatic tissue that protects against infection8-4
15Functions Connects the pharynx to the trachea 3. LarynxFunctionsConnects the pharynx to the tracheaContains vocal cords used to generate soundPrevents food from entering lower respiratory tract8-4
16Structure made from cartilage 3. LarynxStructure made from cartilageEpiglottis closes the trachea when swallowing8-4
17FIGURE 14.5aThe larynx, commonly called the voice box or Adam's apple, is an adjustable entryway to the trachea and the source of the voice. (a) The epiglottis is open during breathing but covers the opening to the larynx during swallowing to prevent food or drink from entering the trachea. (b) The vocal cords are the folds of connective tissue above the opening of the larynx (the glottis) that produce the voice.
18FIGURE 14.5bThe larynx, commonly called the voice box or Adam's apple, is an adjustable entryway to the trachea and the source of the voice. (a) The epiglottis is open during breathing but covers the opening to the larynx during swallowing to prevent food or drink from entering the trachea. (b) The vocal cords are the folds of connective tissue above the opening of the larynx (the glottis) that produce the voice.
19Windpipe held open by concentric rings of cartilage 4. TracheaWindpipe held open by concentric rings of cartilageFunction – Connects the larynx to the bronchi.8-4
20Trachea leads to the bronchial tree: Bronchi (bronchus)BronchiolesAlveoli (alveolus).8-4
227. AlveoliSacs at the end of the bronchioles, they are surrounded by blood capillaries .Function: It is here that the oxygen diffuses across the membrane into the capillaries, and carbon dioxide goes from the capillaries to the inside of the lungs.8-6
23Alveoli Lungs - have about 300 million alveoli The structure of the alveoli increases surface area of lungFor alveoli to function properly they are coated with phospholipid molecules called surfactant that keep them open
28The tube connecting the larynx to the primary bronchi is pharynxtracheabronchiolesalveoli
29Common passageway for air, food and drink pharynxtracheabronchiolesalveoli
30Conduct air from the trachea to the bronchioles pharynxtracheabronchialveoli
31Gas exchange takes place here pharynxtracheabronchiolesalveoli
32Which cavity is the lung located in? AbdominalPericardialPleuralDorsal
33Inhalation Inhalation Air flow Rib cage moves up and out Intercostal muscles contractDiaphragm contracts and flattensDiaphragm contractsThe chest cavity increases in size, and pressure within the lungs decreases.The lungs expand, and air moves in.(a)Figure 14.9a
34InhalationWhen the diaphragm and intercostal muscles contract, the volume of the thoracic cavity increases, causing the pressure in the lungs to decreaseInhalation is also called inspiration
35Exhalation Exhalation Air flow Rib cage moves down and inward Intercostal muscles relaxDiaphragm relaxes and moves upwardDiaphragm relaxesThe chest cavity decreases in size, and pressure within the lungs increases.The lungs recoil, and air moves out.(b)Figure 14.9b
36Exhalation Exhalation = Expiration When the same muscles relax, volume of the thoracic cavity decreases, pressure in the lungs increase
37Air VolumesThe volume of air inhaled or exhaled during a normal breath is called the tidal volumeTidal volume is usually around 500 mlThe volume of air moved into and out of the lungs is an indication of health
38Air Volumes Inspiratory reserve volume = forced inhalation volume Expiratory reserve volume = forced exhalation volumeResidual volume is the amount of air left in the lungs after forced exhalationVital capacity is the amount of air brought in and out of the lungs during forced breathing
40Gas Exchanges in the Body Remember that O2 enters and CO2 leaves the lungs = External respirationThen O2 and CO2 is exchanged between the blood vessels and tissues = Internal RespirationThis gas exchange is due to diffusion8-14
41Oxygen Transport Oxygen is transported on Hemoglobin. When Oxygen is bound to hemoglobin, then it is called Oxyhemoglobin8-15
42Carbon Dioxide Transport CO2 is transported dissolved in the plasma (10%)CO2 is bound to hemoglobin (20%)CO2 is converted to bicarbonate ions (70%)8-14
44Diffusion of Gasses: Alveoli and Capillaries Figure (2 of 2)
45Diffusion of Gasses: Capillaries and Tissues Figure (1 of 2)
46Regulation of Breathing Normally we breath ventilations per minute.This rate is controlled by the medulla oblongata region of the brain. Nerves transmit signal to the diaphragm and muscles.Chemoreceptors in the medulla oblongata and arteries detect levels of CO2 and O2 in the blood, controlling the rate and depth of breathing.8-12
47Respiratory Disorders Common coldFluPneumoniaStrep ThroatTuberculosisBronchitisAsthmaEmphysemaLung Cancer8-16
48Respiratory Disorders – Common Cold The common cold - Caused by several types of viruses.Symptoms: runny nose, sore throat, sneezing, nasal dischargeTreatment: rest and plenty of fluidsPrevention: wash your hands
49Respiratory Disorders - Flu The flu is caused by the Influenza viruses but there are many variants of these virusesSymptoms: Similar to colds but appear suddenly and more severe. Usually have fever and chills, may have muscle aches, headache, and weakness.Treatment and prevention – same as coldCan take drugs to ease symptoms and antiviral medications may ease symptoms
50Respiratory Disorders - Pneumonia Pneumonia is an inflammation of the lungs that causes fluid to accumulate in the alveoli, reducing gas exchangeUsually caused by a viral or bacterial infectionSymptoms: fever, chills, chest pain, cough, shortness of breath.Treatment depends on cause – bacteria can be treated with antibiotics.
51Respiratory Disorders Strep throat Strep throat is caused by Streptococcus bacteriaCan lead to rheumatic fever which can damage heart and kidney diseaseSymptoms: Sore throat accompanied by swollen glands and feverTreatment: antibiotics
52Respiratory Disorders - Tuberculosis Tuberculosis is caused by a bacteria = mycobacterium tuberculosis.Bacteria spread through airborne transmissionOur body encapsulates the bacteria with a fibrous capsule made of connective tissue to try to protect itself, capsule is called tubercles
53Respiratory Disorders - Tuberculosis Symptoms: similar to flu, weight loss, tired, dry cough.Treatment: Antibiotics must be taken for 6 months to 2 years – some people to stop early – leads to antibiotic resistant strains of bacteria
54Respiratory Disorders - Bronchitis Bronchitis is an inflammation of the mucous membrane of the bronchiCaused by viruses, bacteria, or chemical irritationSymptoms: Inflammation results in the production of excess mucus, which triggers a deep coughTreatment: Depends on cause
55Respiratory Disorders - Asthma The smooth muscles surrounding the bronchi spasm – causing the bronchi to constrict, making it hard to breatheCauses and triggers: allergies, colds, exercise, stress
56Respiratory Disorders - Emphysema Emphysema is caused by the destruction of alveoli, usually by smokingReduction in the surface area available for gas exchange and the increased dead air space results in shortness of breathTreatment - no cure, can supplement with oxygen and drugs can dilate airways.
58Lung CancerLung Cancer is the result of uncontrolled cell division forms a tumorThe smoke irritates the lining of the bronchi.The cilia that normally function to clear dust and particles from the lungs are destroyed.Often caused by inhaled carcinogens, including those found in tobacco smoke. Between 85 – 90% of lung cancer is from smoking.
59Lung CancerLung cancer is more common in men, but as more women are smoking, the rate of lung cancer in women is rising. Women are more at riskMany compounds in the smoke are cancer promoters, they trigger the progression of cancer in cells.8-16
60Effects of SmokingThe 5-year survival rate is 13%. Smoking can cause cancers of other parts of the respiratory system.8-16
61Effects of Smoking on Pregnancy Cigarette smoke contains CO, the fetal blood has a higher affinity for CO than the mothers blood, so CO builds up in the fetuses body.Nicotine is also passed into the fetus, stimulating the developing nervous system.Men smoking can damage the DNA in their sperm and pass genetic mutations to their offspring.8-16
64Figure: 14A-01aTitle:Cigarette smoking reduces life expectancy.Caption:(a) Smoking causes more than 400,000 deaths each year in the United States, more people each year than the combined number of deaths due to AIDS, alcohol, drugs, car accidents, murder, and suicide. These data are from a report from the Centers for Disease Control and Prevention in The number of deaths from cigarette smoking have increased since then, but the relative importance of each cause of death remains similar.
65Figure: 14A-04Title:Tobacco use and lung cancer.Caption:Lung cancer usually takes about 20 years to develop. Notice that the number of deaths from lung cancer increases and decreases with tobacco use with about a 20-year delay. The lung cancer death rate of females is lower than that of men because there are fewer female smokers than there are male smokers. Source: Death rates: U.S. Mortality Public Use Tapes, , U.S. Mortality Volumes, , National Center for Health Statistics, Centers for Disease Control and Prevention, Cigarette consumption: U.S. Department of Agriculture,
66Figure: 14A-07Title:Death rate due to heart disease among nonsmokers and smokers.Caption:Notice that the death rate from heart disease increases with the number of cigarettes smoked per day. People who smoke over a pack per day have more than twice the risk of death due to heart disease than do people who have never smoked. In any case, a smoker who successfully quits is much less likely to die of heart disease than if the smoking habit continues.
67What is the smoking policy on campus? You can smoke anywhereYou can smoke anywhere outsideYou can smoke at designated spotsNo smoking on campus
68Do you think smoking should be allowed on campus? YesNo
69Do you smoke?NeverUsed to, but quitSmoke, but trying to quitSmoke
70Important Concepts Read Ch 15 What is the function of the respiratory system?What is the location and function of the all the parts of the respiratory system?What are the parts of the nasal cavity and their functions?What are the parts of the larynx and their functions?
71Important ConceptsWhat cell types lines the trachea, what are their functions, be able to discus how smoking effects this tissue?Where does the exchange of gases occur in the lungs?What cavity contains the lungs?What controls the rate of breathing?Be able to discuss the mechanics of breathing?
72Important Concepts How is oxygen carried in the blood? How is carbon dioxide carried in the blood, know all the ways, and the which is the predominate mode? (You don’t need to know the chemical equation of bicarbonate formation)What is the diaphragm and what is its function?
73Important ConceptsBe able to discuss the disorders of the respiratory system including the description, symptoms, cause, and treatments.How does smoking effect pregnancy?