Copyright Pearson Prentice Hall Biology Copyright Pearson Prentice Hall

37-3 The Respiratory System Copyright Pearson Prentice Hall

Purpose and Function of the System TWO MAIN FUNCTIONS 1) To put Oxygen (O2) into the blood. 2) To get the carbon dioxide (CO2) out of the blood/body. Why does our body need the Oxygen?? At our cells it combines with glucose (our food) to form usable ATP energy (through cell respiration).

The Human Respiratory System The respiratory system consists of the: nose pharynx larynx trachea (epiglottis) bronchi bronchioles lungs diaphragm Copyright Pearson Prentice Hall

The Human Respiratory System Pharynx Nose Larynx Trachea Mouth Lungs Epiglottis Bronchus Bronchioles The respiratory system is responsible for the exchange of oxygen and carbon dioxide. Air moves through the nose, pharynx, larynx, trachea, and lungs. After reaching the lungs, the trachea branches into smaller and smaller tubes called bronchioles, which end in alveoli, or air sacs. Diaphragm Copyright Pearson Prentice Hall

The Human Respiratory System Pharynx Nose MOUTH AND NOSE Mucus moistens air and traps particles of dust or smoke. Cilia sweep particles and mucus to the throat. Mucus and particles are either swallowed or spit out. The respiratory system is responsible for the exchange of oxygen and carbon dioxide. Copyright Pearson Prentice Hall

The Human Respiratory System Pharynx Nose Pharynx (a.k.a = throat) cavity in back of mouth that leads to the place where your esophagus and larynx meet The respiratory system is responsible for the exchange of oxygen and carbon dioxide. Copyright Pearson Prentice Hall

The Human Respiratory System Trachea, or windpipe. Built of strong cartilage rings. The epiglottis covers the entrance to the trachea when you swallow. Trachea Epiglottis The respiratory system is responsible for the exchange of oxygen and carbon dioxide. Copyright Pearson Prentice Hall

The Human Respiratory System Larynx   Larynx a.k.a. = voicebox At the top of the trachea. It contains two elastic folds of tissue called vocal cords. The respiratory system is responsible for the exchange of oxygen and carbon dioxide. Air moves through the nose, pharynx, larynx, trachea, and lungs. Copyright Pearson Prentice Hall

The Human Respiratory System Bronchi two large passageways in the chest cavity Each bronchus leads into one of the lungs. Lined with cartilage and ciliated Lungs Bronchus The respiratory system is responsible for the exchange of oxygen and carbon dioxide. Air moves through the nose, pharynx, larynx, trachea, and lungs. After reaching the lungs, the trachea branches into smaller and smaller tubes called bronchioles, which end in alveoli, or air sacs. Copyright Pearson Prentice Hall

The Human Respiratory System Bronchioles. smallest air tubes which branch off from the bronchi and end at the alveoli or air sacs Bronchioles The respiratory system is responsible for the exchange of oxygen and carbon dioxide. After reaching the lungs, the trachea branches into smaller and smaller tubes called bronchioles, which end in alveoli, or air sacs. Copyright Pearson Prentice Hall

The Human Respiratory System Alveoli site of respiratory gas exchange by diffusion resemble bunches of grapes Alveoli Bronchiole The respiratory system is responsible for the exchange of oxygen and carbon dioxide. After reaching the lungs, the trachea branches into smaller and smaller tubes called bronchioles, which end in alveoli, or air sacs. Copyright Pearson Prentice Hall

The Human Respiratory System moist surface aids exchange each alveolus is surrounded by capillaries (oxygen in--carbon dioxide out) Pulmonary artery Pulmonary vein The respiratory system is responsible for the exchange of oxygen and carbon dioxide. Capillaries Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Gas Exchange Gas Exchange Gas exchange takes place in the alveoli. Oxygen diffuses into the blood. O2 Gas exchange occurs by diffusion across the membrane of an alveolus and a capillary. Capillary Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Gas Exchange Carbon dioxide in the blood diffuses into the alveolus. O2 CO2 Gas exchange occurs by diffusion across the membrane of an alveolus and a capillary.  Capillary Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Breathing HOW YOUR LUNGS WORK… The air pressure around us is what forces your lungs to fill up. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Breathing Diaphragm sheet of muscle separating the thoracic (chest) cavity from the abdominal cavity During inhalation the rib cage rises and the diaphragm contracts, increasing the size of the chest cavity. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Breathing During inhalation, the diaphragm contracts and the rib cage rises up. This expands the volume of the chest cavity. During inhalation the rib cage rises and the diaphragm contracts, increasing the size of the chest cavity. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Breathing When the rib cage lowers and the diaphragm relaxes, pressure in the chest cavity is greater than atmospheric pressure. Air is pushed out of the lungs. Air Exhaled Rib cage lowers During inhalation the rib cage rises and the diaphragm contracts, increasing the size of the chest cavity. Exhalation Copyright Pearson Prentice Hall

How Breathing Is Controlled Breathing is controlled by the medulla oblongata. The medulla oblongata monitors carbon dioxide in the blood. As carbon dioxide increases, nerve impulses make the diaphragm contract, bringing air into the lungs. The higher the carbon dioxide level, the stronger the impulses. Copyright Pearson Prentice Hall

Some Respiratory System Malfunctions

pneumonia: alveoli fill with fluids and mucus resulting in coughing and breathing difficulties

asthma: allergic reaction in which bronchiole contractions create breathing difficulties

emphysema: air sacs lose their elasticity and breakdown resulting in a loss of respiratory surface in the lungs --shortness of breath is the chief symptom (smoking frequently leads to this disorder)

Copyright Pearson Prentice Hall 37-3 Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 37-3 Air passes through the trachea into two large passageways in the chest cavity known as the bronchi. alveoli. epiglottis. bronchioles. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 37-3 The function of the cilia lining the respiratory surfaces is to improve the amount of oxygen and carbon dioxide exchanged in the lungs. cover the opening of the trachea when you swallow. move air in and out of the lungs. sweep trapped particles and mucus away from the lungs. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 37-3 Oxygen diffuses from the alveolus into the blood because blood entering the capillaries of the lungs is oxygen-poor. blood entering the capillaries of the lungs is oxygen-rich. air entering the lungs has more carbon dioxide than oxygen. air entering the lungs has less oxygen than is found in the blood. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 37-3 A stimulant drug found in tobacco that increases the heart rate and blood pressure is tar. carbon monoxide. nicotine. carbon dioxide. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 37-3 A respiratory disease that results in the loss of elasticity in the tissues of the lung is chronic bronchitis. lung cancer. emphysema. pneumonia. Copyright Pearson Prentice Hall

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