Unit Nine - The Respiratory System

Transcription

1 Unit Nine - The Respiratory System I. Introduction A. Definition: the respiratory system consists of the nose, nasal cavity, (throat), (voice box), (windpipe), bronchi and lungs (which contain the alveoli). B. Function: the between the atmosphere, blood, and cells. Cells use oxygen for the metabolic reaction that release energy and provide atp. This process causes a build up of carbon dioxide that needs to be released. Remember how took place in the, this is when the oxygen is consumed and carbon dioxide is produced. In addition to functioning in gas exchange, the respiratory system also contains receptors for the sense of, filters incoming, produces. C. Pathway of Air 1. Nose (nares) 2. Nasal cavity 3. Pharynx (throat) 4. Larynx (voice box) 5. Trachea (windpipe) 6. Bronchi (branch inside lungs to bronchioles) 7. Lungs (contains sacs for gas exchange called alveoli) D. Definitions 1. Mucosa - 2. Cilia - 3. Cilia mucosa lining -

2 E. Diagram of the Human Respiratory System: II. Nose (External nares) A. The external nares or is the name of the two openings that allow air to enter the nasal cavity. III. Nasal cavity (Internal nares) A. The interior of the nose is divided in the middle by the nasal. The nasal cavity is lined by mucous membrane with the three important functions. 1. and moistens the air. 2. The traps incoming foreign particles and found in the mucous membrane pushes the trapped debris toward the throat. 3. Contains receptors for. 4. What might be the cause of a runny nose on a cold day?

3 B. The walls of the nasal cavity have three bony projections called. These increase the for the mucous membrane. C. The top of the nasal cavity contains the olfactory receptors for the sense of. D. The bottom of the nasal cavity consists of a partition called the separating it from the mouth. E. Four paired open into the nasal cavity. The sinuses lighten the skull and they produce which drains into the nasal cavities. F. The nasolacrimal ducts, which from the eyes, also empty into the nasal cavities. IV. Pharynx (throat) A. The pharynx is located behind and connects together the and cavities. B. It functions as a passageway for air and food. C. It has two openings called the auditory (eustachian) tubes that allow the flow of air to and from the. These tubes also drain into the pharynx from the middle ear. D. Why might a sore throat lead to an ear infection such as otis media? E. The pharynx then divides into the larynx (a respiratory passage) to the front and the esophagus (a digestive passage) to the rear. V. Larynx ( ) A. The larynx is a short passageway that connects the pharynx with the. It lies in the middle of the neck in front of the fourth, fifth, and sixth cervical vertebrae. B. The protects the opening to the larynx. Normally the passageway to the respiratory passage below remains. When foods or liquids are swallowed the epiglottis closes over the trachea (lower respiratory passage) forcing the contents back to the esophagus (food tube). C. The vocal cords are formed from on the edges of the larynx. Muscles change the shape of the opening between the folds which changes the sounds produced when air passes through the larynx. D. Why do men typically have a lower range of pitch than women? E. What might be the causes of laryngitis?

4 VI. Trachea (windpipe) A. The trachea functions simply as a passageway for air from the larynx to the bronchi giving it the layman term. B. It is about four inches long and composed of a series of c-shaped rings of, so that each almost encircles the lumen. C. The trachea is lined with. The cilia constantly push mucosa full of bacteria, dust particles, and other debris away from the lungs and up to the throat where it can be swallowed and expelled. D. How might smoking affect the function of the cilia mucosa lining? E. The open ends of the c-shaped rings are adjacent to the. F. Diagram of trachea with esophagus and epiglottis: G. What causes someone to choke and what can be done when an obstruction occurs?

5 VII. Bronchi A. The trachea into two bronchi, each going to a (right and left). Like the trachea, the bronchi are made up of incomplete rings of. B. After entering the lungs, the bronchi divide to form smaller bronchi. VIII. Lungs A. There are lungs, both are fairly large organs. They occupy the cavity and surround the heart. The right lung has lobes, while the left has. B. Each lung has an (the rounded superior end, just behind the clavicle) and three surfaces: 1. surface- the area of the lung that faces the thoracic wall (sternum and ribs). 2. surface (base)- the area of the lung sitting on the upper surface of the diaphragm. The diaphragm arches up forming a dome; this causes the base of the lungs to have a concave surface. 3. surface- the part of the lung facing the heart. The medial surface contains the, the place where all structures entering or leaving the lung pass. C. of the lung- name of given to all the structures that enter or leave the lung at the brings deoxygenated blood to the lungs from the heart carries oxygenated blood back to the heart branches of the trachea, serves as a passageway for air. D. Each lung is enclosed in a double-layered serous membrane. The outer layer is attached to the wall of the thoracic cavity and is called the. The inner layer, called the, covers the lungs themselves. Between these two layers is the. The pleural cavity is filled with slippery serous secretions called the.

6 e. Diagram of the lung surfaces and the hilus of the lung: G. What might the function of the pleural cavity be and where have we before encountered a similar structure? H. What is the condition called pleurisy? I. Inside the lungs 1. As the bronchi branches continue to divide and become smaller, the rings of cartilage and muscle encircles the lumen (they are now called ). 2. The parasympathetic division of the autonomic nervous system, and histamine given off during allergic reactions, causes bronchiole constriction. The sympathetic division and epinephrine cause bronchiole dilation. A. What might happen if this smooth muscle of the bronchioles went into spasm?

7 3. At the end of branches of the bronchioles the membranes are no longer present. A. How will any debris breathed in be removed? 4. The very end branches of bronchioles become. There are millions of these alveoli sacs resembling huge clusters of. The lungs are mostly air spaces and this makes them soft and spongy. 5. The respiratory membrane (air-blood barrier): this barrier allows the exchange of gases between blood in the and air in the. The exchange occurs through simple - O2 into blood and CO2 out of blood. 6. Why so many small alveoli sacs instead of one large one?

8 IX. Diaphragm A. The sheet that separates the thoracic cavity and the abdominal cavity. B. The diaphragm is responsible percent of respiration. C. Respiration involves two processes, (breathing in) and (breathing out). 1. Inspiration A. The diaphragm causing it to flatten pushing down on the abdominal organs. B. The area of the thoracic cavity increases lowering the air pressure surrounding the lungs. C. The air pressure from the outside atmosphere becomes higher than that within the lungs. D. Air from the outside will the open tubes of the respiratory tract and into the lungs. 2. Expiration A. The diaphragm allowing the abdominal organs to force it up into a dome shape. B. The area of the thoracic cavity decreases, increasing the air pressure surrounding the lungs. C. The air pressure inside the lungs becomes higher that of the outside atmosphere. D. Air from within the lungs will the open tubes of the respiratory tract into the outside atmosphere.