Post on 21-Dec-2015
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1.Breathing (Pulmonary Ventilation)2.External Respiration3.Internal Respiration 4.Cellular Respiration
4 PROCESSES
• act as resonance chambers for speech • mucosa warms and moistens the incoming air• lightens facial bones
Connects nasal cavity and mouth to larynx and esophagus1) nasopharynx- air passage
Eustatian tubeAdenoids (pharyngeal) tonsils- mass of lymphoid tissue• traps and destroys pathogens• produces lymphocytes• helps fight infection
2) oropharynx- serves as a common conduit for air and foodpalatine and lingual tonsils
3) laryngopharynx- accommodates both ingested food and air• located at junction where tracheae and esophagus
splits• continuous with esophagus
Epiglottis- flexible elastic cartilageattached to the wall of the pharynx near the base of the
tongue Larynx- voice box; thyroid cart. that attaches to hyoid
bone superior and cricoid inferior• Provides open airway • Junction for food and air• Voice production
Laryngopharynx
Oropharynx
Nasopharynx
Olfactory tract
Olfactory bulb
Nasalconchae
Route ofinhaled air
Olfactoryepithelium
16 C-shaped rings of hyaline cartilage (thyroid +cricoid + tracheal cartilage's, includes epiglottis (elastic cart) make up larynxFunction- hold trachea open
Laryngitis- inflammation of the vocal cords resulting in inability to speak; due to voice overuse, very dry air, bacterial infection, and inhalation of irritating chemicals
The TracheaThe Trachea
hyaline
cartilage ring
esophagus
posterior
anterior
lumenMucus membrane
submucosa
adventiti
a
The Trachea
The Trachea
Epithelial Lining of the Trachea
mucus
cilia
• True vocal cords are inferior to false vocal cords• Sound is produced when expelled air is passing
through the larynx over the vocal cords
2 muscles involved with breathing: • external intercostal muscles • diaphragm
Breathing controlled by:• phrenic nerve from medulla• pons
Lung Ventilation
Inspiration
760 mm Hg
756 mm HgNegative pressure draws air in
Lung Ventilation
Expiration
768 mm Hg
Positive pressure forces air out
Lung Volumes
Tidal Volume- 500 ml
Vital Capacity- 4800 ml
Residual Volume- 1200ml
Total Lung Capacity- 4200-6000ml
IRV- 3100 ml
ERV- 1200ml
Dead Space- 150 ml
What factors affect lung volume?
What happens to TV, IRV, ERV, & VC during exercise?
• TV • IRV and ERV • TLC and VC- doesn't change
Breathing Centers in the Brain
Regulation of Breathing
medulla oblonga
ta
pons
CO2 and H+
triggers breathing reflex in medulla, not presence of O2
phrenic
vagus
Restrictive- more diff. to get air in to lungs• Loss of lung tissue• Decrease in lungs ability to expand• Decrease in ability to transfer O2 and CO2 in
blood
Diseases:Fibrosis, sarcoidosis, muscular disease, chest
wall injury, pneumonia, lung cancer, pregnancy, obesity
VC, TLC, RV, FRC
Obstructive- more diff. to get air out of lungs• Airway narrows• Increase in time it takes to empty lungs
Diseases:Emphysema, chronic bronchitis, asthma
VC, TLC, RV, FRC
Chronic bronchitis- (obstructive) inhaled irritants lead to chronic excessive mucous production and inflammation and fibrosis of that mucosa; the amt of air that can be inhaled; use bronco- dilators and inhalers
Emphysema- (obstructive and restrictive) enlargement of alveoli; alveolar tissue is destroyed resulting in fewer and larger alveoli; inefficient air exchange; smoker's disease; amt of air that can be exhaled
Asthma- (obstructive disorder) cold, exercise, pollen and other allergens; from 1979-1989 the number of asthmatic deaths doubles
Tuberculosis (TB)- (restrictive) infectious disease cause by bacterium Mycobacterium tuberculosis. Spread through air borne bacteria from infected person's cough. Total lung capacity declines
Symptoms: fever night sweats, wt. loss, racking cough, and spitting up blood
Polio- TLC declines (restrictive)
Eliminated in U.S. and Western Hemisphere
Still exists in Africa
Lung cancer- promoted by free radicals and other carcinogens; very aggressive and metastasizes rapidly
Normal lung Smoker’s lung
The total pressure of a gas exerted by a mixture of gas is the sum of the gases exerted independently.
Air % partial pressure (mm Hg)N2 78.6 597O2 21.0 159CO2 0.04 0.3H2O 0.46 3.7Total 100 760
Partial pressure is directly related to its % in the total gas mixture. E.g., at 1 atm PO2 = 159 mm Hg
When a mixture of gas is in contact w/a liquid, each gas will dissolve in the liquid in proportion to its partial pressure.
Gasses can go in and out of solution
e.g., open soda, get CO2 bubbles (CO2 is under pressure)
It is caused when N2 enters the blood circulation and the tissues.
When extra N2 leaves the tissues, large bubbles form. N2 bubbles can travel throughout the system and into the lungs and blood routes.
Treatment: hyperbaric chamber
Erythrocytes
Function- transport respiratory gases
Lack mitochondria. Why?
Hemoglobin Structure
1 RBC contains 250 million hemoglobin molecules
Hemoglobin- quaternary structure2 chains and 2 chains
Uptake of Oxygen by Hemoglobin in the Lungs
High Concentration of OHigh Concentration of O2 2 in Blood Plasmain Blood Plasma
High pH of the Blood PlasmaHigh pH of the Blood Plasma
O2 binds to hemoglobin to form oxyhemoglobin
O2
oxyhemoglobin
OO2 2 pickup COpickup CO22 release release
Unloading of Oxygen from Hemoglobin in the Tissues
Low Concentration of OLow Concentration of O2 2 in Blood Plasma in Blood Plasma
Lower pH of the Blood PlasmaLower pH of the Blood Plasma
When OO22 is releaseddeoxyhemoglobin
OO2 2 releaserelease COCO22 pickup pickup
Carbon Dioxide Chemistry in the Blood
COCO22 + H + H22O O H H22COCO3 3 HCOHCO33-- + H + H++
carbonic carbonic acidacid
bicarbonatebicarbonateionion
enzyme = carbonic anhydraseenzyme = carbonic anhydrase
Transport of Carbon Dioxide from the Tissues to the Lungs
• 60-70% as bicarbonate dissolved in the plasma (slow reaction)• 7-10% dissolved in the plasma as CO2
• 20-30% bound to hemoglobin as HbCO2
CO2 + hemoglobin HbCO2
Haldane Effect- the amt of CO2 transported in the blood is markedly affected by the degree of oxygenation of the blood
The lower the PO2 and hemoglobin saturation w/O2, the more CO2 that can be carried by the blood.
CO poisoning (hypoxemia hypoxia) • CO binds 200x more readily w/hemoglobin• acts as a competitive inhibitor
symptoms: cherry red lips, confused, headachedoes not produce characteristic signs of hypoxia
(cyanosis and respiratory distress)
treatment: hyperbaric chamber
1. Heart rate slows2. Blood flow to extremities
constricted3. Blood and water allowed to
pass through organs and circulatory walls to chest cavity.
• Short term, rapid, deep breathing beyond the need for the activity
• Lowers the level of CO2 in blood (hypocapnia or hypocarbia)
INQUIRY
1. Identify the lipoprotein molecule that reduces surface tension within the alveoli so they do not collapse during exhalation.
2. Even after the most forceful exhalation, a certain volume of air remains in the lungs. What is the volume of air called?
3. Describe the physical structure of alveoli.4. What structures warm and moisten incoming
air?5. What body cavity are the lungs located?6. What tissue lines the lungs?7. What stimulates the breathing response?8. Calculate total lung capacity given:RV= 1000, TV = 500, ERV = 1100, IRV = 2500,
VC= 4100