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 passagepharyngotympanic (auditory) tube- allows middle air pressure

to become equalized to atmospheric pressureAdenoids (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 food

palatine and lingual tonsils3)     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 it closes the glottis in the respiratory tract (trachea)

when food is swallowedLarynx- voice box; thyroid cart. that attaches to hyoid

bone superior and cricoid inferior• Provides open airway • Junction for food and air• Voice production

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 larynx

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

Trachea- held open by rings of hyaline cartilage, so it won't collapse during pressure changes when breathing.

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- 1000-1200ml

Total Lung Capacity- 4400-6400ml

IRV- 2800 ml

ERV- 1000-1200ml

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

ErythrocytesFunction- 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

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 O2 is releaseddeoxyhemoglobin

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 P02 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

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