THE RESPIRATORY SYSTEM

VENTILATION & RESPIRATION

VENTILATIONVentilation = Breathing – NO gas exchange

Inspiration & Expiration StepsA. Diaphragm contracts & lowers

B. Intercostals contract & lift ribs

C. Lungs expandD. Increased volume in lungs = decreased pressure in lungs

E. Air moves in (high to low pressure)

F. Expiration = opposite!

VENTILATION VISUALS

http://oac.med.jhmi.edu/res_phys/Encyclopedia/AlveolarPressure/AlveolarPressure.HTML

http://www.mhhe.com/biosci/genbio/animation_quizzes/animate_11.htm

Be sure to look at these sites: copy & paste the URL’s

VENTILATION VISUALS

http://oac.med.jhmi.edu/res_phys/Encyclopedia/AlveolarPressure/AlveolarPressure.HTML

http://www.mhhe.com/biosci/genbio/animation_quizzes/animate_11.htm

Be sure to look at these sites: type in the URL’s

Lung Volume & Capacities

AssignmentUse text pg 497Label all terms on chart (you can use letters)BRIEFLY define all terms in space around chartDefine “Dead Space”

☆ This will be graded next class with an open-note quiz - you will not turn it in!

RESPIRATION Respiration = actual exchange of gases

1. External = diffusion of O2 CO2 between alveoli blood

2. Internal = diffusion of O2 CO2 between blood cells

3. Cellular = cells use O2 to burn food (glucose) & produce CO2 as waste

Types:

http://www.mhhe.com/biosci/genbio/animation_quizzes/animate_96.htm

Copy & Paste this URL!

RESPIRATION WRAP-UP

TRANSPORTATION OF GASES: Oxygen

98% of O2 in blood is bound to Hemoglobin (Hb)

Hb + O2 HbO2

How tight the Hb holds on to O2 depends on:1. pH2. Temperature3. Amount of CO2 & O2 present

Ex: In muscles at exercise

TRANSPORTATION OF GASES: Carbon DioxideCan be transported 1 of 3 ways:

1. Dissolved in the plasma – 7%

2. Directly bound to Hb – 23%

3. Converted to carbonic acid & then bicarbonate ion on the RBC – 70%

CO2 + H20 H2CO3 HCO3- +H+

☆ Respiratory Rates are VERY susceptible to levels of CO2 in the blood: too high = too acidic – body response = increased breathing

RESPIRATORY DISORDERS

VOCABULARYApnea = absence of breathing

Dyspnea = difficulty breathing

Hypoxia = decreased O2 to cells

☆ Lung Cancer = #1 cause of cancer death in U.S. & >90% of all cases are b/c of smoking!

RESPIRATORY DISORDERS

Emphysema – degeneration of alveolar walls (permanent)

Normal Alveoli

RESPIRATORY DISORDERS

Asthma – spasm of bronchioles

RESPIRATORY DISORDERS

Pneumonia – viral/bacterial infection of alveoli walls

RESPIRATORY DISORDERS

Pulmonary edema – fluid in alveoli - usually from another condition (like a failing heart!)

RESPIRATORY DISORDERS

Cystic Fibrosis – genetic disorder fills lungs with mucus – death by age 30 usually!

RESPIRATORY DISORDERS

Tuberculosis(TB) – bacterial infection- scarring of lungs/death ☆ #1 infectious disease killer in world ☆ > 2 billion infected & becoming resistant to meds!