View
3
Download
0
Category
Preview:
Citation preview
11.1THE FUNCTION OF RESPIRATION
• Cyctic fibrosis patients can now live into their 40s and beyond
• Can participate in many physical activities
RESPIRATION
• Bring in oxygen, remove CO2 from body cells
• 4 stages
1. Breathing: inspiration and expiration
2. External respiration: gas exchange between lungs and blood
3. Internal respiration: gas exchange between blood and cells
4. Cellular respiration: reactions in cells to release energy
STAGES OF RESPIRATION
Click “play” to watch video
RESPIRATORY SURFACES
• 2 reqiuirements
1. Large enough for quick gas exchange
2. Moist so gas can dissolve
• Different animals evolve different respiratory surfaces and systems
• Common for all is Ventilation: process of drawing/pumping oxygen-containing medium over respiratory surface
TYPES OF RESPIRATORY SURFACES – OUTER SKIN
• Use entire outer skin
• Diffusion of O2 and CO2 in and out of cells from blood
• Must live in moist environments
TYPES OF RESPIRATORY SURFACES – GILLS
• Extensions of folds in the body surface to increase surface area
• Diffusion of O2 and CO2 in and out of cells from blood
• Live in aquatic environments
TYPES OF RESPIRATORY SURFACES – TRACHEAL SYSTEM
• For insects
• Internal system of branching respiratory tracheae (tube)
• Tracheae connects cells directly to environment for gas exchange (blood not required)
TYPES OF RESPIRATORY SURFACES – LUNGS
• For large animals
• Provide more gas exchange
• Contain sacs lined with a moist surface (epithelium)
• Sacs increase surface area
• Blood transports gases to cells by diffusion
AQUATIC GAS EXCHANGE
• Gill users take water into mouth and ventilate over gills
• Dissolved O2 in water diffuse into blood in the gills
• CO2 diffuses out into water
• Counter-current system:
• Water and blood flow in opposite directions
• O2 and CO2 follow diffusion gradients (high low)
TERRESTRIAL GAS EXCHANGE
• Breathing: move air in and out of lungs
• Brain regulates breathing rate and monitors air volume in lungs
• Diaphragm and intercostal muscles :
• Control air pressure inside lungs
• control inhalation and exhalation
• Diaphragm: dome muscle at bottom of thoracic cavity
• Intercostal muscle: rib muscle Click “play” to watch video
AIR PRESSURE IN LUNGS
• Inspiration (inhalation)
• Intercostal muscles and diaphragm contract
• Rib cage moves up and out
• Diaphragm moves down
• Expand thoracic cavity (air-tight)
• Increase volume pressure decrease
• Air from external environment rush into lungs
AIR PRESSURE IN LUNGS
• Expiration (exhalation)
• Opposite of inhalation
• Intercostal muscles and diaphragm relax
• Rib cage moves down and in
• Diaphragm moves up
• Reduce thoracic cavity (air-tight)
• Decrease volume pressure increase
• Forces air out of lungs
play
stop
BREATHING
MEASURING RESPIRATORY VOLUME
Tidal volume:
air volume inhaled and exhaled in a normal breathing movement (body is at rest).
Inspiratory reserve volume:
additional air volume that can be taken into the lungs beyond a regular (tidal) inhalation.
Expiratory reserve volume:
additional air volume that can be forced out of the lungs beyond a regular (tidal) exhalation.
MEASURING RESPIRATORY VOLUME
Vital capacity (total lung volume):
total air volume that can be moved into or out of the lungs.
vital capacity
= tidal volume + inspiratory reserve volume + expiratory reserve volume
Residual volume:
amount of air that remains in the lungs and passageways even after a full exhalation.
SPIROGRAPHS
• Spirometer measures respiratory volume
HOMEWORK
• P.449 #1,3-12,14
Recommended