Term
| Why do animals need gas exchange? |
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Definition
to make ATP
through glycolysis and cellular respiration |
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Term
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Definition
gas pressure depend on the number of particles and their kinetic energy
the total system pressure is the sum of all the components' pressure
in a gas mix, the total pressure=sum of all partial pressures |
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Term
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Definition
| the contribution each gas component makes to a total pressure system |
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Term
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Definition
the tendency of molecules to move from high to low concentrations
Frick's law of diffusion equation
diffusion is the ultimate rate limiting factor in animals in the ability to exchange O2 and CO2
temperature changes pressure, pressure drives diffusion |
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Term
| Basic components of a Gas-Transfer System (4) |
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Definition
1. Ventilating media (air or water); in environment (150 mm Hg) and in physiological systems (130 mm Hg)
2. Exchange surface
3. Fluid delivery system
4. Tissue exchange system |
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Term
| Basic Gas-Exchange System Designs (4) |
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Definition
1. Skin
2. Gills
3. Lungs
4. Tracheal System |
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Term
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Definition
gas-exchange system
no bulk transfer of gases via blood
in some animals, is only gas-exchange mechanism |
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Term
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Definition
in aquatic organisms
bulk transport of gases
challenges: O2 concentration in air is 20x higher than in water, and O2 diffuses 8000x more rapidly in air than in water
Anatomy:
gill arches hold gill filaments for increased surface area
mechanism pushes water over gills constantly for consistent gas-exchange
most gills are internal, few are external
Buccal chamber: sucks water into system
gill arches: support gill epithelia
opercular cavity: space between gill arches and valve
opercular valve: controls access between intestinal/external environment
Ventilation:
water into Buccal cavity; mouth open, valve closed
close mouth, raise tongue, open valve
pressure increases, pushes water through gills and out valves |
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Term
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Definition
in air breathing organisms
bulk transport of gases |
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Term
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Definition
in insects (air breathing organisms)
no bulk transport, oxygen goes to individual cells |
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Term
| common themes in gas-transfer systems (3) |
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Definition
1. Maintain/create a surface area to volume ratio
2. Decrease diffusion distance
3. Concentration of O2 does not affect movement |
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Term
| Blood flow in gills (3 types) |
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Definition
1. concurrent: blood and water flow in same direction
2. multicapillary: blood enters in increments, maintaining a low pressure and a high concentration gradient
3. countercurrent: blood and water flow in opposite directions; smaller diffusion distance is lower resistance, change in pressure is constant during flow, maximizes O2 transfer |
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Term
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Definition
Anatomy:
windpipe/trachea: round, open tube that expands into bronchi
bronchi, bronchioles, terminal bronchioles, respiratory bronchioles: branch to increase surface area
alveolar duct: airspace leading into alveolar sac, susceptible to pathogens so lined with cilia and mucous (mucous ladder)
alveolar sac: group of alveoli
alveoli: exchange surface
Pores of Kohn: method of pushing air into alveolar sacs
alveolo-capillary membrane: surface film, capillary endothelium, interstitial space, alveolar epithelium (SMALL diffusion distance outside of alveolar sac)
Lung Epithelium: Type I cells (most prolific, provide diffusion surface), Type II cells (produce surfactants, break surface tension), Type III cells (rare, regulate osmoregulation)
Lung ventilation:
air moves back and forth, in/out of lungs
fluid in thoracic cavity is incompressible
links muscles of the ribs to inhalation: opening/closing ribs cause lungs to open/close, fill/empty
tidal volume: volume of air exchanged
reserve volume: amount of air that you could exchange but are not
residual volume: air that is trapped in alveoli that prevents all air from exiting and lung from collapsing
cause air to mix
air in lungs: pressure of O2 is 100mmHg
air outside of body: pressure of O2 is 150mmHg
air in body cavity: pressure of O2 is 40mmHg |
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Term
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Definition
a protein that allows for up to 4 oxygen molecules to bind and transport in the blood
cannot transport O2 to tissues, ONLY TRANSPORT IN BLOOD
oxyhemoglobin: hemoglobin+O2
deoxyhemoglobin: hemoglobin without O2
methemoglobin: hemoglobin with oxidized iron, incapable of binding O2, must break down
carboxyhemoglobin: hemoglobin+CO2, affinity for CO2 is 200x greater than that for O2
once hemoglobin loses 1 O2 molecule, it's easier to lose the other 3 |
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Term
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Definition
protein that carries O2 from blood into tissues
good for increased need of O2 storage, has high O2 saturation |
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Term
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Definition
increased temperature, decreased O2 affinity
decreased pH, decreased O2 affinity
increased O2, decreased O2 affinity
increased CO2, increased O2 affinity |
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Term
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Definition
change in environment can cause a shift in P50
increased CO2 in blood causes increased acidity in blood (H+), increased acidity causes O2 to disassociate from hemoglobin so myoglobin can bind to O2 and take it to muscle tissues |
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Term
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Definition
| deoxygenated blood has a higher capacity for CO2 transport |
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