Partial pressure: the pressure exerted by each type of gas in a mixture, dalton's law, water vapor pressure.
Diffusion of gases through liquids: concentation of gas in a liquid is determined by its partial pressure and its solubility coefficient. Henry's law
physical principles of gas exchange
minute and alveolar ventilation
Minute ventilation : total amount of air moved into and out of respiratory system per minute. Respiratory rate or frequency : number breaths taken per minute. Anatomic dead space : part of respiratory system where gas exchange does not take place.
Alveolar ventilation : how much air per minute enters the parts of the respiratory system in which gas exchange takes place.
residual volume
volume of air remaining in respiration passages and lungs after the most forceful expiration
inspiratory reserve volume
amount of air inspired forcefully after inspiration of normal tidal volume
pulmonary capacities
Inspiratory capacity: tidal volume plus inspiratory reserve volume. Functional residual capacity: expiratory reserve volume plus the residual volume. Vital capacity: sum of inspiratory reserve volume, tidal volume, and expiratory reserve volume . Total lung capacity: sum of inspiratory and expiratory reserve volumes plus the tidal volume and residual volume.
invertebrates respiratory system
Sponges do not have speciliazed respiratory organs. Simple diffusions is enough to support all cells with oxygen. Water flows into a sponge througt side openings and out of the top opening osculum. The water current provides both food and oxygen removes waste products. All of the cells in the sponge obtain their oxygen from the circulated water. Flatwarms also do not need respiratory organs as like lungs or gills, simple diffusion occur for gas exchange.
gills lungs tracheae
There are three general types of respiratory systems, these are: gills, lungs, tracheae. a gill is an evaginated extension of the body surface that can be highly folded to increase the surface area. ıt is covered by a special structure called operculum. An internal circulatory system distrubutes blood through gill and body. The external circulation of water over the gill can be accomplished by pumping movements, by the action of surface ciliated cells, or by moving the gills through water.
a lung in contrast to gill, is an invaginated internalized surface. Lungs are ofter highly folded to maximize their surface area for gas exchange. Trachea are a third type respiratory system used by many air breathing invertebrates particulary arthropods. The trachea branch internally to form numerous small tubes whose blind ends lie close to all cells of the body. http://respiratory-system.blogspot.com
Gills often have a flow of water over their surface that is in the opposite direction to blood flow; ths is countercurrent flow. Birds are very specialized exchange system; there is a one way flow of air through the lungs but blood flow is a one-way essentially crosscurrent rather than countercurrent or co-current.
compostion of air
The composition of normal, dry atmospheric air is 20.95 percent oxygen, 0.03% carbon dioxide and 78.08% nitrogen. The normal atmospheric pressure at sea level is about 760 mmHg.
The total pressure exerted by a gas mixture is equal to the sum of pressures exerted by each constituents gas ( dalton's law)
p02= 159.2 mmHg
pco2= 0.03 mmHg
pN2= 600.6 mmHg
Atmospheric pressure increases markedly underwater.
the atmospheric pressure decreases in high altitude. The metabolism of soil microbes and small soil animals can reduce the fractional oxygen content and elevate the carbodioxide content of soil air. Atmospheric air always contains some water vapor. Water in equilibrium with air will have the sane gas partial pressures as the saturated air but may have considrably different molar concentrations of the gases. Solubility of gases in liquid are different. solubility coefficient depends on the gas, the nature of solvent, temperature and ionic strength. Respiratory system
Diffusion is simply the movement of molecules from one region to another due to their random thermal motion.
functions
- gas exchange: oxygen enters blood and carbon dioxide leaves
- regulation of blood pH: altered by changing blood carbon dioxide levels.
- voice production: movement of air past vocal folds makes sound and speech
- olfaction: smell occurs when airbone molecules drawn into nasal cavity
- protection . against microorganisms by preventing entry and removing them
respiratory system summary
ventilation: movement of air into and out of the lungs. External respiration: gas exchange between air in lungs and blood. transport of oxygen and carbon dioxide in the blood. Internal respiration: gas exchange between the flood and tissues. The function of respiration: ATP synthesized by aerobic metabolism is 20 times larger than the common anaerobic pathways leading to lactic acid.
20 percent of air is oxygen as you know. Oxygen uptake is accompanied by an euqivalent CO2 excretion. Small animals do not require any specialized respiratory structures for oxygen uptake or carbon dioxide loss or an internal circulatory system. A larger body size decreases the body surface area available for respiratory exchange relative to body mass.
The evolution of larger and metabolically more active animals is associated with progressively more complex respiratory structures specialized for gas exchange.
Respiratory System for a high school biology class.
this video explains: Respiratory System for a high school biology class.
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