Difference between revisions of "Respiration in Non-Homeotherms - Anatomy & Physiology"
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| − | {{ | + | {{toplink |
| + | |backcolour = D1EEEE | ||
| + | |linkpage =Cardiorespiratory System - Anatomy & Physiology | ||
| + | |linktext =Cardiorespiratory System | ||
| + | |maplink = Cardiorespiratory System (Content Map) - Anatomy & Physiology | ||
| + | |pagetype =Anatomy | ||
| + | }} | ||
| + | <br> | ||
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==Fish== | ==Fish== | ||
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Gills are in the walls of both sides of the [[Pharynx - Anatomy & Physiology|pharynx]] and are composed of filaments which increase the surface area. | Gills are in the walls of both sides of the [[Pharynx - Anatomy & Physiology|pharynx]] and are composed of filaments which increase the surface area. | ||
| − | When a fish breaths, it takes in water into the mouth, which is then forced out through the gills. A ''' | + | When a fish breaths, it takes in water into the mouth, which is then forced out through the gills. |
| + | |||
| + | A '''Countercurrent Exchange''' system is in place within the gills to make gaseous exchange more efficient. | ||
| − | + | ==Amphibia== | |
| − | + | In amphibian species, the [[Skin - Anatomy & Physiology|skin]] forms the major, and sometimes only respiratory organ. | |
| − | + | The [[Skin - Anatomy & Physiology|skin]] of amphibia is: | |
| + | *Thin | ||
| + | *Poorly keratinised | ||
| + | *Highly vascularised | ||
| + | *Moist to promote diffusion of gases | ||
| − | + | '''Aquatic''' amphibians may also have ''internal gills'' and '''Pharyngeal Slits'''. | |
| − | + | Most Amphibia also have lungs for breathing. This contains interconnecting septa which divide the lumen into '''Faveoli''', compartments which open into a central chamber within each [[Lungs - Anatomy & Physiology|lung]]. | |
==Reptiles== | ==Reptiles== | ||
| − | Reptiles have a fundamentally different respiratory system to that of mammals in that they lack a bronchial tree. | + | Reptiles have a fundamentally different respiratory system to that of mammals, in that they lack a bronchial tree. |
| − | + | ||
| + | Route of Air in the Reptiliant Respiratory System: | ||
#Air enters via nares | #Air enters via nares | ||
#[[Nasal Cavity - Anatomy & Physiology|Nasal Cavity]] | #[[Nasal Cavity - Anatomy & Physiology|Nasal Cavity]] | ||
| Line 31: | Line 46: | ||
#Lungs | #Lungs | ||
| − | The lungs are paired, with respiration only | + | The lungs are paired, with respiration only occuring in the cranial region. |
| + | |||
| + | The Respiratory surface is composed of '''Faveoli''', honeycomb shaped structures which line the walls. | ||
| + | |||
| + | In addition, reptiles have a poorly developed mucocillary escalator, and rely on body positioning to clear mucous from the respiratory system. | ||
===Lizards=== | ===Lizards=== | ||
| − | + | *No diaphragm | |
| + | *Simple, saclike, paired [[Lungs - Anatomy & Physiology|lungs]]. | ||
| + | *Cranial part of lung is site of respiratory function | ||
| + | *Caudal part of lung forms air ''reservoir'' | ||
| + | *Ventilation occurs via expansion and contraction of the ribs | ||
===Snakes=== | ===Snakes=== | ||
| − | + | *Larynx projects medially from the floor of the mouth and is fused with the first few cartilage rings of the trachea. This forms a rigid '''Glottis''' which is highly mobile and can be displaced laterally to allow breathing during feeding. | |
| + | *Tongue is fixed at the rostral point of the oral cavity. | ||
| + | *Generally only the right lung is present, or at least functional - ''colubrids'' have a vestigial left lung. The lung of snakes is very fragile. | ||
| + | *Inspiration is an active process, made possible by expansion of the ribs. It occurs approx once every 30 seconds in large, healthy snakes. Expiration is a passive prcoess. | ||
| + | *Snakes have no vocal cords, but are able to make hissing noises by passing air through the glottis. | ||
| + | *Aquatic snakes have an air sacs which serves as a bouyancy aid. | ||
===Chelonians=== | ===Chelonians=== | ||
| − | Chelonians have adapted a '''dive reflex''' which enables them to respire anaerobically. They have extremely high levels of bicarbonate in their blood which allows them to buffer the lactic acid produced. Chelonians have an extremely short trachea in relation to their size. | + | *Chelonians have adapted a '''dive reflex''' which enables them to respire anaerobically. They have extremely high levels of bicarbonate in their blood which allows them to buffer the lactic acid produced. |
| − | + | *Chelonians have an extremely short trachea in relation to their size. | |
| − | + | *Have paired lungs in the '''Dorsal Cavity'''. Intestines etc lie in the '''Ventral Cavity'''. These are separated by a diaphragmatic septum which has no muscular part. | |
| − | + | *Lungs are ventilated by leg movement in terrestrial animals, and have highly developed trunk muscles to facilitate this. Aquatic species are able to respire due to the hydrostatic pressure of water, which forces air in and out of the lungs. | |
| − | |||
Revision as of 13:15, 9 September 2008
|
Fish
Fish live in a relatively dense and viscous fluid, which has little oxygen carrying capacity. In order to gain sufficient gaseous exchange for survival, fish have developed a highly efficient system which has a large surface area, and utilises energy - the gills.
Gills
Gills are in the walls of both sides of the pharynx and are composed of filaments which increase the surface area. When a fish breaths, it takes in water into the mouth, which is then forced out through the gills.
A Countercurrent Exchange system is in place within the gills to make gaseous exchange more efficient.
Amphibia
In amphibian species, the skin forms the major, and sometimes only respiratory organ.
The skin of amphibia is:
- Thin
- Poorly keratinised
- Highly vascularised
- Moist to promote diffusion of gases
Aquatic amphibians may also have internal gills and Pharyngeal Slits.
Most Amphibia also have lungs for breathing. This contains interconnecting septa which divide the lumen into Faveoli, compartments which open into a central chamber within each lung.
Reptiles
Reptiles have a fundamentally different respiratory system to that of mammals, in that they lack a bronchial tree.
Route of Air in the Reptiliant Respiratory System:
- Air enters via nares
- Nasal Cavity
- Choana
- Glottis (base of tongue)
- Trachea
- Bronchi
- Lungs
The lungs are paired, with respiration only occuring in the cranial region.
The Respiratory surface is composed of Faveoli, honeycomb shaped structures which line the walls.
In addition, reptiles have a poorly developed mucocillary escalator, and rely on body positioning to clear mucous from the respiratory system.
Lizards
- No diaphragm
- Simple, saclike, paired lungs.
- Cranial part of lung is site of respiratory function
- Caudal part of lung forms air reservoir
- Ventilation occurs via expansion and contraction of the ribs
Snakes
- Larynx projects medially from the floor of the mouth and is fused with the first few cartilage rings of the trachea. This forms a rigid Glottis which is highly mobile and can be displaced laterally to allow breathing during feeding.
- Tongue is fixed at the rostral point of the oral cavity.
- Generally only the right lung is present, or at least functional - colubrids have a vestigial left lung. The lung of snakes is very fragile.
- Inspiration is an active process, made possible by expansion of the ribs. It occurs approx once every 30 seconds in large, healthy snakes. Expiration is a passive prcoess.
- Snakes have no vocal cords, but are able to make hissing noises by passing air through the glottis.
- Aquatic snakes have an air sacs which serves as a bouyancy aid.
Chelonians
- Chelonians have adapted a dive reflex which enables them to respire anaerobically. They have extremely high levels of bicarbonate in their blood which allows them to buffer the lactic acid produced.
- Chelonians have an extremely short trachea in relation to their size.
- Have paired lungs in the Dorsal Cavity. Intestines etc lie in the Ventral Cavity. These are separated by a diaphragmatic septum which has no muscular part.
- Lungs are ventilated by leg movement in terrestrial animals, and have highly developed trunk muscles to facilitate this. Aquatic species are able to respire due to the hydrostatic pressure of water, which forces air in and out of the lungs.