Changes

[[Image:Doglunginflated.jpg|right|thumb|200px|©RVC 2008]]

[[Image:Doglunginflated.jpg|right|thumb|200px|©RVC 2008]]

[[Image:Routeofairthroughrespiratorysystem.jpg|right|thumb|200px|'''Schematic Diagram showing the route air takes through the respiratory system''']]

[[Image:Routeofairthroughrespiratorysystem.jpg|right|thumb|200px|'''Schematic Diagram showing the route air takes through the respiratory system''']]

The lungs are the site for [[Gas Exchange - Anatomy & Physiology|gaseous exchange]], and are situated within the thoracic cavity. They occupy approximatley 5% of the body volume in mammals when relaxed, but generally have no fixed size or shape since their volume is constantly changing with the processes of [[Ventilation - Anatomy & Physiology#Inspiration|inspiration]] and [[Ventilation - Anatomy & Physiology#Expiration|expiration]].

The lungs are the site for [[Gas Exchange - Anatomy & Physiology|gaseous exchange]], and are situated within the thoracic cavity. They occupy approximately 5% of the body volume in mammals when relaxed, and their elastic nature allows them to expand and contract with the processes of [[Ventilation - Anatomy & Physiology#Inspiration|inspiration]] and [[Ventilation - Anatomy & Physiology#Expiration|expiration]].

The lungs, along with the [[Larynx - Anatomy & Physiology|larynx]] and [[Trachea - Anatomy & Physiology|trachea]], develop from a ventral respiratory tract. After separation from the developing [[Oesophagus - Anatomy & Physiology|oesophagus]], two lung buds develop, which undergo divisions as they grow, forming the beginnings of the [[Bronchi and bronchioles - Anatomy & Physiology|bronchial]] tree. This process is not completed by [[Parturition - Normal Parturition - Anatomy & Physiology|parturition]].

The lungs, along with the [[Larynx - Anatomy & Physiology|larynx]] and [[Trachea - Anatomy & Physiology|trachea]], develop from a ventral respiratory tract. After separation from the developing [[Oesophagus - Anatomy & Physiology|oesophagus]], two lung buds develop, which undergo divisions as they grow, forming the beginnings of the [[Bronchi and bronchioles - Anatomy & Physiology|bronchial]] tree. This process is not completed at the time of [[Parturition - Normal Parturition - Anatomy & Physiology|parturition]].

==Structure==

==Structure==

==Species Differences==

==Species Differences==

* Externally the lungs of the '''Horse''' show almost no lobation. Internally the right lung of the horse lacks a Middle Lobe.

* The lungs of the '''Horse''' show almost no lobation, and the right lung of the horse lacks a Middle Lobe.

*The lungs of '''Ruminants''' and '''Pigs''' are obviously lobed.

*The lungs of '''Ruminants''' and '''Pigs''' are obviously lobed.

*The fissures between lobes (''Interlobar fissures'') are deeper in the dog and cat lung compared to other species.

*The fissures between lobes (''Interlobar fissures'') are deeper in the dog and cat lung compared to other species.