Download Tracheal System

Gas Exchange
Chapter 42
Pages 915-927
Objectives:
 Describe gas exchange through gills, the tracheal systems and lungs, give an example of an
organism that uses each.
 Define unidirectional, bidirectional and cutaneous respiration.
 Compare and contrast the respiration of mammals and birds.
 What is the difference between negative and positive breathing?
 Why is air a better respiratory media than water?
 Explain why insects don’t need blood.
Function:
 The respiratory system is responsible for
o Bringing ___________________________ for use in _______________________
o Expiring ___________________________ created in
__________________________________________
Simple Diffusion:
 _________ moves into organism from the _________________
 Sufficient only for ____________________________________
 What must be true of oxygen concentrations on the inside of the
body versus the concentration of oxygen in the water?
In the animal, where must the lowest oxygen concentrations be found?
Diffusion
 In all animals, respiration eventually comes down to ___________________________
 Oxygen moves from ___________________________________ in the ______________
to __________________________ in the __________________ (partial pressure)
 Like circulation, diffusion must take place across a ___________________ membrane
with large ______________________________________
 In respiratory systems, these are called _______________________________________
 Examples of respiratory surfaces include:
 A hypothetical endothermic (warm-blooded) animal and an equally sized ectothermic (coldblooded) animal exist in a similar environment. Which will have a larger respiratory surface
and why?
Simple Diffusion “Plus”
 “Plus”
o System that obtains oxygen by creating a _______________________________
necessary for ____________________________________________________
 Partial Pressure Creating Systems + Diffusion
o __________________
o __________________
o Lungs
Respiratory Media
 Respiratory Media is what the ____________ is in (water or air)
 _______________ is the superior respiratory media!
o Air has 40 times more ____________________ per liter than water
 The warmer and saltier the water, the __________ the oxygen content
o Water is more ________________ than air
o Water is ____________ than air
 In terms of energy, what does this mean for aquatic animals?
Vertebrates
 _________________
 Bidirectional
 _________________
Unidirectional
 Unidirectional: Carbon dioxide and oxygen move in ____
______________________________________________
 Example: _______
Bidirectional
 Bidirectional: Oxygen and carbon dioxide move in ________________
____________________________
 Example: __________________
Cutaneous
 Cutaneous: Oxygen and carbon dioxide are
exchanged through ___________________
 Skin must be ____________!!!
 Ex. _________ (have very primitive lungs, so the
majority of respiration is
cutaneous)
Gills
 Gills: ________________ of the body surface that are
__________________________________________
o How do gills improve respiration?
 Ventilation
o Movement of __________________ over the
_______________________
o Maintains the _____________________ necessary
____________________
for
 Ventilation is promoted by ______________________________
_____________________(swimming) or ___________________
____________________ (lobster use paddle-like appendages to create a
______________________________ over their gills)
 Concurrent Exchange: the passing of a ________________ between two
______________ flowing in ___________________________________
o What are the two fluids?
o What is the substance?
 Why aren’t gills found on land animals?
Tracheal System
 Tracheal System: air tubes that branch __________________________
o _________________ respiratory system
o ____________________ respiratory system of ____________ animals
 Components
o Spiracle: allows oxygen into the ________
o Trachea: __________________________
o ___________: Smaller branches for gas
exchange
 Due to the small size, __________ does not need
__________ to transport
oxygen
Lungs
 Lungs: ______________ respiratory organs
o Subdivided into _________________
o Must be in contact with ___________
______________
o ______ and __________ of lungs
increase with ________________
 Examples: _________________________




Trachea: Tube from _________ to ____________
Bronchi: __________ from the __________, one to each lung
Bronchioles: _____________ and ________, ___________ tubes
Alveoli: ________________
o Clustered at the end of the __________________
o ________________________________________
Ventilation of Lungs
 __________________ Pressure Breathing
o _________________ (like a balloon) with forced air
o Seen in frogs
 When a frog puffs up, he is taking several
inhalations without exhaling
 __________________ Pressure Breathing
o ___________ air into the lungs by ________________ the thoracic
cavity via the ______________
o Remember _________________ Law
 As _______________ increases, ______________ decreases
 On ______________ the pressure decreases, gas
____________ to equalize the pressure
 As volume ____________, pressure _____________
 On ______________ pressure increases, pushing gas out
to equalize pressure with ____________ environment
 Birds: extremely efficient and complex
o What adaptive pressures acted on birds to develop a more complex
respiratory system?
 ____ inhalations, ____ exhalations
o Allows for _________________________