(2) Respiration Flashcards
Lungs
structure and efficiency vary amongst vertebrated
Lungs Surface area
Amphibian < Reptile < Bird < Mammal
Lungs Airflow
- Two ways in most vertebrates
- one way in birds (air sacs) = more fresh air
Gills
counter-current circulation = efficiency
Ex: fish, amphibian and arthropod larvae
Book Lungs
lung-like, but simple, book structure
Ex: spiders, scorpions
Book Gills
aquatic respiration, but simple, book structure
Ex: horshoe crabs
Tracheal
Branching tubes directly to cells
- Spiracles (opening), Tracheoles (tubes)
Ex: insects only
Cutaneous
Epithelial diffusion -> breathe through skin
Ex: Porifera, worms, amphibians to some degree
Air Flow (mammalian structure)
Nose
Pharynx
Larynx
Trachea
Paired bronchi
bronchioles
alveolar ducts
alveoli
Air Treatment (mammalian structure)
- Warmed
- Moistened
- Filtered
Inspiration Mechanism
- Ribs rise / diaphragm drops
-Chest cavity increases
-Air pressure lowered; air moves in
Boyle’s Law
As gas’s volume increases its pressure decreases and vice versa
Expiration Mechanism
- reversed
*mammalian system is “negative pressure” - frogs have a “positive pressure” system
Gas Exchange
passively (diffusion) according to O2/CO2 partial pressure
Hemoglobin Structure (Gas Transport)
- 4 globin protein subunits
- 4 Iron-containing heme groups with O2 affinity
Hemoglobin Functioning (Gas Transport)
- O2 bound at lungs (affinity high)
- O2 released at tissue (affinity low)
- Vice versa for CO2
- CO2 at tissues decreases hemoglobin affinity for O2
Myoglobin
- Oxygen carrier in muscles
-Higher )2 affinity than hemoglobin
-Releases O2 during O2 debt
Llama Hemoglobin
greater oxygen affinity than humans to counter lower O2 pressure at high elevations
Human Fetal Hemoglobin
greater oxygen affinity than adults to take )2 from mother’s blood
Total Transport Proportions
O2= 99% by hemoglobin; 1% dissolve in plasma
CO2= 23% carried by hemoglobin; 7% dissolved in plasma; 70% in RBC cytoplasm (eliminates acidity in blood)
