Respiration Flashcards
Composition of air- nitrogen
78%
Composition of air- oxygen
21%
Composition of air- carbon dioxide
0.04%
Partial pressure of O2 at sea level
21.2 kPa
101KPa x 0.21
Pressure equation
p = ma/A
p= 101KPa
Diffusion definition
A physical process by which ions of molecules move from a region of greater concentration to a region of lesser concentration
Fick’s law
R = D x A (p/d)
R - rate of diffusion
D- diffusion constant
A - area
p- difference in partial pressures between interior of organism and external environment
d - diffusion distance
Factors that increase diffusion
Large surface area
Small diffusion distance
High concentration gradient
What is required for gas exchange
A moist surface- O2 and CO2 must be dissolved in water to diffuse across a membrane
Value of PCO2 at sea level and high elevation
Close to 0
The respiratory medium - air
About 21% O2
Thinner at higher altitudes
Easy to ventilate
Respiratory medium - water
O2 amount much less than air (0.0015%)
O2 lower in warmer water
Harder to ventilate
What is the better respiratory medium
Air>water
8000 times better
What does the structure of the gas exchange surface depend on
Size of organism
Where it lives- water or land
Metabolic demands of the organism
Characteristics of gas exchange surfaces
Large surface area
Small diffusion distance
Moist
Favourable concentration gradient
Respiration in mollusca- snails
Snails have open circulatory system
Transport fluid is hemolymph
Hemocyanin is present in the hemolymph as the respiratory pigment that transports O2
What is the respiratory pigment in mollusca- snails
Hemocyanin
What is the transport fluid in mollusca-snails
Hemolymph
What is the respiratory protein family Planorbidae (snails and slugs)
Hemoglobin
Gas exchange in Annelida - earthworms
Takes place through the skin
May occur through gill filaments in some aquatic forms
O2 directly transported in the blood by either hemoglobin or chlorocruorin
Respiratory pigment in Annelida- earthworms
Hemoglobin or chlorocruorin
Gas exchange system of arthopoda- arachnids
Open circulatory system
O2 and CO2 carried in spider hemolymph by Hemocyanin
Respiratory organs- trachea and book lungs
Respiratory organs of Arthropoda - arachnids
Trachea
Book lungs
Respiratory pigment in arthopoda- arachnids
Hemocyanin
Gas exchange system in arthopoda- crustaceans
Gills protected by exoskeleton- feather like and attached to basal segments of the legs
Open circulatory system
Respiratory system is Hemocyanin
Respiratory medium in crustaceans
Hemocyanin
Gas exchange in insects eg locust and cockroaches
Simple tracheae with valved spiracles
Gas exchange system in insects eg mosquito larvae
Metapneustic system with only terminal spiracles
Gas exchange system in insects eg most endoparasitic larvae
Entirely closed tracheal system with cutaneous gas exchange
Gas exchange in insects eg larvae of carrion and some parasitic flies
A tracheal system with only terminal spiracles
Biological gills
Tracheated cuticular lamellar extensions from the body
Gas exchange in insects eg mayfly nymphs
Closed tracheal system with abdominal tracheal gills