Gas exchange Flashcards
What are the two main components of gas exchange system?
1) Specialized body surfaces area to move gas from environment to the body 2) Mechanisms that ventilate the environment side with air or water and perfuse the internal with extracellular fluid.
What are the two types of respiration?
-Internal respiration: Generate ATP -External respiration: Provides the O2 and remove CO2
What are the reason for the drop from 160mmHg to 100mmHg from the atmosphere to the lungs?
1) The airways are moist, the air from the outside become saturated with water reducing the partial pressure. 2) Fresh inspired air is mixed with a volume of air from the previous breath
What is gas solubility:
How soluble a gas is within the body.
What are the reasons why oxygen can be obtained more easily from air than from water?
1) O2 content of air is much higher than O2 in water. 2) Diffuses 8000 more rapidly in water than in the air. 3) More energy is required to move water than air because water is more dense.
What are respiratory pigments?
Molecules that binds to O2 where pO2 is high and release it where pO2 is low.
Describe the structure of hemoglobin:
Is a protein consisting of 4 polypeptide groups sorrounded by a heme group that can reversibly bind to a O2 molecule.
Describe the process of positive cooperativity:
At low pO2 values only one subunit will bind to hemoglobin and this cause the molecule to change its quaternary structure and make it easier for the other subunits to bind to oxygen.
What are the factors that alter the affinity for O2?
1) Hemoglobin chemical composition 2) pH 3) presence of 2,3 -biphosphoglyceric acid (that lowes the affinity for O2).
What are the three ways by which CO2 is transported in the blood?
1) As bicarbonate ions (70%) 2) Binded with hemoglobin (20%) 3) Carried in a solution of plasma (5%).
What is respiratory homeostasis?
Systems monitor and responds to any chanes in the partial pressure of gasses.
