Chapter 19.4 Gas Exchange and Transport-Respiratory System Flashcards
What do gas molecules behave due to Dalton’s law?
Undergo continuous random motion
Collide with each other: pressure
closer together more pressure
What happens if there is anything that increases movement of molecules?
it also increases pressure: for example, temperature
What is pressure directly proportional to?
directly proportional to temperature
What is Dalton’s law?
In mixture of gases, pressure exerted by each gas is independent of other gases
What is total pressure equal to?
equal to sum of partial pressures
When will molecules of gas will dissolve in liquid?
When liquid (blood) is exposed to air containing gas(oxygen)
What is Henry’s law?
partial pressure of oxygen in air (21%) is proportional to amount dissolved in blood
What happens If we breathe higher concentration of oxygen
More will dissolve into blood
In reverse, what happens if partial pressure is higher in blood
CO2 will diffuse out of blood into gas phase
What is Diffusion?
movement of molecules from higher to lower concentration
What is Hyperventilation?
increased breathing rate
What is Hypocapnia caused by hyperventilation?
low CO2
What is Respiratory alkalosis caused by hyperventilation?
high blood pH
What are symptoms when there is hyperventilation?
dizziness, tingling in fingers, toes, and face, and weakness, and may cause fainting
What is Hypoventilation?
decreased breathing rate
What is Hypercapnia caused by hypoventilation?
high CO2
What is Respiratory acidosis caused by hypoventilation?
low blood pH
What can cause hypoventilation and what happens?
Certain drugs, alcohol, stroke or tumour affecting brainstem, or altitude sickness can cause hypoventilation and can be life threatening
What are three ways that carbon dioxide is transported and what percentage of them?
Dissolved in plasma – 10%
Carbaminohemoglobin – 25%
Bicarbonate ions – 65%
How much blood PH vary?
Blood pH does not vary much
Arterial pH – 7.4
Venous pH – 7.36
What does Carbonic anhydrase in red blood cells catalyzes and what would be formula?
Catalyzes formation of carbonic acid H2CO3
CO2 + H20 → H2CO3
What is formula when carbonic acid dissociates:
H2CO3 → HCO3- + H+
What would be complete formula of carbon dioxide transport?
CO2 + H20 → H2CO3→ HCO3- + H+
Where does Bicarbonate (HCO3) enter when it leaves red blood cells
Enters plasma – pH drops / more acidic
