Respiratory Physiology 5.2- Acid base balance

Question 1

What is the difference between peripheral and and central chemoreceptors responding to hydrogen ions?

Answer 1

peripheral chemoreceptors will respond to hydrogen ions that are generated by any means.
They do not have to originate from carbon dioxide.
Whereas the hydrogen ions that the central chemoreceptors are responding to always originate from carbon dioxide.

Question 2

What pathway means changes in plasma pH will alter ventilation?

Answer 2

peripheral chemoreceptor pathways

Question 3

What happens to ventilation during acidosis?

Answer 3

ventilation will be stimulated

Question 4

What happens to ventilation during alkalosis?

Answer 4

ventilation will be inhibited

Question 5

What is changing ventilation in effort for?

Answer 5

to try restore normal hydrogen ion concentration

Question 6

Describe how ventilation restores normal hydrogen ion concentration?

Answer 6

blow off more carbon dioxide and by doing this- reduce the hydrogen ion concentration (negative feedback)

Question 7

Describe what happens if we inhibit ventilation?

Answer 7

we retain carbon dioxide and therefore we drive equation to right and increase hydrogen ion concentration

Question 8

What is pH proportional to?

Answer 8

bicarbonate (kidneys and renal system) divided by carbon dioxide (lungs)
pH proportional to HCO3/ CO2

Question 9

What happens if bicarbonate decreases?

Answer 9

if bicarbonate increases, pH increases and things become more alkaline

Question 10

What happens if your carbon dioxide increases?

Answer 10

things become more acidic because pH falls

Question 11

During moderate exercise, ventilation increases in exact proportion to what?

Answer 11

metabolism

Question 12

Why does ventilation increase more than metabolism in very strenuous exercise?

Answer 12

Arterial hydrogen ion concentration increases because of increased lactic acid production.

Question 13

What involuntary stimuli can we not over ride and in what way?

Answer 13

Cannot over ride involuntary stimuli such as arterial PCO2 or [H+]
Breath-holding
Hyperventilation: Ventilation is reflexly inhibited by an increase in arterial PO2 or a decrease in arterial PCO2/[H+]

Question 14

What is the problem with breathing in alveoli?

Answer 14

Our bodies are wholly programmed to get rid of CO2. If unable to, extreme distress is experienced. In the above example breathing in CO2 increases PACO2 and thus impairs the partial pressure gradient that normally allows CO2 removal from the pulmonary artery. CO2 remains in the blood and therefore the partial pressure gradient at the periphery that pulls CO2 out of cells is also lost causing CO2 to build up in cells.