Regulation Of Gas Content In Blood

Question 1

Why is it important that gas content in blood is regulated ?

Answer 1

~ensure a steady supply of oxygen to body cells for respiration
~maintain a stable blood pH so that enzyme can work properly

Question 2

What CO2 concentration are maintained in blood ?

Answer 2

~when CO2 dissolves in water, acid formed would lower the pH value of the blood and body fluid
~As enzyme works in a narrow range of pH, too much CO2 in. Blood and body fluid would lower the activities of enzyme and hence the metabolic activities in blood

Question 3

What detected the change in the blood pH ?

Answer 3

~chemoreceptor in aortic bodies in aorta

~chemoreceptors in carotid bodies in carotid arteries

Question 4

What does the chemoreceptors in respiratory centre detect ?

Answer 4

PH of the cerebrospinal fluid

Question 5

How is the basic rhythm of breathing brought about?

Answer 5

~The respiratory centre in the medulla oblongata has an intrinsic rhythmic activity that keeps breathing going automatically. ~Neurones in the respiratory centre send nerve impulses to the intercostal muscles and diaphragm muscles. The muscles contract and the lungs finally inflate. This results in inhalation.
~The neurones then stop sending nerve muscles and diaphragm muscles. The muscles relax and the lungs finally deflate. This results in exhalation. impulses to the intercostal

Question 6

How does a high carbon dioxide concentration in blood affect the rate and depth of breathing?

Answer 6

~A high carbon dioxide concentration in blood lowers the pH of blood and cerebrospinal fluid. These changes in the aortic and carotid bodies and in the respiratory centre respectively. are detected by chemoreceptors
~The receptors then stimulate the respiratory centre to send nerve impulses to the intercostal muscles and diaphragm muscles, causing them to contract faster and more strongly. The rate and depth of breathing increase