What is the role of bicarbonate ion in control of pH in blood ? Explain?

Question

What is the role of bicarbonate ion in control of pH in blood ? Explain?

Answer 1

it's a 'buffer'. basically think of the buffers in bowling alleys- the bars on the side that help keep your bowling ball stay on track. same thing with the bicarbonate- it plays a significant role in keeping your blood at a healthy pH. otherwise if your pH was free to do whatever it liked you'd be in trouble.

Answer 2

It's pretty obvious that bicarbonate ion is involved in the buffer system that keeps the pH of your blood around 7.4.  Here's how.

Some carbon dioxide that is produced in the body is not expelled but stays dissolved in your blood.  The CO2 reacts with water to establish a buffer system consisting of the equilibrium with H+ and HCO3-.  This the buffer system.

CO2 + H2O <==> H+ + HCO3-

For instance, if acid (lactic) builds up in the blood the equilibrium system will shift to the left to use up the H+.

By the way.  You will notice that I didn't include "carbonic acid", H2CO3 in this equilibrium.  That's because it doesn't exist as an undissociated molecule in aqueous solutions.  What we call carbonic acid is actually the equilibrium that I've indicated above.

Answer 3

It acts as a buffer to keep the pH constant by changing between carbonic acid and the bicarbonate ion