Gases In Blood : Carbon Dioxide

Question 1

What is the primary form in which carbon dioxide is found in plasma?

Answer 1

70% found in plasma as HCO3 (bicarbonate)

Carbon dioxide is converted into bicarbonate ions in the plasma, facilitating transport.

Question 2

What percentage of carbon dioxide is carried in red blood cells (RBCs)?

Answer 2

23% carried in RBCs (bound to haemoglobin)

Hemoglobin binds to carbon dioxide to transport it from tissues to the lungs.

Question 3

What percentage of carbon dioxide is dissolved in plasma?

Answer 3

7% dissolved in plasma

This refers to the amount of carbon dioxide that is directly soluble in the liquid portion of blood.

Question 4

Carbon dioxide diffuses into the blood from _______.

Answer 4

[respiring cells]

Respiring cells produce carbon dioxide as a byproduct of metabolism.

Question 5

How does carbon dioxide affect the acidity of blood?

Answer 5

More acid

The presence of carbon dioxide in blood can lead to an increase in hydrogen ions, lowering the pH and increasing acidity.

Question 6

What is the normal blood pH value?

Answer 6

7.35

This value indicates the acidity or alkalinity of blood.

Question 7

What gas diffuses from tissues into the blood?

Answer 7

Carbon Dioxide

CO2 is a waste product of metabolism.

Question 8

What reaction helps control blood pH?

Answer 8

Bicarbonate buffer reaction

This reaction involves the conversion of carbon dioxide and water to carbonic acid.

Question 9

What is produced when carbon dioxide combines with water?

Answer 9

Carbonic acid (H2CO3)

This reaction is crucial for maintaining blood pH.

Question 10

What happens to carbonic acid in the blood?

Answer 10

It decomposes into bicarbonate and hydrogen ions

This process is essential for regulating acidity.

Question 11

What does hydrogen do to help reduce acidity in the body?

Answer 11

It is exhaled and excreted into urine

This mechanism helps maintain acid-base balance.

Question 12

What is the role of bicarbonate in blood?

Answer 12

It buffers the acidity of blood

Bicarbonate is alkaline and helps stabilize pH.

Question 13

Fill in the blank: CO2 combines with water to produce _______.

Answer 13

Carbonic acid

This is part of the bicarbonate buffer system.

Question 14

True or False: Carbonic acid is a stable compound in the blood.

Answer 14

False

Carbonic acid is unstable and quickly decomposes.