Question

Osmosis and osmotic pressure play a very significant role in biological processes. The osmotic pressure of human blood is 8.21 atm at 27oC. It is interesting to know that a 0.91% (mass/volume) solution of NaCl, known as saline water is isotonic with fluids inside the human red blood cells. In this solution, the blood corpuscles neither swell nor shrink. Therefore, medicines are mixed with saline water before being injected into the veins.

Answer the following questions.

1. What is an isotonic solution?
2. How much glucose should be used per 100ml (aqueous solution) for intravenous injection that is isotonic with blood at 27° C?
3. What would be the osmotic pressure of blood if the temperature is 37°C?
4. A pure NaCl solution with salt concentration less than 0·91% (mass/volume) is hypertonic solution to human blood.
   Is this statement true or false? Give a reason.
5. Name the disease caused by taking a lot of salt or salty food, which results in water retention in tissue cells causing puffiness or swelling.

Answer 1

1. Two or more solutions exerting the same osmotic pressure are called an isotonic solution.
2. 6 grams of glucose per 100 mL of aqueous solution to make it isotonic with blood at 27°C.
3. The osmotic pressure of blood at 37°C is 8.48 atm.
4. The statement is False. It is hypotonic.
5. Edema is a disease caused by eating a lot of salt or salty food. It results in water retention in tissue cells, causing puffiness or swelling.