Osmotic Fragility Test

Question 1

Apppartus used

Answer 1

Test tubes

Question 2

Clinical importance

Answer 2

Diagnosis of hereditary spherocytosis most common type of hemolytic anemia

Question 3

Materials used

Answer 3

5 ml of different nacl concentrations in first 7 test tubes
5 ml of distilled water in 8th test tube
1 ml of blood used added in tube

Question 4

Experiment Steps

Answer 4

Don’t shake tube and leave tubes for 30 minutes then observe hemolysis

Question 5

Test results

Answer 5

Nacl 0.9% solution is isotonic solution
Hemolysis start at 0.5% nacl solution
Hemolysis end at 0.3% nacl solution
Distilled water show complete hemolysis

Question 6

Different colors

Answer 6

At 0.9% the rbcs settle down and clear
At 0.5% solution where hemolysis start some rbcs remain unruptured and settled down with some pink color
At 0.3% all rbcs rupture so all tube is tinged red in color
Distilled water show same results and uniform color
More than 0.9% nacl shrinkage of rbcs

Question 7

Test principles

Answer 7

Rbcs remain unruptured in normal saline solutions
Ability to resist hemolysis is decreased due to increasing hypotonic solutions

Question 8

Hereditary spherocytosis

Answer 8

Hemolysis start at 0.7% nacl solution
Hemolysis end at 0.5% nacl solution

Question 9

Osmosis definition

Answer 9

Movement of water from high water potential to low leather potential down water potential gradient through a partially permeable membrane

Question 10

Osmotic pressure

Answer 10

Pressure needed to stop osmosis