Question

please answer both the question and in you own wording with details.

6. Describe two diseases that can increase osmotic fragility. Explain why the cells are more prone to lysis. (6 marks) 7. Assuming the RBCs from this patient has no disease that affects RBC fragility, why could the MCF results from this experiment differ to those from normal RBCs? (4 marks)

Answer 1

6. Considering the two diseased for the case of osmatic fragility are Thalassemia and hyponatremia. Osmatic fragility is the degree of the proportion of hemolysis that has been taken place when the RBCs are subjected to the hypotonic solution.

Thalassemia: This disease is the inherited disorder and the body hemoglobin concentration is reduced down. This disease can result in many of the symptoms such as iron overload (The concentration of iron ions inside the body increases), Slow growth rate (Due to the anemic condition occurred due to this disease the growth of the body slows down), Infection (Due to the weakness in the body the person can face many infectious conditions), Bone deformation (In this the person's bone marrow expands because of which the bone widening starts and thus the person will face the deformed structure of the bone).

Hyponatremia: This is the disease where the sodium ion concentration in the body reduces down and thus the ability to transfer the neuronal signal drops down or became slow. The normal sodium ion concentration in the body is 135 mmol/L but in this disease, it drops down under 120 mmol/L. This situation can occur due to the release of the body fluid from the body and based on the volume of body fluid of the person weakness can be seen accordingly. If the low body fluid person is having an infection such as diarrhea it is the possible case that the body's ion balance disturbs and thus such a situation can easily occur. For the people with more body fluid needs a severe infection to undergo this disorder thus maintaining ion balance inside the body is important. It can happen that because of this disease the person's thinking ability changes and thus the ion balance plays a crucial role.

A. In the case of the thalassemia, the defected hemoglobin is inherited from the parental generation to the offspring which lead to the increase in the osmatic pressure inside the RBCs and the cell lysis is takes place because of the excess pressure which leads to the damage of the RBCs and then such condition will lead to the anemia ahead.

B. In case of the hyponatremia, the sodium ion concentration in the outer environment of the cells has been reduced down which can lead to the turbulent flow and ion imbalance across the cell and extracellular environment which leads to the cell lysis due to the effect of the osmotic fragility phenomenon.

Cells are more prone to lysis in such conditions because the cell is already undergoing such pressures such as osmotic pressures, ion balancing, etc. But, when the conditions flip out to the imbalance state the excess pressure can disrupt the cell membrane. Whenever the ion imbalance occurs across the cell membrane in the high concentration then the turbulent flow of the liquid starts entering inside the cell based on the region of ion imbalance and thus the pressure starts developing on the cell to disrupt its membrane and lead to cell lysis. For the reference the following graph explains the concept written above in the paragraph:

+ MCF Hemolysis (%) 1.0 0.9 0.8 0.7 0.3 0.2 0.1 0.0 0.6 0.5 0.4 NaCl (%)

7. The MCF for the RBCs which has been taken from the diseased patient which has not shown RBC fragility in it will differ in the MCF from the normal RBC because of the cell membrane variability for each individual and the life span of the RBCs. The RBCs which have been developed in the recent fashion will have the higher MCF and can be sustained in higher osmotic pressure while the one which has been developed earlier will not be able to sustain as long as the others. Thus the MCF for both of them will differ even though the RBC fragility has not been seen in them.

+ MCF Hemolysis (%) 1.0 0.9 0.8 0.7 0.3 0.2 0.1 0.0 0.6 0.5 0.4 NaCl (%)