• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

OBJECTIVES: To determine the fragility of the erythrocyte membrane against the hemolytic effect of NaCl solutions of varying concentrations

Extracts from this document...

Introduction

PRACTICAL 4: OSMOTIC FRAGILITY OBJECTIVES: To determine the fragility of the erythrocyte membrane against the hemolytic effect of NaCl solutions of varying concentrations. INTRODUCTION: Osmosis is the diffusion of a solvent through a semi-permeable from a region of low solute concentration to a region of high solute concentration. The semi-permeable membrane is permeable to the solvent, but not to the solute, resulting in a chemical potential difference across the membrane which drives the diffusion. That is the solvent flows from the side of the membrane where the solution is weakest to the side it is strongest, until the solution on both sides of the membrane is the same strength (that is, until the chemical potential is equal on both sides). Red blood cells are bound by a membrane, which allows water to pass through while generally restricting the solutes. This process called osmosis, causes cells to shrink due to loss of water when in a hypotonic medium. This results in swelling and ultimately haemolysis as the cell bursts. The osmotic fragility test uses this fact to determine the concentration of solute inside the cell by subjecting it to the hemolytic effects of solutions of different concentrations. MATERIALS: 1. Ten test tube of NaCl (0.85%, 0.75%, 0.65%, 0.55%, 0.50%, 0.40%, 0.35%, 0.20%, 0.10% and 0%) 2. Distilled water 3. Blood 4. ...read more.

Middle

Therefore molarity of NaCl is equal to percentage of NaCl solution times 10 divide by RMM of NaCl solution. Concentration of NaCl Percentage of Haemolysis 0.15 0 0.13 2 0.11 11 0.09 14 0.08 31 0.07 79 0.06 85 0.03 92 0.02 96 0.00 100 *Graph should be Concentration of NaCl Vs Percentage of haemolysis Figure: Osmotic fragility curve (concentration of NaCl VS percentage of haemolysis) DISCUSSION: The osmotic fragility test measures the ability of red blood cells to retain their integrity in hypotonic solutions. A solution is hypotonic if its salt concentration is lower than that found in the blood, about 0.9% by weight. The test uses around 10 different hypotonic solutions varying in salinity from 0.1% to 0.9%. Each solution has a small amount of blood added to it. In a hypotonic solution, a red blood cell takes in water, lowering the salinity in the cell until it matches the salinity of the solution. This happens through the process of osmosis. Osmosis is the movement of solvent across a membrane from a lower concentration to a higher concentration. Figure: osmosis occurs on red blood cell. In this case, the solvent is water, the membrane is the membrane of the red blood cell and the concentration of salt in the solution is lower than the concentration in the cell. ...read more.

Conclusion

Recommend testing during a state of prolonged homeostasis with stable hematocrit. Figure: osmotic fragility test. Osmotic fragility of red cells increased in: 1. Hereditary spherocytosis. 2. Acquired spherocytosis. Osmotic fragility decreased in: 1. Thalassemia. 2. Iron deficiency anemia. 3. Sickle cell anaemia. QUESTION: 1. A test tube with blood in it has a particular solution added to it. After several minutes, the solution is not clear anymore, but becomes red. Which solution was added to the blood to obtain this result? 1. 0.9% saline 2. 5% saline 3. Distilled water 1. A 0.8% saline solution would be __________ to the cytosol of a cell. 1. Hypotonic 2. Hypertonic 3. Isotonic 1. If you placed a peeled apple or potato in 5% salt solution, it would: 1. Gain weight 2. Lose weight 3. Stay the same weight CONCLUSION: Osmotic fragility test is a test that measures the resistance to haemolysis of red blood cells (RBC) exposed to hypotonic solutions. RBC is exposed to a series of saline (NaCl) solutions with increasing dilution. The sooner haemolysis occurs; the greater is osmotic fragility of RBC. RBC remains same because it same as RBC concentration, Isotonic solution ? 0.9 % NaCl. RBC burst in hypotonic (< 0.9 % NaCl), and shrink (crenate) in hypertonic solutions (> 0.9 % NaCl). In hypotonic medium a membrane rupture occurs, allowing haemoglobin to exit from the cells. By measuring haemoglobin concentration, the percentage of haemolysis at different NaCl concentrations can be calculated. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our University Degree Applied Biology section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related University Degree Applied Biology essays

  1. Effect of Isotonic Exercise on HR and BP

    is greater and resistance is reduced as friction has also been reduced. This is known as vasodilation. In contrast when contraction of the smooth muscle occurs, the diameter of the blood vessel has been reduced and there is an increase in both friction and resistance. This is known as vasoconstriction.

  2. This experiment was carried out to separate and characterize the protein mixture which contained ...

    Hence the first 10 test tubes contained serum albumin instead of haemoglobin. After the addition of KCl, the haemoglobin will be released from the resin and will be collected in test tubes 11 to 20. Since haemoglobin carries positive net charge at pH6 due to protonation, the isoelectric point of

  1. Isolation &amp;amp; Characterisation of Proteins. The purpose of conducting this experiment is to ...

    in tube 11, g/100mL 3.429 x 10-3 g/100mL x 3 = 0.0103 g/100ml Mass of haemoglobin in each eluent fraction (3%) in tube 1, �g/mL Concentration of haemoglobin = 0.0103 g/100ml 100ml consists of 0.0103 g of haemoglobin, 1ml consists of = 1.029 x 10-4 g Thus, mass of haemoglobin,

  2. Food Science -Experiments to Determine the Properties and Uses of Enzymes in Food Preperation.

    consumer?s acceptability and therefore causes significant economic impact, both to food producers and to food processing industry. It is estimated that over 50% of losses in fruits occur as a result of enzymatic browning and tropical and subtropical fruits and vegetables are the most susceptible to these reactions (Queiroz, 2010).

  1. Comparing and and contrasting the endocrine system with the nervous system in their control ...

    Also behavioral mechanism will be activated such as hiding from the heat (Sun) searching for a shade or reducing the amount of clothes worn (Bradley & Calvert 2011). Fever (pyrexia) is a response to the body to fight an infection (Bradley & Calvert 2011).

  2. What Limits if any should be placed on the use of the following Biotechnologies. ...

    [5] Blackford insists that we cannot give moral weight to the interests possessed by ?entities?, which are incapable of ?suffering pain or frustration?. [5] Blackford viewpoints are immoral, and pay little attention to the potentiality of the early embryo. Even though, he is right to say that early embryos have

  1. Regional anatomy - case studies of the spinal region

    As the accessory nerve emerges from under the SCM, it is very superficial, and adjacent to cervical lymph nodes. That made the accessory nerve extremely vulnerable to the accidental injury by the needle puncturing through for the biopsy of the deep cervical lymph nodes.

  2. EFFECT OF Light wave Length on Photosynthisis

    4. Soil 5. Water 6. Light intensity sensor probes 7. Oxygen sensor probes 8. Carbon dioxide sensor probes 9. Temperature probes 10. Fluorescent light 11. Timer 12. Cellophane (green, blue and red colour) Methodology: The experiment was conducted between March 19th and March 29th 2012 at The Rockhampton Grammar School.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work