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An experiment was carried out to investigate haemolysis of human red blood cells. The red blood cells were placed in different concentration of sodium chloride...

An experiment was carried out to investigate haemolysis of human red blood cells. The red blood cells were placed in different concentration of sodium chloride solution. The percentage of haemolysed cells was determined. The results were as shown in the table below.
52420191623.png
a) i) On the grid provided, plot a graph of haemolysed red blood cells against salt concentration.
ii)At what concentration of salt solution was the proportion of haemolysed cell equal to non-haemolysed cells?
iii) State the percentage of cells haemolysed at salt concentration of 0.45%.
b) Account for the results obtained at:
i) 0.33 percent salt concentration.
ii) 0.48 per cent salt concentration.
c) What would happen to the red blood cells if they were placed in 0.50 percent salt solution?
d) Explain what would happen to onion epidermal cells if they were placed in distilled water.

Answers

sharon
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ii) 0.403 ±0.002 ;
iii) 10±1%;
b) i) 0.33 percent salt concentration - Less concentration/dilute/hypotonic than blood cells cytoplasm; water is drawn in by
osmosis; the cell swell and eventually burst( a process called haemolysis);.
ii) 0.48 percent salt concentration - concentration of red blood cells cytoplasm is same as concentration of salt solution
(isotonic) therefore no net movement of water by osmosis; hence cells remained normal and none were haemolysed.;
c) 0.50% salt concentration is highly concentrated solution/hypertonic than blood cells cytoplasm; red blood cells would loose
water by osmosis; shrink and become creanated.
d) The cell sap is more concentrated than surrounding; water enters into the cell by osmosis; the cell swells/become turgid; but
does not burst due to the rigid cellulose cell wall;.
sharon kalunda answered the question on May 24, 2019 at 13:27

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