JAMB Biology 2002 Question 34

Question 34

Cell and Its Environment

When a marine fish was taken from the ocean and put in a tank of fresh water, it died after a short period because

  1. A.the tank was too small compared to the large ocean
  2. B.the body cells of the fish swelled and burst as a result of the hypotonic fresh water
  3. C.the body cells of the fish shrank as their sap was hypertonic to the fresh water
  4. D.there was no food in the tank, so the fish starved.
Show the answer and explanation

Answer: B (the body cells of the fish swelled and burst as a result of the hypotonic fresh water)

Explanation

Fresh water is hypotonic (more dilute) compared with the fish's body fluids. Water enters the cells by osmosis until they swell and burst.