does the contractile vacuole of a paramecium work more when

does the contractile vacuole of a paramecium work more when it is swimming in a hypotonic, isotonic, hypertonic environment? How do oral rehydration salts help to rehydrate people with severe diarrhea such as cholera?

Solution

Answer

1. The basic function of a contractile vacuole in paramecium is osmoregulation. The contractile vacuole is filled by radiating canals and collects fluid from the cytosol, after bring filled, it fuses with the plasma membrane and expels its content.

First defining the conditions: In an isotonic solution, the concentration of solutes inside the paramecium is equivalent to the concentration of the solutes in the solution. Hence contracticle vacuole mediated osmoregulation is not required.

In hypotonic solution: The concentration of solutes in the solution is lesser than the concentration of solutes inside the paramecium. the water/solvent will gush inside the plasma membrane and hence contractile vacuole work at their full potential in such condition.

In a hypertonic solution: In hypertonic solution: The concentration of solutes in the solution is greater than the concentration of solutes inside the paramecium. The water/solvent will gush outside the plasma membrane and the cell shrinks.

The contracticle vacuole works the most in case of hypotonic solution.

2) In case of diarrhea, which usually cures itself in 3-5 days, but diarrhea in case of cholera, causes extreme loss of nutrients and salts along with the watery stools passed. The oral rehydration salts and glucose contained in the ORS enables the intestines to absorb fluids and salts effeciently. ORT alone by itself is an effective treatment for around 95% of patients suffering from acute watery diarrhoea, regardless of cause, and prevents unnecessary drip therapy in most but the most severe cases.