Question

you took a fresh tomata and put it in a highly concentrated salt solution for 2houres. your little brother looked at it and stated"the fat tomota is so thin now" what is magic? (a)define the phenomenon which his taken place.(b)how does a cell wall help a plant to withstand hypotonic external media without bursting

Answer 1

a. Inthe above change, osmosis was taken place... Osmosis is nothing but moving from high concerntration to low concerntration by any liquid... so here the water inside has low concerntration where as salt water is high concerntration. so the tomato lots its water quantity and became thin.
b. cell wall which is very tough, porus, it applies such type of pressure on the cell and protects it from external environment. thus the cell avoids from brusting as the cell wall does not allow everything to come inside the cell. It selects the material very selectively. Thus the cell wall protects the cell from brusting.