Question

if vegetables such as brinjals and lady's fingers become somewhat dry and shrivelled, they are put in water. they start looking fresh again, because water enters inside them. In the absence of any opening how does water enters the vegetables

Answer 1

In a normal scenario, there are small opening presents on the wall which transports water and other material in and out of a cell.  

In the absence of any opening, the water will enter the plant through cell wall. The spaces between the cell wall allow the transportation of water inside the cell.

Answer 2

When dry brinjals and lady's fingers become somewhat dry and shrivelled, they are put in water and eventually they start looking fresh again.

Water enters them by the process of osmosis.

The vegetables have a higher concentration of solute so when they are placed in water, water flows from a region of their higher concentration to a region of their lower concentration resulting in the swelling of the vegetables.