A person suffering from high blood PRESSURE is advised not to take large amounts of salt, this is because the blood contains RBC cells and if we take more amounts of salt then there might be chances that we might end up vomiting. This is due to reverse peristalsis or exosmosis. There is high content of salt in the BODY when compared to the RBC cells in the blood. So the salt causes the cell or RBC to shrink and the contents inside the cell would cause one to throw up. The person would IMMEDIATELY fall sick and may be dehydrated for a long time if it continues.
The RBC would swell up because there is a higher concentration of the solution outside the cell when compared with the solution concentration inside the RBC. So osmosis takes place where water or any solution PASSES from a region of higher concentration to a region of lower concentration. The RBC would swell up and would burst because it does not have a cell wall that can counter push the contents inside the cell.
Dried up fruits and vegetables return back to their original state when they are kept in water. This is because the fruits or vegetables are dried up or dehydrated (removing water), so the water concentration is less inside the FRUIT than compared with the water concentration outside the fruits. This process is known as osmosis