A contusion occurs when a strong blow or repeated blows from an object struck the body, crushing the underlying muscle fibres and connective tissues without breaking the skin.
A contusion can vary in severity depending on the object and location of the injury. For example a contusion to the brain may cause a concussion that can cause serious symptoms that require immediate medical attention
On site means insitu.
invitro means in glass like a test tube.
Answer:
Permeable rock that contains and transmits groundwater is called an Aquifer.