Why are metamorphic rocks formed by contact metamorphism usually not dense or resistant?

Hahaha good one. you ? & oop

Well,what i learned was that unlike many other  endothermic  reactions,  photosynthesis  does not absorb energy as heat. instead, during plants absorb energy from sunlight to turn carbon dioxide and water into oxygen and glucose, which is a type of sugar molecule. the energy is stored in the glucose molecules, ready to be used when needed. 

The mesophyll chloroplast and thylakoids