It is theoretically possible for a substance to have a negative value of cubical expansivity, which means that the substance would contract rather than expand when the temperature increases. However, it is very rare for a substance to have a negative value of cubical expansivity over a significant range of temperatures.

One example of a substance that has a negative value of cubical expansivity over a limited range of temperatures is water. Water has a positive value of cubical expansivity at...

Suicidal bag also known as lysosome is a cell organelle which are sphere shaped sacs filled with hydrolytic enzymes that have the capability to break down many types of biomolecules including the useful cells and materials that can derail the functioning of the cell . It mostly occurs in ageing, dead and diseased cells.

Lysosome is called as suicidal bag because it helps in the self-destruction of its cell, tissue or organs by releasing the lysosomal enzymes caused by rupturing of their...