What structures on the tongue are similar to olfactory cells

This chart lists four kinds of polymers and their sources. what can be known about all four polymers, despite their differences? they come from living things. they share ionic carbon bonds. they are at least 100 monomers long. they are made of repeating subunits.

Particles vibrate in a rigid structure and do not move relative to their neighbors.

What is a number added in front of a formula in order to balance the equation