In a watery environment polar amino acids want to have contact with

Polar amino acids tend to be hydrophilic, meaning that they bond to water. These are those that establish hydrogen bonds to water. They are considered polar because they have a R group that's hydrophilic. Because of this characteristic, in a protein they tend to a be a at the surface maintaining contact with the surrounding solutions. The most common polar amino acids are: arginine, lysine, glutamic acid, and aspartic acid.

Size and shape of continents

They are both used to view parts of the cell