<span>The Excretory System</span>
<span>R group (or side chain) is an organic component of amino acids that is unique to each amino acid. </span> <span>Three of the amino acids have basic side chains at neutral pH: arginine (Arg), lysine (Lys), and histidine (His). Their side chains contain nitrogen and resemble ammonia, which is a base and their pKa's are high enough that they tend to bind protons, (positive charge). Aspartic acid or aspartate (Asp) and glutamic acid or glutamate (Glu) are acidic amino acids because their side chains have carboxylic acid groups whose pKa's are low enough to lose protons, (negatively charged). The non-polar amino acids contain uncharged functional groups<span> at physiological pH and are incapable of participating in hydrogen bonding. </span></span>
There’s a lot but probably you know the basics like they’re vertebrates which means they got back bones , they have a scaly skin , they reproduce shelled eggs , cold blooded
The elements in each group have the same number of electrons in the outer orbital
They are formed primarily on the cell's Ribosomes.