woahjah woahjah 23-09-2018 Biology contestada 1. what are proteins made up of ?2. what are the 4 protein structures ?3. proteins are constructed from approximately 20_______.4. a protein molecule is determined by the ________ of amino acids.5. why do vegetarians have to make sure to eat a wider variety to make sure they get all of the amino acids they need ?please help (: thank you sm