Question

"Twenty different amino acids are found in the proteins of cells.

Part A
What distinguishes these molecules?
Check all that apply.
A. functional groups found in the side chains
B. the number of carbon atoms in the side chains
C. the number of carbon atoms in the core structure
D. functional groups found in the core structure"

Answer 1

Amino acids, the monomers of proteins, all share a core structure but differ in their R groups, determining their unique properties and roles in protein function. Essential amino acids must be obtained from the diet, and the variety of side chains allows for a wide range of protein structures and functions.

Step-by-step explanation:

Proteins, the complex organic compounds that play many critical roles in biological processes, are made up of amino acids. These building blocks share a common structure, featuring a central carbon atom bonded to an amino group (-NH₂), a carboxyl group (-COOH), and a hydrogen atom. The distinct characteristic of each of the 20 amino acids found in proteins is the R group or side chain, which is the variable atom or group of atoms attached to the central carbon.

The R groups range from simple structures like the single hydrogen atom in glycine to more complex rings as found in tryptophan. These side chains give each amino acid unique properties, influencing protein's structure and function. They can classify amino acids based on their polarities, such as nonpolar (hydrophobic), polar (uncharged), and often determine their role within protein structure.

Humans require a set of essential amino acids that cannot be synthesized by the body and must be obtained through diet. Phenylalanine, tyrosine, tryptophan, and other amino acids form via different side chains, offering a plethora of structures and functions to the proteins in which they are incorporated.