Video Transcript
There are 20 different amino acids
in humans that share a similar basic structure. Which group differs between all
amino acids?
This question is asking us about
amino acids in humans, so let’s discuss the basic structure and function of amino
acids to answer this question. Humans have 20 different amino
acids that are the building blocks to make up all the proteins in the body.
Each of these amino acids contains
the same basic structure, so let’s look at the individual parts. In the center is the central
carbon, which bonds to four different chemical structures. The first is a carboxyl group, then
a hydrogen, an amino group, and an R group, sometimes called the side chain. The R group is the component of an
amino acid that differs between all amino acids. Some R groups are relatively simple
like glycine, which contains a hydrogen for its R group, while some are more complex
like lysine, which has a hydrocarbon chain that terminates with a charged amino
group.
The difference in R groups is what
contributes to the complex interactions among amino acids, which causes specific
folding of the polypeptide. Now that we’ve reviewed the
structure and function of amino acids, we are able to answer our question
correctly. The group that differs between all
amino acids is the R group.
