1.D 2.A that is pretty hard
They can be joined through a Peptide bond
The amino acids serve as the foundation for proteins. Water is produced when the amino acids are linked to form a lengthy chain of acids via amino and carboxyl. The main protein is made up of these long chain amino acids.
When the carboxyl group of one molecule combines with the amino group of the other molecule, a molecule of water is released, and a peptide bond is created between the two molecules (H2O). This condensation event, sometimes referred to as a dehydration synthesis reaction, typically takes place between amino acids.
<h3>What is a Peptide bond ?</h3>
The carboxyl group of one amino acid is joined to the amino group of another to produce a peptide bond, also known as a eupeptide bond. In essence, a peptide link is an amide-type covalent chemical bond.
Learn more about Peptide bond here:
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Well red blood cells carry oxygen to muscles
Circulatory system is probably the answer you are looking for.
