1.10.4.2. Proteins are the Major Components of Living Organism

• amino acids are the building blocks of proteins
• growth and repair
• build body parts
• provide energy
• carry oxygen in blood
• fight germs
• make hormones
• Enzymes: special type of protein that regulates chemical activities in the body.
• There is an "N" in the word proteiN.  The element nitrogen is always present in proteiNs.

• By what process are individual amino acids combined to from larger proteiNs? It is the dehydration synthesis. This is the process by which any small organic molecules are combined to form big organic molecules. The dehydration synthesis of a protein is typically illustrated as:

• Dipeptide is just a bonding between two amino acids. If we continued to add more and more amino acids to the dipeptide we would then call the molecule a Polypeptide and then we would end up with large protein molecules.
• Dipeptide, polypeptide, peptide bonds are all protein stuff.
• The hydrolysis (breakdown) of a dipeptide/polypeptide can be summarized as:

Dipeptide/Polypeptide + Water → Amino acids + Amino acids

• On hydrolysis, water is added at the beginning and the products are smaller than the molecule we start with.