three amino acids

Amino Acid Structure:   Amino acids consist of a  carbon skeleton consisting of one carbon with three attached groups.  Carboxyl group - this in the functional group studies earlier. -(-COOH) The carboxyl group will be on one end  of the amino acid molecules and will provide the -OH group to form water during condensation   synthesis of  amino acids to form protein. Amino group - this is the functional group studied earlier. (-NH ) The amino group will be on the opposite end  of the amino acid as the carboxyl group and will provide the -H group to form water during the condensation of
synthesis of amino acids to form protein. "R" group - this group may be any of the twenty different groups of atoms which provide the protein with its characteristics. Your text will show a few of these twenty different types.  These groups vary is structure, thus  there are twenty different types of  amino acids.
        amino acids

The above figure contains the structural formula for three amino acids. Fine the amino group, carboxyl group and the "R" group. The "R" group is outlined in white. In nature their are approximately  twenty different types of amino acids based on the "R" groups. These "R"  groups produce the chemical properties of the amino acids and the proteins which they makeup.
 
17.  In your notes draw a figure showing   the general structural formula of an amino acid.
 
 

Amino acids are hooked together to forming covalent bonds between the amino acid monomers. This  is accomplished as discussed earlier by condensation synthesis. Let us review condensation synthesis:  During the process of condensation synthesis one water molecule between each monomer  will be removed. Each  monomer contributes part of the water molecule that is released; one monomer loses a hydroxyl group (OH), and the other loses a hydrogen (H).  Both monomers,  having each lost a covalent partner, now bond covalently with each other.  This time the OH is removed from  the carboxyl group of one amino acid and the H is removed from the amino group of a second acid amino acid. Trace the events  described above using the figure below.
 
 
 
18. How many water molecules will be formed when four amino acids condense to form a protein molecules?
 
 
 
 
 

In your notes using structural formulas write a reaction hooking three amino acids together during a synthesis condensation reaction.
 
Note that the bond which forms during the synthesis of two or more amino acids contains a C-N-C bond since water is cleaved between an amino group and an organic acid group. This bond is called a peptide bond. It exists only in proteins. Locate th two peptide bonds in the protein molecule below.

 
19. How many peptide bonds does a tripeptide contain?

Not only do different  protein contain different lengths of amino  acids, but the amino acids can be arranged in any order. Therefore their is almost an infinite number of proteins.

The precise sequence of amino acids in a protein is called its primary  structure.
 
20.  What is the primary structure of the following protein?

   ser-gly-gly-glut-arg-thre

21. Protein can also be hydrolyzed. If you had eggs for breakfast this morning the protein of the egg albumin (egg white) is in your large intestine. This protein is now being hydrolyzed (digested) into what products?
 
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