PG. 19 – 29(SAME PAGES FOR THE NEXT FEW
CLASSES)
Protein(polypeptides, enzymes)
Building proteins
Proteins are polymers of amino acids
There are ~21 standard (natural) amino acids 9 are essential 12 are non-essential
What does this mean?
The vegan dilemma…
Animal foods contain all essential amino acids(Plant-derived foods do not)
Protein structure
Proteins vary enormously in size Smallest protein = 20 amino acids Large protein – 27,000 amino acids
The order of the amino acids determines the structure, properties and function of the protein
peptide bond
Protein structure
There are 4 levels of protein structure1. Primary structure
amino acid sequence
2. Secondary structure simple 3D arrangements
Alpha helix
Beta sheet
Protein structure
3. Tertiary structure 3D protein structure
4. Quaternary structure multiple proteins combined to make 1 functional unit
Protein function
Proteins can serve multiple functions1. Structural proteins
Muscle, bone, hair skin
2. Hormones Testosterone, estrogen, insulin
3. Enzymes “Big molecules that do stuff”
(eg. accomplish or aid in most cellular reactions)
Denaturation
The shape of a protein can be altered by heat or radiation
This denaturation causes the protein to unfold/uncoil and lose functionality
This change is usually permanent
Denaturation
Testing for proteins
Biuret solution Turquois solution becomes violet
Try this…
Pg. 27 #22 – 24