Download Amino acids

Chemistry of Life
Biology – S1
Video: http://viewpure.com/2Jgb_DpaQhM
• Proteins
• most diverse of all biological molecules
• made by bonding amino acids together is specific orders
• Amino acids
• monomers (building blocks) of proteins
• over 500 different AA are known
• 20 AA are standard and make many different kinds of proteins
• 9 are considered essential (must get from the diet) our body can’t make them
• the shape determines the function of the protein
*Failure to obtain enough of even 1 of
the 10 essential amino acids, those
that we cannot make, results in
degradation of the body's proteins—
muscle and so forth—to obtain the one
amino acid that is needed. Unlike fat
and starch, the human body does not
store excess amino acids for later use—
the amino acids must be in the food
every day.
7 Classes of Proteins
1. Enzymes: help speed up chemical
reactions (catalyst) without itself
being changed (LOCK and KEY)
• active site where substrate
attaches
Examples in our bodies
• protease- breaks down proteins in
meat, nuts, eggs,cheese
• pepsin- breaks down proteins to
peptides
• peptidase- breaks down peptides to
amino acids
Enzymes/catalyst
animation
2. Structural: build feathers, bones, cartilage, webs
Keratin- makes up hair and nails
•Collagen- makes up bone
and cartilage
3. Transport: move molecules
across cell membranes,
• hemoglobin-moves oxygen
to our body
• insulin- controls glucose
metabolism
4. contractile: provide muscular movement (actin
and myosin- slide filament theory of
contractions)
5. storage- (egg white) source of AA for embryo
6. defensive- antibodies, blood clotting
7. signal- hormones
Denaturation- polypeptide chains unravel and lose their
shape and function (frying an egg) clear proteins are
denatured and they get white (useless)