Amino Acid Chains
Fewer than 50 amino acids
Peptides
What is essential and how many?
Must be consumed in the diet
– Nine essential amino acids
Amino acids are linked together to form a simple linear chain.
Primary structure
________ are macronutrients found in each cell in the
body.
Protein
_________ break apart the polypeptides to
tripeptides and dipeptides.
Proteases
2 amino acids
Dipeptides
Nonessential
– Can be synthesized in the body
– Eleven essential amino acids
Geometric shape of the protein that is folded and twisted
Secondary structure
How is a peptide bond broken?
Broken through hydrolysis
What is formed through condensation?
Peptide bond
3 amino acids
Tripeptides
Conditionally essential
Nonessential amino acids that become essential
because the body cannot make them
Three-dimensional globular shape of the protein
Tertiary structure
All _______ are made of proteins.
enzymes
Name three essential amino acids.
Histidine (His)a
Isoleucine (Ile)
Leucine (Leu)
Lysine (Lys)
Methionine (Met)
Phenylalanine (Phe)
Threonine (Thr)
Tryptophan (Trp)
Valine (Val)
More than 10 amino acids
Polypeptides
What components (two) of an amino acid is present in all amino acids?
Contains an amine group (N H2), a carboxylic acid
group (C O O H)
Two or more polypeptide chains bond together.
Quaternary structure
Excess dietary protein cannot be stored in the body.T/F
True
Name three nonessential amino acids
Alanine (Ala)
Arginine (Arg)
Asparagine (Asn)
Aspartic acid (Asp)
Cysteine (Cys)
Glutamic acid (Glu)
Glutamine (Gln)
Glycine (Gly)
Proline (Pro)
Serine (Ser)
Tyrosine (Tyr)
More than 50 amino acids
Protein
What is a peptide bond?
Form when the carbon of the acid group of one amino acid joins with the nitrogen atom of the amine group
of a second amino acid
– Formed through condensation
– Broken through hydrolysis
(unfolding) of proteins occurs in the
presence of:
– Heat
– Acids
– Bases
– Salts
– Mechanical agitation
Denaturation
What changes the function of an amino acid?
R group
Cholecystokinin stimulates the release of
proteases by the________.
pancreas