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Monosaccharide = simple sugar

(CH2O)N, so if N= 3, = C3H6O3

3 = triose, 5 = pentose, 6 = hexose

disaccharide = two monosaccharides join together

When this happens its a condensation reaction so water removed [Gluc + Gluc = maltose] This isenzymed and reversible

Disaccharide formula = [C6H10O5]n

Other Disaccharides: -Sucrose [a-gluc + fruc], -Galactose [lac + fruc]

All mono saccharids and some disaccharides are reducing sugars. Reducton is gain of electrons,so reducing sugars donate electrons to other subtances.

Benedict's Test: Add 2cm^3 of Benedict's solution + food sample to test tube. Heat gently boilingtube for 5 minutes. Solution will appear GREEN ORANGE OR RED depending on how much

reduc. sugar is present. [Due to Cu2+ being reduced to Cu+ which forms Cu+O = red]

18% of biomass in humans is composed of proteins

Keratin in hair/nails

Collagen in connective tissue

They're involved in body functions:

enzymez

hormones

antibodies

haemoglobin

Contain C,H,O + N

All proteins are polymers of amino acid

20 diff. amino acids. Single protein can contain 1000s of monomers in any order so no of diffproteins is very big.

Each diff amino acid has a diff R group.

Amino acids join by condensation like carbohydrates to form a DI-PEPTIDE. Water is formed asalways. Peptide bond formed.

Polypeptide = chain of amino acids joined by peptide bonds.

1ary structure - sequence of amino acids2ndary structure - 3D folding of the primary structure. Most common forms are Helises + B-Platedsheets3iary structure - 3D folding of secondary structure. ALL regulatory proteins [eg enzymes] havecomplex tertiary structures. Different R-Groups may attract or repel each other and so primarystructure determines 3iary structure. 3iary structure held by H-bond between R groups, ionic andcovalent bonds, electric repulsion and DISULPHIDE Bridges.

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4nary structure - This describes the arrangement of two or more polypeptides in proteinsconsisting of more than one.

Fibrous = little or no tertiary structure + consist of long parralel polypeptide chains twisted into A-helises. There may be H- bonds between these chains, and this makes these proteins very toughand insoluble. They are used mainly for STRUCTURAL purposes. EG Keratin in hair, Collagen inconnective tissue.

Globular = complex 3ary + 4nary structure + are folded into SPHERICAL shapes thereforeGLOBULAR. Like enzymes + antibodies.

TEST FOR PROTEINS - Biuret test that detects peptide bonds - Place sample of soution to betested in a test tube and add an equal volume of NaOH [sodium hydroxide]. Add few drops ofCopper [II] Sulphate and mix gently. Purple = PROTEIN!