Carbohydrates

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Carbohydrates:

A molecule that contains CARBON HYDROGEN & OXYGEN

Examples:

Glucose

Cellulose

Fructose

Starch

Sucrose

Glycogen

Sugars:

Monosaccharides - SINGLE

sugar units

Condensation reaction- join together to form:

Disaccharides - 2 sugar units

Polysaccharides - many chains

Monosaccharides used for ENERGY and BUILDING BLOCKS

CxH2Oy

x + y = variables

for example:

Glucose =

C6H2O6

(CH2O)n

n can be any number

If N = 3 = Triose (Glyceraldehyde)

If N = 5 - Pentose (Fructose)

If N= 6 - Hexose (Glucose)

Alpha Glucose:

Beta Glucose:

Isomerism:

Isomer = Compound with SAME chemical formula but DIFFERENT chemical structure

E.g Alpha & Beta Glucose

Testing for monosaccharides:

Benedict's Reagent

Alkaline copper sulfate solution

Heated with reducing sugar = insoluble red precipitate of copper oxide

Disaccharides:

Glycosidic Bond

Condensation Reaction:

Allow monosaccharides to make polysaccharides

- glucose + glucose = MALTOSE

- glucose + galactose = LACTOSE

- glucose + fructose = SUCROSE

Hydrolysis Reaction:

Allow polysaccharides to break apart using

water

Polysaccharides:

Formed from many Monosaccharides

STARCH:

Insoluble store of glucose in plants formed from 2 GLUCOSE POLYMERS

GLYCOGEN:

Insoluble compact store of glucose in humans

Alpha glucose units

1,4 and 1,6 glycosidic bonds

Branched structure

Amylose:

Alpha glucose

1,4 Glycosidic bonds

Spiral Structure

Amylopectin:

Alpha glucose

1,4 & 1,6 Glycosidic bonds

Branched structure

Cellulose:

Made of beta glucose

Main structural sugar in PLANTS

Structural component of cell walls

VERY strong - 33% of plant matter

Polymer of Beta Glucose:

Each monomer = inverted

Form chains - run parallel with Hyrdogen bonds between chains to form microfibrils (very strong)

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