Biological Molecules (Carbohydrates)

Polysaccharide (Starch & Cellulose)

Structure

Helical shape (α) and straight chain shape (β), function grp. hydroxyl carbonyl groups, many monosaccharides bonded together

Monomer

Composed of glucose monomers joined in α 1,4 linkages

Linkage

Many alpha and beta glycosidic linkage formed by condensation reaction

Properties

- White solid - Polar - Solid and liquid - Insoluble in water - Not sweet in taste - hydrophobic

Functions

Stored energy, not immediate since many bonds need to be broken, important for cellular structure (cell wall)

Oligosaccharide (Maltotriose)

Structure

Made up of to 20 monosaccharides joined together, function grp. hydroxyl carbonyl groups, chain of many monosaccharides

Monomer

Three glucose molecules bonded together

Linkage

Glycosidic bonds formed by condensation reaction

Properties

- Polar - Solid and liquid - Soluble in water and acids, not in nonpolar solvents - Sweet

Functions

Found on the plasma membrane of animal cells for cell-cell recognition and cell binding, different oligosaccharide determine blood type of red blood cells,

Monosaccharide (Glucose & Galactose)

Structure

Molecules of C, O, H, function grp. consists of hydroxyl carbonyl groups, ring structure and α-carbohydrates the OH grp. is opposite direction of monomer (CH2OH), β-carbohydrates are same direction of monomer, helical or straight chained shape

Monomer

Monomers include glucose, fructose and galactose

Linkage

When bonded more than one monosaccharide, glycosidic bonds are formed using condensation reaction, water is removed for bonding capability

Properties

- Colourless - Polar - Solid and liquid - Soluble in water and acids, not in nonpolar solvents - Sweet in taste

Functions

Immediate source of energy, important for structure of organisms and cellular respiration, create energy for cells

Disaccharide (Lactose)

Structure

Two carbon rings bonded, consisting of of C, O, H, function grp. hydroxyl carbonyl groups, two sugars bonded together

Monomer

Glucose and galactose make up this disaccharide

Linkage

Galactose and glucose units joined by a β-1,4-glycosidic linkage, by a condensation reaction

Properties

- White solid - Polar - Soluble in water and ethanol

Functions

Lactose is composed of glucose and galactose, two simpler sugars used as energy more readily available, it aids in the absorption of calcium and phosphorus in our bodies