SBI4U - Biochemistry Macromolecules Carbohydrates & Lipids

Organic Chemistry originally the chemistry of compounds produced by living organisms in general organic compounds contain carbon and hydrogen, and usually other elements such as nitrogen, sulfur and oxygen

Electronegativity

Homework, p.18 #10 Oxygen plays a major role in biological molecules. Explain how oxygen plays a role in polarity, bond shape, (and redox reactions).

Polar vs. Non-Polar molecular polarity is determined by: –polarity of bonds within molecule –symmetry of molecular structure polarity of molecules or functional groups determines characteristics such as solubility

H-bonding

Functional Groups specific clusters of atoms attached to the carbon backbone functional groups react in characteristic ways, giving chemical properties to macromolecules, and are involved in most reactions in living organisms

Functional Groups

Macromolecules macromolecules are large molecules that are often composed of repeating sub-units some of the biologically important macromolecules are: –carbohydrates-lipids –proteins-nucleic acids

Carbohydrates carbohydrates are the most important energy source animals cannot synthesize carbohydrates; they must be consumed in plant material

Monosaccharides single sugars in straight chain or ring form C:H:O usually in 1:2:1 ratio (glucose is C 6 H 12 O 6 ) examples: fructose, galactose, ribose, deoxyribose

Monosaccharides some monosaccharides are isomers, e.g., glucose, fructose, and galactose

Disaccharides sugar molecules made from 2 single sugars formed by a dehydration synthesis (condensation) reaction See animation: D3fMaU D3fMaU

Find the sugars…

Polysaccharides oligosaccharides are shorter-chain sugars with 3-10 single sugars longer chain carbohydrates are called polysaccharides examples: starch, cellulose, glycogen, chitin

Polysaccharides

Lipids Functions: –energy storage –insulation –absorption of vitamins –raw materials

Triglycerides most common type of fat glycerol + 3 fatty acid molecules saturated and unsaturated fatty acid chains See animation: K9pnL0 K9pnL0

Trans Fats?

Phospholipids key component of cell membranes 1 glycerol + 2 fatty acid chains + 1 phosphate group phosphate end is polar and water- soluble, fatty acid end is non-polar

Phospholipids

Steroids (Sterols) carbon-based multiple-ring structure used to make hormones such as estrogen and testosterone

Waxes long-chain fatty acids linked to alcohols/carbon rings suitable as water- proof coating for plant leaves, animal feathers, etc.