biomolecules

qtr 3, periodicals

carbohydrates

• most abundant & least expensive sources of energy in food

• molecules from aldehydes & ketones containing numerous hydroxyl group

• water-soluble macromolecule

monossacharide

contains 1 sugar unit

dissacharides

contains 2 sugar units

oligossacharide

contains 2-10 sugar units

polyssacharide

contains 10+ sugar units

glycosidic bonds

• happens through condensation reaction wherein water becomes a by-product

• forms dissacharides, oligossacharides, & polyssacharides

glycogen

created & stored when the carbohydrates are not used to produce energy in the metabolism

lipids

• main elements = carbon/hydrogen/oxygen

• sources = fats/cell membrane/waxes/steroids

• function = energy storage/cell protection/protective coating/component of hormone

fatty acids

• consist of a hydrophobic tail & a hydrophilic head

• natural — may be saturated or unsaturated

saturated fatty acids

• no carbon double bonds

• have higher melting points

• lauric acid — saturated fatty acid found in coconut oil

unsaturated fatty acids

• 1 or more double bonds in the hydrocarbon chain

• lower melting point

• oleic acid — unsaturated fatty acid found in animal fat

steroids

• simple lipids w/ a backbone structure consisting of 4 fused carbon rings

• cholesterol — most abundant in animal tissues, composed of a backbone structure w/ a hydroxyl group

triglycerides

• most abundant class of lipids in plants & animals, stored forms of energy

• produced through esterification of 3 fatty acids to a single glycerol molecule

esterification

• reaction between an alcohol & a carboxylic acid

• results in the formation of an ester & water

fats

solid triglycerides of animal origin

oils

liquid triglycerides of plant origin

phospholipids

• glycerol, phosphate, a simple organic molecule, & 2 fatty acids

• building blocks of cellular membranes

• have hydrophilic head & hydrophobic tail

• holds cells together & controls the substances that pass into/out of the cells

lecithin

phospholipid that is a major component of cell membrane & an emulsifying agent

cephalin

phospholipid found in most cell membranes, particularly in nervous tissues & blood platelets

waxes

• water-insoluble, low-melting solids

• long-chain fatty acid & long-chain monohydroxy alcohol

natural waxes

• often mixtures of esters of fatty acids & may contain hydrocarbons

• mainly function as a protective layer in plants & animals

proteins

• elements = carbon/hydrogen/oxygen/nitrogen & sometimes sulfur

• sources = milk, meat, nuts, egg, enzymes, tofu, vegetables

• function = repair tissues, speeds up process, signalling hormones, storage

enzymes

speeds up biological processes

collagen & keratin

structural proteins

• strengthens skin/bones/hair

insulin

signalling proteins

• signals the body to store blood sugar

hemoglobin

transporting proteins

• oxygen throughout the body

casein

storage proteins

• stores all the nutrients babies need to grow

fibrinogen

protection

• antibodies to counteract foreign substances that can cause diseases

• protein that facilitates blood clotting

myosin & actin

movement

• muscle contraction/relaxation

• protein molecules in the muscles

nucleic acids

• elements = carbon/hydrogen/oxygen/nitrogen/phosphorus

• sources = rna/dna

• function = carries genetic material of an organism

• macromolecules that are composed of a phosphate group, a sugar, & a nitrogen base

nucleosides

composed of only a base & a sugar, precursor to nucleotides

nucleotides

• building blocks of many nucleic acids

• composed of a phosphate group, sugar, & a base group