Carbohydrates and Lipids

4 basic macromolecules

lipids (fats), carbs (sugars), nucleic acids (genetic code), proteins (enzymes and building blocks)

building macromolecules

monomer (simplest unit), polymer (made up of monomers)

dehydration/condensation synthesis

builds complex molecules by removing H2O and replacing it with a bond, water released, builds complexity, requires energy

hydrolysis

adds water to break down molecules into smaller units, releases energy, enzymes required

glucose

single rings, soluble in water, can be oxidized, chemically stable

disaccharide examples

maltose (malt sugar: glucose, glucose), sucrose (table salt: glucose, fructose), lactose (milk sugar: glucose, galactose)

structural support

cellulose (major component of plant cell walls), starch (alpha linked), cellulose (beta linked)

cellulose

plant, beta-glucose, 1-4 bonds, no branches, forms microfibrils held together by hydrogen bonds that have high tensile strength

starch (amylose)

plant, alpha-glucose, 1-4 bonds, no branches, long chains of alpha glucose molecules, large and not soluble in water, compact storage of starch and grains

starch (amy

plant, alpha-glucose, 1-4 and 1-6 bonds, branches per 20 subunits, long chains of alpha glucose with branching chains of alpha glucose, large and not soluble in water, compact storage of starch and grains

glycogen

animal, alpha-glucose, 1-4 and 1-6 bonds, branches per 10 subunits

modified polysaccharide

chitin and peptidoglycan

lipids examples

palmitic acid (animal fat component), linoleic acid (plant oil component), octadecanoic acid (wax on leaves), cholesterol (membrane component)

triglycerides

condensation reaction between one glycerol and 3 fatty acids

lipid functions

long term energy storage and insulation, no polymers, 3 major groups: triglycerides, phospholipids, steroids

lipid condensation reaction

hydroxyl groups of glycerol combine with the carboxyl groups of fatty acids to form an ester linkage, stored in adipose tissue of animals, different types of lipids are determined by the # of C-H bonds in the fatty acid chain

saturated fatty acid

maximum # of C-H bonds, solid, high boiling point

unsaturated fatty acid

one double c-c bond, liquid at room temp, low boiling point

polyunsaturated fatty acid

many double c-c bonds, liquid at room temperature, low boiling point

phospholipids

modified triglycerides (replace fatty acid with a phosphate), polar hydrophilic head and nonpolar hydrophobic tail (amphipathic), 1 glycerol molecule, 2 fatty acids, 1 phosphate

steroids

fall into lipid category, class of hormones and cholesterol, fused ring structure (3 hexose, 1 pentose), hydrocarbon chain, different functional groups = different functions, hydrophobic, can diffuse directly through a phospholipid bilayer, can dissolve in hydrophobic fatty acid tails on the inside of the bilayer (ex. oestradiol and testosterone)

fatty acids

unbranched, plants and fish use oil as energy storage, many c-c bonds, carboxyl group, hydroxyl chain, menthyl group

triglycerides

branched chains, one glycerol molecule, 3 fatty acid molecules

cholesterol

multiple rings

monosaccharide

1 sugar molecule (ex. glucose, ribose, fructose)

disaccharide

2 sugar molecules (ex. sucrose, maltose, lactose)

polysaccharide

many sugar molecules (ex. starch, glycogen, cellulose, chitin)

aldose

glyceraldehyde, ribose, glucose, galactose

ketose

dihydroxyacetone, ribulose, fructose

monomer examples

glucose, amino acid, nucleotide, fatty acids and glycerol

polymer examples

polysaccharide, polypeptide, polynucleotide, triglyceride

macromolecule examples

amylose and amylopectin, proteins, DNA and RNA, fats and oils

starch

composed of 2 polysaccharide molecules

glycoproteins

integral proteins located within phospholipid bilayers of cells, always have a chain of carbohydrates attached, specific shape and can act as an antigen

glycoprotein functions

cell to cell adhesion, cell to cell communication, hormone receptor, immune response (distinguishes self and non-self)