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Macromolecules. Honors Biology. Macromolecules. Are BIG molecules! Building blocks of cells S mall monomers combine to form a polymer All contain C, H, O. 4 Types. Proteins Carbohydrates Lipids Nucleic Acids *All are organic – so all contain Carbon. Caloric Value.
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Macromolecules Honors Biology
Macromolecules Are BIG molecules! • Building blocks of cells • Small monomers combine to form a polymer • All contain C, H, O
4 Types • Proteins • Carbohydrates • Lipids • Nucleic Acids • *All are organic – so all contain Carbon
Caloric Value • Energy in macromolecules is stored in the bonds that link smaller units together • Amount of energy stored varies with type of molecule formed • Proteins, carbs, lipids - different structures so different caloric values
Proteins • Have many different functions - as enzymes, transport of material, self-defense, structure of body
Proteins • Used mostly to build structures rather than for energy • Monomer = amino acids • Contains C, H, O, and N • Are millions of different kinds
Amino Acids – 20 different kinds • A.A.’s bond together by “peptide” bonds • Forms a polymer called a polypeptide • Different A.A.’s have different chemical properties
Proteins – Caloric Value • Amino acids - 12 are made in body; rest come from food • Same caloric value as carbs per gram • Proteins used for energy ONLY IF carbs or lipids not available
Protein Examples • Connective tissues • Hair and nails • Transport proteins • Hormone proteins • Muscles • Enzymes
Enzymes • A type of protein • Help control chemical reactions (speeds them up) • If you’re missing an enzyme, the chemical reaction it controls happens too slowly
Lipids • Phospholipids – make up structure of cell membrane • Other lipids – energy storage, signaling molecules, pigments
Lipids • Fats and oils – energy storage; some is needed in organisms • Saturated - solid at room temperature • Unsaturated - liquid
Lipids - Functions • Long term energy storage • Cushions internal organs • Insulation for body against temperature extremes • Important in hormones and vitamins
Lipid Base “Unit” • Does not have a “true” monomer • Triglyceride = 3 fatty acids + 1 glycerol • All lipids are “hydrophobic” (nonpolar)
Lipids • Have more C-H bonds than carbs so used for long term storage of energy • Used for energy when carbs are scarce; otherwise are stored
Lipids • Fats contain more energy (ATP) per gram than carbs or proteins - so have greater caloric value • Examples - Steroids, cholesterol, waxes, fats
Carbohydrates • Always made of C, H and O; forms long chains • Energy storage, cell structure, signaling • monomer = monosaccharide or “simple sugar” • Forms disaccharides and polysaccharides = polymers
Carbohydrates • When broken down by digestion, C-H-O can be used as raw materials for amino acids, fatty acids and other organic compounds. • Important source of fiber for animals. Most fiber is cellulose
Carbohydrates • Sugars and starches • Monosaccharides – glucose, fructose • Polysaccharides - starch, cellulose • Main source of energy for cells
Carbohydrates • Bonds break during digestion; energy is released and simple sugars absorbed through wall of intestine • Blood carries sugars to cells • Inside cells, sugars used as fuel during cell respiration (energy stored as ATP)
Carbohydrates • Caloric value depends on number of C-H bonds • If excess carbs in body, extra energy converted to fats and stored in body
Starch and Glycogen • Energy storing polysaccharides • Plants store energy as starch • Animals store energy as glycogen in the liver and muscles
Isomers of Carbohydrates • Compounds with same chemical formula but different chemical structure. • Glucose and Galactose
Making Polymers • Condensation– joining two monosaccharides(monomers) results in a disaccharide + water (which is given off) Lactose is a disaccharide
Breaking down Polymers • Hydrolysis - Bonds broken by additionof water; breaks down into monomers. H and OH fill in gaps where bond was broken.
Functional Groups • Many macromolecules have functional groups; gives it specific chemical properties • OH = alcohol • COOH = carboxyl • NH₂ = amine Ethanol
Nucleic Acids • Monomer = nucleotide • Polymer = DNA and RNA • Store and transmit the genetic material
Nucleotides • A 5-carbon sugar + a phosphate + a nitrogenous base • Information in DNA used to make proteins