Macromolecules

1. Macromolecules Honors Biology

2. Macromolecules Are BIG molecules! • Building blocks of cells • Small monomers combine to form a polymer • All contain C, H, O

3. 4 Types • Proteins • Carbohydrates • Lipids • Nucleic Acids • *All are organic – so all contain Carbon

4. 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

5. Proteins • Have many different functions - as enzymes, transport of material, self-defense, structure of body

6. Proteins • Used mostly to build structures rather than for energy • Monomer = amino acids • Contains C, H, O, and N • Are millions of different kinds

7. 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

8. 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

9. Protein Examples • Connective tissues • Hair and nails • Transport proteins • Hormone proteins • Muscles • Enzymes

10. 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

11. Lipids • Phospholipids – make up structure of cell membrane • Other lipids – energy storage, signaling molecules, pigments

12. Lipids • Fats and oils – energy storage; some is needed in organisms • Saturated - solid at room temperature • Unsaturated - liquid

13. Lipids - Functions • Long term energy storage • Cushions internal organs • Insulation for body against temperature extremes • Important in hormones and vitamins

14. Lipid Base “Unit” • Does not have a “true” monomer • Triglyceride = 3 fatty acids + 1 glycerol • All lipids are “hydrophobic” (nonpolar)

15. 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

16. Lipids • Fats contain more energy (ATP) per gram than carbs or proteins - so have greater caloric value • Examples - Steroids, cholesterol, waxes, fats

17. 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

18. 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

19. Carbohydrates • Sugars and starches • Monosaccharides – glucose, fructose • Polysaccharides - starch, cellulose • Main source of energy for cells

20. 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)

21. Carbohydrates • Caloric value depends on number of C-H bonds • If excess carbs in body, extra energy converted to fats and stored in body

22. Starch and Glycogen • Energy storing polysaccharides • Plants store energy as starch • Animals store energy as glycogen in the liver and muscles

23. Nucleic Acids • Monomer = nucleotide • Polymer = DNA and RNA • Store and transmit the genetic material

24. Nucleotides • A 5-carbon sugar + a phosphate + a nitrogenous base • Information in DNA used to make proteins