Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
• Unit 2: Pre-test – Avg = 5 (out of 23) – Range = unknown • Termites – Follow Paper Mate ink – Acts as a pheromone • Test corrections – due tomorrow • I will scream sometime during class today. Chapter 5 The Structure and Function of Macromolecules Chapter 5 The Structure and Function of Macromolecules 1. What are the 4 major macromolecules? – – – – 2. Carbohydrates Proteins Lipids Nucleic acids How are they all similar? – – All large polymers made of smaller monomers All formed the same way Figure 5.2 The synthesis and breakdown of polymers HO 1 3 2 H Unlinked monomer Short polymer Dehydration removes a water molecule, forming a new bond HO Figure 5.2A 1 H HO 2 H2O 3 4 H Longer polymer (a) Dehydration reaction in the synthesis of a polymer HO 1 2 3 4 H Hydrolysis adds a water molecule, breaking a bond HO 1 2 3 H H2O HO Figure 5.2B (b) Hydrolysis in the breaking down of a polymer H Chapter 5 The Structure and Function of Macromolecules 1. 2. 3. What are the 4 major macromolecules? How are they all similar? What are carbohydrates & what are they made of? – – Sugars Made of monosaccharides • • • • CH20 Sugars end in -ose Nutrient for cells (1° glucose) Carbon skeleton is used for other organic molecules Figure 5.3 Examples of monosaccharides Triose sugars Pentose sugars (C3H6O3) (C5H10O5) H O H Aldoses C O H O C C OH H C OH H C OH H C OH H C OH HO C H C OH H H C OH H H H H C H C OH H HO C H C OH HO C H H C OH H C OH H C OH H C OH H H Glucose Galactose H C OH H C O H C OH H C OH C O O C OH H C OH HO H H C OH H C OH Dihydroxyacetone H C OH H C OH H H C OH H Ribulose O C H Ribose Ketoses H C Glyceraldehyde Figure 5.3 Hexose sugars (C6H12O6) C H H Fructose Figure 5.4 Linear & ring forms of glucose O H 1C H HO 2 3 C 6CH OH C H H C 5 5C H H 4 H 2OH 6 C H OH 4C OH OH OH O 3 C H 2C 2OH 5C H H OH C 6CH O H H 4C 1C CH2OH O OH H OH 3C 6 H 1C H 2C 4 HO H OH 3 OH H H 1 2 OH OH H H O 5 OH OH H Figure 5.4 (a) Linear and ring forms. Chemical equilibrium between the linear and ring structures greatly favors the formation of rings. To form the glucose ring, carbon 1 bonds to the oxygen attached to carbon 5. Chapter 5 The Structure and Function of Macromolecules 1. 2. 3. 4. What are the 4 major macromolecules? How are they all similar? What are carbohydrates & what are they made of? How are monomers added to carbs? (a) Dehydration reaction in the synthesis of maltose. The bonding of two glucose units forms maltose. The glycosidic link joins the number 1 carbon of one glucose to the number 4 carbon of the second glucose. Joining the glucose monomers in a different way would result in a different disaccharide. CH2OH CH2OH H O H OH H HO H H H OH HO O H OH H OH H OH CH2OH H OHOH H O H OH H HO CH2OH H 1–4 1 glycosidic linkage Glucose 4 O H OH H H H OH Maltose H OH O H2O Glucose H OH Chapter 5 The Structure and Function of Macromolecules 1. 2. 3. 4. 5. What are the 4 major macromolecules? How are they all similar? What are carbohydrates & what are they made of? How are monomers added to carbs? What are polysaccharides used for? – Energy storage • • – Starch – plants Glycogen – animals Structural support • • Cellulose Chitin Chapter 5 The Structure and Function of Macromolecules Chloroplast Starch Mitochondria Giycogen granules 0.5 m 1 m Amylose Amylopectin (a) Starch: a plant polysaccharide Glycogen (b) Glycogen: an animal polysaccharide H H 4 CH2O H O H OH H H OH HO H OH glucose (a) O CH2O H O H OH H C H C OH H HO C H 4 H C OH H C OH H C OH OH 1 HO H H OH glucose and glucose ring structures CH2O H O CH2O H O HO 4 1 OH O CH2O H O HO (c) Cellulose: 1– 4 linkage of glucose monomers 1 OH 6. Why do we poop corn? 4 OH O CH2O H 1 OH O 4 OH O OH OH O OH CH2O H O O 1 OH OH OH O OH 4 O OH OH (b) Starch: 1– 4 linkage of glucose monomers 1 OH CH2O H O CH2O H O OH O CH2O H OH Chapter 5 The Structure and Function of Macromolecules Cellulose microfibrils in a plant cell wall Cell walls Microfibril About 80 cellulose molecules associate to form a microfibril, the main architectural unit of the plant cell wall. 0.5 m Plant cells OH CH2OH OH CH2OH O O O O OH OH OH OH O O O O O CH OH OH CH2OH 2 OH Parallel cellulose molecules are held together by hydrogen bonds between hydroxyl groups attached to carbon atoms 3 and 6. CH2OH OH CH2OH OH O O O O OH OH OH OH O O O O O OH CH2OH OH CH2OH CH2OH OH OH CH2OH O O O O OH OH OH O O OH O O O CH OH OH CH OH 2 2OH Glucose Figure 5.8 Cellulose monomer Cellulose molecules A cellulose molecule is an unbranched glucose polymer. Chapter 5 The Structure and Function of Macromolecules H OH CH2OH O OH H OH H H H NH C O CH3 (a) The structure of the chitin monomer. (b) Chitin forms the exoskeleton of arthropods. This cicada is molting, shedding its old exoskeleton and emerging in adult form. (c) Chitin is used to make a strong and flexible surgical thread that decomposes after the wound or incision heals. Chapter 5 The Structure and Function of Macromolecules 1. 2. 3. 4. 5. 6. 7. What are the 4 major macromolecules? How are they all similar? What are carbohydrates & what are they made of? How are monomers added to carbs? What are polysaccharides used for? Why do we poop corn? What are some common lipids? – – – – – Fats Phospholipids Steroids Oils Waxes Chapter 5 The Structure and Function of Macromolecules 1. 2. 3. 4. 5. 6. 7. 8. What are the 4 major macromolecules? How are they all similar? What are carbohydrates & what are they made of? How are monomers added to carbs? What are polysaccharides used for? Why do we poop corn? What are some common lipids? How are fats made? Figure 5.11 The synthesis and structure of a fat, or triacylglycerol H H C O H C OH HO H H C C C H OH H C H H C H H C H H H C C H H H C H H C H H C H H C H H C H H C H H C H H C H Fatty acid (palmitic acid) OH H Glycerol (a) Dehydration reaction in the synthesis of a fat Ester linkage O H H C O C H C H O H C O C H C H O H C H O C H C H H C H H C H H C H H C H H C H H C H H C H H C H H C H H C H H C H H C H H C H H C H H C H (b) Fat molecule (triacylglycerol) H C H H C H H C H H C H H C H H C H H C H H C H H C H H C H H C H H C H H C H H C H H C H H C H H C H H C H H C H H C H H C H H C H H C H H C H H C H H H C H H H C H H H C H H Chapter 5 The Structure and Function of Macromolecules 1. 2. 3. 4. 5. 6. 7. 8. 9. What are the 4 major macromolecules? How are they all similar? What are carbohydrates & what are they made of? How are monomers added to carbs? What are polysaccharides used for? Why do we poop corn? What are some common lipids? How are fats made? What is the difference between a saturated & unsaturated fat? Figure 5.12 Examples of saturated and unsaturated fats and fatty acids Stearic acid (a) Saturated fat and fatty acid Oleic acid (b) Unsaturated fat and fatty acid cis double bond causes bending Staple test corrections to test & place in box Saturated vs Unsaturated Fats - No double bonds (C-C) Carbons are saturated Solid at RT Animal fats Butter Bacon grease What are trans fats? - Formed by hydrogenation - C=C without the “kink” - Double bonds (C=C) - Carbons not saturated - Oil at RT - Plant or fish fats - Vegetable oil - Olive oil Saturated vs Unsaturated Fats - No double bonds (C-C) Carbons are saturated Solid at RT Animal fats Butter Bacon grease What are the functions of fats? - Energy storage (2X carbs) - Cushion - Insulation - Double bonds (C=C) - Carbons not saturated - Oil at RT - Plant or fish fats - Vegetable oil - Olive oil Figure 5.13 The structure of a phospholipid +N(CH ) CH2 3 3 Choline CH2 O O P – O Phosphate Amphipathic – molecules both polar & non-polar O CH2 CH O O C O C CH2 Glycerol O Fatty acids Hydrophilic head Hydrophobic tails (a) Structural formula (b) Space-filling model (c) Phospholipid symbol Figure 5.14 Bilayer structure formed by self-assembly of phospholipids in an aqueous environment WATER Hydrophilic head WATER Hydrophobic tail Figure 5.15 Cholesterol, a steroid H3C CH3 CH3 HO CH3 CH3 Chapter 5 The Structure and Function of Macromolecules 10. What are the monomers of proteins? Amino acids 11. How are all amino acids similar? carbon R O H N C C OH H H Amino group Carboxyl group Figure 5.17 The 20 amino acids of proteins CH3 CH3 H H3N+ C CH3 O H3N+ C H Glycine (Gly) O– C H3N+ C H Alanine (Ala) O– CH CH3 CH3 O C CH2 CH2 O H3N+ C H Valine (Val) CH3 CH3 O– C O H3N+ C H Leucine (Leu) H3C O– CH C O C H Isoleucine (Ile) O– Nonpolar CH3 CH2 S NH CH2 CH2 H3N+ C H CH2 O H3N+ C O– Methionine (Met) C H CH2 O H3N+ C C O– Phenylalanine (Phe) H O H2C CH2 H2N C O C O– H C O– Tryptophan (Trp) Proline (Pro) OH OH Polar CH2 H3N+ C CH O H3N+ C O– H Serine (Ser) C CH2 O H3N+ C O– H C CH2 O C H O– H3N+ C O H3N+ C O– H Electrically charged H3N+ CH2 C H3N+ O– C NH3+ O C CH2 C CH2 CH2 CH2 CH2 CH2 CH2 O CH2 C O– H H3N+ C O CH2 C H O– H3N+ C H O– H Glutamic acid (Glu) NH+ C O– Lysine (Lys) NH2+ H3N+ CH2 O CH2 H3N+ C H Aspartic acid (Asp) O C Glutamine (Gln) NH2 C C C Basic O– O O Asparagine (Asn) Acidic –O CH2 CH2 H Tyrosine (Tyr) Cysteine (Cys) Threonine (Thr) C NH2 O C SH CH3 OH NH2 O NH CH2 O C C O– H O C O– Arginine (Arg) Histidine (His) Chapter 5 The Structure and Function of Macromolecules 10. What are the monomers of proteins? 11. How are all amino acids similar? 12. How are amino acids connected? Dehydration (condensation) rxn Creates a peptide bond Figure 5.18 Making a polypeptide chain Peptide bond OH CH2 SH CH2 H N H OH C C CH2 H H N C C OH H N C H O H O H (a) C OH O DESMOSOMES H2O OH DESMOSOMES DESMOSOMES OH CH2 H H N C C H O (b) Amino end (N-terminus) Side chains SH Peptide CH2 bond CH2 H H N C C H O N C C H O Carboxyl end (C-terminus) OH Backbone Chapter 5 The Structure and Function of Macromolecules 10. What are the monomers of proteins? 11. How are all amino acids similar? 12. How are amino acids connected? 13. What are the 4 levels of protein structure? 1° (Primary) – aa sequence (determined by DNA sequence) 2° (Secondary) – based on H-bonds 3° (Tertiary) – overall globular shape – 3D structure 4° (Quaternary) – several 3° polypeptides (subunits) Figure 5.20 Primary structure of a protein • Based on amino acid sequence • Each protein has a unique sequence • Like the alphabet (letters = aa) Gly Pro Thr Gly Thr +H N 3 Amino acid subunits Gly Amino end Leu Seu Pro Cys Lys Glu Met Val Lys Val Leu Asp Ala Val Arg Gly Ser Pro Ala Glu Lle Asp Thr Lys Ser Tyr Lys Trp Leu Ala Gly lle Ser Pro Phe His Glu His Ala Glu Ala Thr Phe Val Val Asn Asp Arg Ser Gly Pro Thr Tyr Thr lle Ala Ala Arg Leu Ser Tyr Ser Tyr Pro Leu Ser Thr Ala Val Val Thr Asn Pro Lys Glu c o o– Carboxyl end Figure 5.20 Secondary structure of a protein pleated sheet Amino acid subunits H O O H R C N H C C N C N C C R O H H O C C R H N O N O C H C H O R H C R H O C N O C C R N C Based on H-bonds • α-helix • adjacent polar aa H H R H C C N H C C N O H H R C H N HC N H C H C O R C H H C C N O R C C N O H H R O H H N H C N C H C O R C C C O R R O H H N H C N C H C O R H C N H C N H C O H H helix R H C R H O C N O R R C O N C H C C N H H C C N O H R R O H C R N C H H - β-pleated sheet - after folding, polar aa become neighbors and form H-bonds Figure 5.20 Tertiary structure • overall globular shape – 3D structure • each protein has unique 3D shape • recall carbon sets the 3D shape • based on 1° structure (aa sequence) • rearranged the alphabet to get new words • Disulfide bridge • 2 cysteine amino acids • covalent bond • van der Waals interactions • hydrophobic interactions • ionic bonds • occasional H-bonds Hydrogen bond CH CH2 H3C CH3 H3C CH3 CH O H O Hydrophobic interactions and van der Waals interactions OH C CH2 CH2 S S CH2 Disulfide bridge O CH2 NH3+ -O C CH2 Ionic bond Polypeptide backbone Figure 5.20 Quarternary structure • more than one 3° polypeptide (subunit) needed for biological activity • not all proteins have quarternary structure • # of subunits varies by protein Polypeptide chain Collagen Chains Iron Heme Chains Hemoglobin Chapter 5 The Structure and Function of Macromolecules 10. What are the monomers of proteins? 11. How are all amino acids similar? 12. How are amino acids connected? 13. What are the 4 levels of protein structure? 14. How much does sequence (structure) influence function? - Sickle cell anemia Figure 5.21 A single amino acid substitution in a protein causes sickle-cell disease Primary structure Normal hemoglobin Val His Leu Glu Glu Sickle-cell hemoglobin Val His Leu Molecules do not associate with one another; each carries oxygen Normal cells are full of individual hemoglobin molecules, each carrying oxygen Thr Pro Val Glu ... structure 1 2 3 4 5 6 7 Secondary subunit and tertiary structures Quaternary Hemoglobin A structure Red blood cell shape Pro 1 2 3 4 5 6 7 Secondary and tertiary structures Function Thr . . . Primary Quaternary structure subunit Function 10 m 10 m Red blood cell shape Hemoglobin S Molecules interact with one another to crystallize into a fiber, capacity to carry oxygen is greatly reduced Fibers of abnormal hemoglobin deform cell into sickle shape Chapter 5 The Structure and Function of Macromolecules 10. What are the monomers of proteins? 11. How are all amino acids similar? 12. How are amino acids connected? 13. What are the 4 levels of protein structure? 14. How much does sequence (structure) influence function? 15. What happens to proteins if they get too hot or experience a change in pH? Denaturation Denatured protein Normal protein Renaturation Chapter 5 The Structure and Function of Macromolecules 10. What are the monomers of proteins? 11. How are all amino acids similar? 12. How are amino acids connected? 13. What are the 4 levels of protein structure? 14. How much does sequence (structure) influence function? 15. What happens to proteins if they get too hot or experience a change in pH? 16. What do proteins do? Table 5.1 Protein function ↓ Chapter 5 The Structure and Function of Macromolecules 10. What are the monomers of proteins? 11. How are all amino acids similar? 12. How are amino acids connected? 13. What are the 4 levels of protein structure? 14. How much does sequence (structure) influence function? 15. What happens to proteins if they get too hot or experience a change in pH? 16. What do proteins do? 17. What are the different types of nucleic acids? DNA – deoxyribonucleic acid RNA – ribonucleic acid - mRNA – messenger - tRNA – transfer - rRNA – ribosomal 18. What are the monomers of nucleic acids? 19. What makes up the monomers? Figure5.26 Components of nucleic acids Nitrogenous bases Pyrimidines 5’ end 5’C NH2 O Nucleoside O Nitrogenous base O O 5’C O 3’C C CH CH 5’C O P O Purines CH2 O O Phosphate 3’C Pentose group sugar O NH2 HC N C C N N C N H Adenine A (b) Nucleotide OH 3’ end (a) Polynucleotide, or nucleic acid O C C CH3 HN C HN CH C CH C C CH N N O N O O H H H Cytosine Thymine (in DNA) Uracil (in RNA) C U T N 3’C O HC N C N H Guanine G Pentose sugars 5’ HOCH2 O 4 H H H CH N C C NH 3’ 2’ OH 1’ H OH H Deoxyribose (in DNA) C NH2 5’ HOCH2 O OH 4 H H 1’ H 3’ 2’ H OH OH Ribose (in RNA) (c) Nucleoside components Figure 5.27 DNA Double helix 3 end 5 end G C Sugar-phosphate backbone G C A T C G A T A T G C A A A Old strands T T A T Base pair (joined by hydrogen bonding) Nucleotide about to be added to a new strand 3 end 5 end New strands 3 end 5 end 5 end 3 end