2. Carbohydrates IB Biology

3. Molecular Models Kits In your groups, you have a kit. We will be making models with these over the next several class periods. To begin, in your warmup book, make a new page and title it, “Molecular Models Activity.” You will number each one, draw it, and get an initial. #1- Water, H 2 O #2- Methane, CH 4 Build these models now and get them initialed.

4. Review: Polymer Principles Four classes of macromolecules: –Carbohydrates –Lipids –Proteins –Nucleic Acids Polymers are made up of smaller parts called monomers. Polymers are formed through condensation reactions. Polymers are broken apart through a hydrolysis reaction.

5. General Information about Carbohydrates Carbohydrates are composed of C, H, and O CH 2 O (CH 2 O) x C 6 H 12 O 6 –“Carbo”-contains carbon –“Hydrate”- Compound containing chemically combined water. Often end in “-ose”

6. Is this a carbohydrate?

7. Is this a Carbohydrate?

8. Is this a carbohydrate?

9. Is this a Carbohydrate?

10. General info about carbohydrates Functions: –Immediate energy source for cells –Energy storage for later use –Raw material for building other molecules –Important role in cell membrane recognition About 17 KJ of energy per dry gram. About the same as protein, but ½ that of lipids

12. Monosaccharides -one sugar unit (monomer)– are the simplest carbohydrates Backbone of 3-7 carbon atoms Form ring structures in cells Characterized by sweet taste Have several polar -OH groups, so they are soluble in water. (The many –OH groups can hydrogen bond with water molecules)

13. Carbons are numbered

14. On your lab paper, draw Glucose Number the carbons

15. On your glucose, circle all the hydroxyl (–OH) groups

16. Label the slight positive and slight negatives on the highlighted O’s and H’s. HINT: Remember polarity and unequal pull of electrons

17. Using the molecular model kits, build a model of glucose Notice orientation of hydroxyl (OH) groups Initial when complete

18. Glucose C 6 H 12 O 6 A product of photosynthesis Needed for ATP synthesis during cellular respiration

19. Draw a water molecule hydrogen bonding off of EACH highlighted H and EACH highlighted O. –Be sure you correctly orient the H’s and O’s of the water molecule –Show the hydrogen bond with a dotted line (you should end up drawing 10 H2O’s)

20. Some example monosaccharides Glucose Ribose Deoxyribose Fructose

21. Deoxyribose and ribose are the building blocks for nucleic acids. Found in DNA Found in RNA**

22. Fructose Found in fruits Used by plants to attract animals to the fruit for seed dispersal.

23. Isomers Glucose and fructose have the same chemical formula C 6 H 12 O 6 but different structural arrangement of the atoms (called isomers)

24. The monosaccharides glucose, fructose, and galactose are isomers. They contain the same atoms but in different arrangements All are C 6 H 12 O 6

25. Disaccharides Di = 2 Saccharide = sugar

26. Disaccharides are formed in Condensation Reactions http://kisdwebs.katyisd.org/campuses/MRHS/teacherweb/hallk/Teacher%20Docu ments/AP%20Biology%20Materials/Chemistry%20of%20Life/Condensation%20 and%20Hydrolysis%20Reactions/conde_shell.html

28. Maltose (two glucose units) provides energy for germinating seeds. H2OH2O Formula: C 12 H 22 O 11 (glucose + glucose – H 2 O )

29. Maltose – between which carbon #’s are the glucoses connected? H2OH2O H2OH2O

30. Sucrose (glucose + fructose) is a transport form of sugar used by plants and harvested by humans for food.

31. Lactose (galactose and glucose) is present in milk

32. Splenda: A modified disaccharide Splenda is just a modified form of sucrose Notice the chloride ions that replace the hydroxyl groups

33. Maltose- (2 Glucoses) Malt Sugar

34. On your lab drawings paper, draw 2 glucoses next to each other. -On your first glucose, highlight the hydroxyl (-OH) on carbon 1. -On your second glucose, highlight the hydroxyl (-OH) on carbon 4.

35. Using the molecular model kits: BUILD MALTOSE Notice orientation of hydroxyl (-OH) groups.

36. When finished with maltose Combine each group’s maltose’s to make one long chain. Draw this. This is a model of starch.

37. Complex Carbohydrates: The Polysaccharides Polymers of hundreds or thousands of sugar monomers –costs little energy to build –easily reversible = release energy when digested

38. Storage Polysaccharides What does it mean to store something?

39. Storage Polysaccharides –Starch (polymer of glucose) Found in PLANTS Formed in roots and seeds as a form of glucose storage –Glycogen (polymer of glucose) Found in ANIMALS Formed in the liver and muscles as a form of glucose storage

41. Structural Polysaccharides Cellulose (polymer of glucose) –Most abundant organic compound on Earth –Found in the cell walls of plants –Indigestible for most animals due to orientation of bonds between glucoses

42. Structural Polysaccharides Chitin (polymer of modified glucose units) –Found in the outer coverings of insects, crabs, and spiders –Found in the cell walls of many fungi

44. Starch vs. Cellulose Starch: Polymer of  -glucose Highly branched Has  1-4 linkages Used for storage in plants. Cellulose Polymer of  -glucose Linear, does not branch Has  1-4 linkages Most animals lack the enzyme to break the  1- 4 linkages (so we can’t digest it).

45. Digesting starch vs. cellulose starch easy to digest enzyme cellulose hard to digest

46. Cow can digest cellulose well; no need to eat other sugars Gorilla can’t digest cellulose well; must add another sugar source, like fruit to diet

47. Helpful bacteria How can herbivores digest cellulose so well? –BACTERIA live in their digestive systems & help digest cellulose-rich (grass) meals Ruminants Tell me about the rabbits, again, George! I eat WHAT!

48. Summary of Carbohydrates Monosaccharides: Glucose, Fructose, Galactose, Ribose Disaccharides: Lactose, Maltose, Sucrose Polysaccharides: Starch, Cellulose, Glycogen, Chitin –Alpha (starch) & Beta (cellulose) linkages –Chitin: exoskeleton, suture, and fungi (cell walls)