Biological Molecules

1. Biological Molecules • The Building Blocks of Life

2. W O R K T O G E T H E R • Before we begin, get out a piece of paper, put your name on it, and do the following: • As review, sketch a diagram of an atom and label the particles. • Sketch a water molecule, and state what kind of bonds form between the oxygen and hydrogen atoms in water.

3. Which four elements make up about 96% of living matter? • carbon, hydrogen, nitrogen, oxygen • carbon, sulfur, phosphorous, hydrogen • carbon, oxygen, sulfur, calcium • oxygen, hydrogen, calcium, sodium

4. An atom of nitrogen attracts electrons more strongly than an atom of hydrogen. Which of the following best describes ammonia (NH3)? • The nitrogen is slightly negative. • The nitrogen is strongly positive. • The hydrogens are slightly negative. • The hydrogens are strongly positive.

5. Carbon is the backbone of organic molecules. With an atomic number of 6, carbon can form up to ___ different ___ bonds. • 6; ionic • 6; covalent • 4; ionic • 4; covalent

6. Atoms to Molecules

7. In our model of scale, remember that the marble represented a small monomer, such as glucose.

8. Functional Groups Functional groups determine how a molecule will interact with other molecules. Why does sugar dissolve in water?

10. The methyl group, consisting of carbon bonded to hydrogen, is an area of ___ in an organic molecule. • Polarity • Non-polarity

11. If you see oxygen or nitrogen in the structure of an organic molecule, expect that area to be: • Polar • Non-polar

12. One glucose molecule alone is a monomer. Two or more glucose molecules linked together can make a polymer.

13. Dehydration Synthesis Two glucose molecules (monomers)... ...can bond together to make maltose (dimer).

14. Hydrolysis ...can be broken apart into its constituent monomers. A dimer such as maltose, or any other polymer...

15. Making/Breaking Molecules Monomers or Polymers? The process occurring between C and A is: The process occurring between A and C is: Hydrolysis Dehydration Synthesis What is given off here? What is taken up here? H2O H2O Monomer or Polymer?

16. In our model of scale, large chain molecules (polymers) are represented by the cat.

17. Carbohydrates

18. Monomers Simple sugars, such as glucose, are the monomers of complex carbohydrates. Label a hydrogen group and hydroxyl group on the glucose diagram. What are some properties of these groups?

19. What is similar about these four simple sugars? What is different?

20. glucose fructose sucrose What process do you see happening here to create this glycosidic linkage between the two sugars? What is the scientific term for a pair of monomers linked together?

21. Glycosidic linkages between many sugar molecules create complex carbohydrates, such as starch. What is the scientific term for many monomers linked together?

22. Cellulose Hemp Cotton Rayon Dietary “fiber” Linen

23. What do you see in the structure of cellulose that tells you that it is a carbohydrate? How is cellulose similar to starch?

24. Cellulose vs. Starch We can digest starch (amylose) but not cellulose. What difference do you see that might be the reason behind this?

25. Chitin Pectin In general, how can we describe complex carbohydrates?

26. White death? Some people claim that sugar is harmful, toxic, or addictive. Is it? http://ed.ted.com/lessons/how-sugar-affects-the-brain-nicole-avena

27. Fake sugar?

28. Polymers of simple sugars. Monomers of simple sugars. Complex carbohydrates are:

29. True False True or false: Sugars and starch have a lot of fat in them.

30. W O R K T O G E T H E R • Look around you. What are some specific examples of carbohydrates that are in this room right now? • List some specific carbohydrates that you ate for breakfast. Not the foods that they were in – name the carbohydrates themselves.

31. Lipids

32. Label a methyl group and a hydroxyl group on one of the fatty acids. What are some properties of these groups? What process do you see happening here to create these ester bonds between the fatty acid chains and the glycerol in this triglyceride?

33. Lipids that are solid at room temperature are composed mostly of saturated fatty acids. Stearic acid (found in wax and lard) and butyric acid (found in butter) are examples of saturated fatty acids.

34. Lipids that are liquid at room temperature are composed mostly of unsaturated fatty acids. Oleic acid and linoleic acid are unsaturated fatty acids that are common in vegetable oils.

35. Saturated vs. Unsaturated

36. A puzzle: Shortening and margarine labels often brag that their products are made with healthy, unsaturated vegetable oils. Vegetable oils are liquid at room temperature. So why are shortening and margarine solid at room temperature?

38. Trans fats? Unsaturated fats bend because of the cis configuration Trans configuration results in an unsaturated fatty acid that is a straight chain like a saturated fatty acid Trans fats are rare in nature. Hydrogenation can create both saturated and trans fatty acids.

39. Phospholipids Saturated or unsaturated? Label the phosphate group on this phospholipid. What are some properties of this group?

40. Steroids

41. Fake fat? What do you see in this molecular structure that suggests why Olestra is not digested? Why might it cause the symptoms described on the label?

42. W O R K T O G E T H E R • List some examples of lipids or fatty acids – not the foods that contain them, but specific lipids. • How are carbohydrates and lipids different from one another?

43. A chain of carbon and hydrogen atoms. A chain of sugar molecules. A chain of any carbon-containing monomers. A fatty acid consists of:

44. Oil floats on water. Oil is more dense than water. Oil is non-polar, while water is polar. Oil is an organic molecule, while water is not. Why can’t you mix oil and water?

45. Which of these is the largest object? • A carbon atom. • A fatty acid. • A phospholipid. • A cell membrane.

46. Proteins

47. Monomers Amino group Carboxylic acid group Amino acids are the monomers of proteins. On your diagram, label the amino group and the carboxylic acid group. What are some properties of these groups?

48. R-groups determine the properties of individual amino acids.

50. What process do you see happening here to create this peptide bond between the two amino acids? What is the scientific term for many monomers linked together?