BIOCHEMISTRY WS #1WATER:

Examine the chemical formula for water, H2O. H represents the element Hydrogen. O represents the element Oxygen. The number 2 represents the number of atoms of Hydrogen. A number called a subscript, following a chemical symbol indicates the number of atoms of that particular element. No subscript indicates that there is only one atom. The number in front of the chemical formula or the coefficient indicates the number of molecules. No coefficient indicated that there is one molecule present. A molecular formula shows the total number of atoms for each element in the molecule. The molecular formula for water is H2O. A structural formula attempts to show the 3-D arrangement of the molecules.

The lines represent bonds between atoms.

The structural formula for water is:

Properly label the polar molecule with its positive & negative ends.

What property of water makes it a universal solvent?

CARBOHYDRATES: (Color the molecules involved with carbohydrates according to the color code.)

Carbohydrates contain three different elements: Carbon (C), Hydrogen (H), and Oxygen (O). There are many different types of carbohydrates. They have been placed into three groups — Monosaccharides, Disaccharides, and polysaccharides.

A. Monosaccharides (single molecule sugars)

Three examples of Monsaccharides are glucose, fructose, and galactose. Examine the structural formulas for these three sugars.

1. What are the elements that are present in glucose, fructose, and galactose?

2. How many carbon atoms are present in a molecule of:

a. glucose _________

b. fructose _________

c. galactose_ ________

3. Write the proper molecular formula for each monosaccharide. Do this by counting the total number of Carbon, Hydrogen, and Oxygen atoms in each molecule.

a. glucose C___H___O___

b. fructose C___H___O___

c. galactose C___H___O___

4. How many times larger is the number of Hydrogen atoms than the Oxygen atoms in a molecule of:

a. glucose ________

b. fructose _______

c. galactose_______

5. How many times larger is the number of Hydrogen atoms than the Oxygen atoms in a molecule of water?

The prefix “mono” means one. Monosaccharides are sugars that are made up on only one molecule. Thus, they are called single sugars. The one molecule, however, can have different shapes due to a different arrangement of atoms. Compare the structural formula of glucose and fructose.

6. Are glucose and fructose exactly the same shape?

7. Are they both monosachharides?

B. Disaccharides (double molecule sugars)

Two monosaccharide sugar molecules can join together chemically to form a larger carbohydrate molecule called a double sugar, or disaccharide. The prefix “di” means two. By chemically joining glucose molecule with a fructose molecule a double sugar called sucrose is produced.

Cut out glucose and a fructose paper model. Cut along the solid lines only. Attempt to join the two molecules together like a puzzle piece.

8. Do the glucose and fructose fit easily together?

In order to join these molecules, you must remove the —OH end from one molecule and a —H end from the other. Cut along the dotted lines. Place these models on a sheet of unlined white paper and name the molecule formed.

9. The OH and H ends that were removed can also fit together to form a molecule. What is the name of this molecule?

10.What is its molecular formula?

11. Write the molecular formula for sucrose by adding the molecular formulas for glucose and fructose together and then subtracting the water.

Formula for glucose C___H___O___

Formula for fructose + C___H___O___

Formula for water - H___O___

Formula for sucrose C___H___O___

Joining other Monosaccharides in different combinations can make different disaccharide molecules. By chemically joining a glucose molecule with another glucose molecule, a double sugar maltose is formed.

Cut out and attempt to join two glucose molecules together like puzzle pieces.

12. Do they easily fit together to form maltose?

13. What must be removed in order for them to fit together?

In order to join the molecules, remove an —OH end from one molecule and an —H end from another. Cut along the dotted lines. Place these models on your sheet of unlined paper and name the molecule.

14. Write the molecular formula for maltose. (Use #11 as a guide)

15. How does the molecular formula of sucrose compare to the molecular formula of maltose?

16. How many times larger is the number of Hydrogen atoms than Oxygen atoms in disaccharide?

17. How many Monosaccharides are needed to form one sucrose molecule?

C. Polysaccharides: (many molecule sugars)

Just as double sugars were formed from two single sugar molecules, polysaccharides are formed when many single sugars are joined chemically together. The prefix “poly” means many. Starch, glycogen, and ce1lulose are the three most common polysaccharides in biology. They consist of long chains of glucose molecules joined together.

Construct a starch molecule by joining three glucose molecules together. This will represent only a small part of a starch molecule because starch molecules consist of hundreds of glucose molecules joined together.

20. What must be removed from the glucose molecules in order for them to fit together?

The molecular formula for a polysaccharide is written as (C6H10O5)n. The n equals the number of times the C6H10O5 group is repeated. You can see this group as the middle glucose of your model. REMEMBER: The —H and —OH ends of the middle molecule are missing.

21. What is the smallest number of glucose molecules needed in order to form a polysaccharide?

22. How many times larger is the Hydrogen atom than the Oxygen atom in a polysaccharide?

In order to join the molecules, remove an —OH from one molecule and an —H from another molecule. Place these models on your unlined white paper and name the molecule.

Name _______________________________ Block ____________ Date _______________

BIOCHEMISTRY WS #2FATS: (Color the molecules involved with carbohydrates according to the color code.)

To better understand the chemistry of fats, it is helpful to first study the small molecules that join to make up fats. Fat molecules are made up of two different kinds of chemical molecules. These are glycerol and fatty acids.

A. Glycerol:

Examine the structural formula of glycerol.

23. What elements are present in glycerol?

24. Are there any elements in glycerol that are not in carbohydrates?

25. Compare the number of Hydrogen and Oxygen atoms present in glycerol.

B. Fatty Acids:

The second kind of molecule, which is part of a fat, is a fatty acid. Many different fatty acids exist but all are similar in several ways. Butyric acid, caproic acid, and lauric acid are a few examples. Examine the structural formulas of the three molecules below.

26. What elements are present in all fatty acids?

27. What is the molecular formula for butyric fatty acid?

28. What is the molecular formula for lauric fatty acid?

29. What is the molecular formula for caproic fatty acid?

30. What pattern appears in the fatty acid molecules regarding the number of Oxygen atoms?

31. Notice the end of butyric acid containing the Oxygen atoms. This special arrangement of Carbon, Hydrogen, and Oxygen is called a carboxyl group.

32. Is the carboxyl group present in the fatty acids shown above?

33. List any similarities between glycerol and fatty acids.

34. Do fatty acids and glycerol both contain a carboxyl group?

A fat molecule consists of one glycerol and three fatty acid molecules joined together.

Cut out the glycerol and fatty acid paper models. Cut along the solid lines only. Construct a fat molecule.

35. Will the fat molecule fit together like pieces in a puzzle?

Remove the three —OH ends from the glycerol molecule and the three —H ends from the fatty acids. Now join the molecules to form a fat and place them on your unlined paper. Label it.

36. How many fatty acid molecules are needed to form a fat molecule?

Join the all the left over OH and H ends to form a molecule. Place them on your unlined paper. Label it.

37. What chemical substance is formed when the OH and H ends are joined?

Production of a fat molecule is a chemical reaction. A chemical shorthand way of expressing the formation of a fat is as follows:

Glycerol + 3 fatty acid molecules = fat + water molecules

38. How many water molecules were formed from the production of one fat molecule?

Many fats exist in living things. Different combinations of fatty acid molecules form the wide varieties of fats.

39. What molecule stays the same in fats?

Name _______________________________ Block ____________ Date _______________

BIOCHEMISTRY #3PROTEINS:

(Color the molecules involved with carbohydrates according to the color code.)Proteins are complex molecules made up of simpler building blocks called amino acids. Examine the structural formulas of the four amino acids shown below.

The element Nitrogen (N) is present in amino acids.

40. Is Nitrogen present in fats and carbohydrates?

41. What is the molecular formula for the amino acid glycine?

42. What is the molecular formula for the amino acid alanine?

43. What is the molecular formula for the amino acid threonine?

44. Are all the molecular formulas for all amino acids the same?

45. What end arrangement of atoms is present in amino acids that are also present in fatty acids?

Another end arrangement in all amino acids consists of a Nitrogen atom and two Hydrogen atoms. This group is called an amino group.

46. Do all structural formulas of amino acids have the amino group?

Protein is composed of many amino acids joining together chemically.

Cut out four amino acid models. Cut along the solid lines only. Attempt to join the amino acids.

47. Will the protein molecule fit together?

Join the molecules by removing as many OH and H groups as needed from the amino acids. All four molecules can be joined together in this manner to form a protein.

Join them in the order: Valine — Threonine — Alanine -- Glycine

Rejoin the left over OH and H ends. Place all molecules on your unlined paper and label them.

48. How many molecules of water are formed when four amino acids join together?

Chemists express the joining of these amino acids as follows:

Val + Thr + Ala + Gly → Protein and water

ANALYSIS QUESTIONS:

Name the three categories of carbohydrates studied in this investigation.

49. _______________________ 50. ________________________ 51._________________

52. What three elements are found in carbohydrates, fats, and proteins?

Give the names of the three monosaccharides studied

53. _______________________ 54. ________________________ 55._________________

Give the names of the two disaccharides constructed.

56. _______________________ 57. ________________________

58. What polysaccharide did you make?

59. What sugars combine to form disaccharides and polysaccharides?

60. The word carbohydrate is derived from the words carbon and water.Explain why this appropriate.

List two ways that fatty acids have a different composition and group than glycerol.

61.

62.

63. What group does fatty acids and amino acids have in common?

64. What small molecule is needed to make a large protein molecule?

What two groups do all amino acids have in common?

65.

66.

67. How do you make different proteins?

Color Code Instructions: LipidsGlycerol: brownFatty Acids: each a different shade of greens

Color Code Instructions: ProtiensAmino Acids: each a different shade of purples

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Blue-OH Ends-H Ends

Color Code Instructions: CarbohydratesGlucose: RedFructose: OrangeGalactose: yellow

Blue-OH Ends-H Ends