BIOCHEMISTRY WS #1
WATER:
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 H 2O. 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:
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 ________
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.
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?
1.
What are the elements that are present in glucose, fructose, and galactose?
B. Disaccharides (double molecule sugars)
2. How many carbon atoms are present in a molecule of:
a. glucose _________
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?
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.
11. Do they easily fit together to form maltose?
12. What must be removed in order for them to fit together?
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.
13. What must be removed from the glucose molecules in order for them to fit
together?
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 _______________
21. List any similarities between glycerol and fatty acids.
BIOCHEMISTRY WS #2
A fat molecule consists of one glycerol and three fatty acid molecules joined together.
FATS:
Cut out the glycerol and fatty acid paper models. Cut along the solid lines only. Construct a fat molecule.
(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:
22. 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.
Examine the structural formula of glycerol.
23. How many fatty acid molecules are needed to form a fat molecule?
14. What elements are present in glycerol?
15. Are there any elements in glycerol that are not in carbohydrates?
16. 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.
17. What elements are present in all fatty acids?
18. What is the molecular formula for butyric fatty acid?
19. What is the molecular formula for lauric fatty acid?
20. What is the molecular formula for caproic fatty acid?
Join the all the left over OH and H ends to form a molecule. Place them on your unlined paper. Label it.
24. What chemical substance is formed when the OH and H ends are joined?
Name _______________________________ Block ____________ Date _______________
Another end arrangement in all amino acids consists of a Nitrogen atom and two Hydrogen atoms. This
group is called an amino group.
BIOCHEMISTRY #3
PROTEINS:
(Color the molecules involved with carbohydrates according to the color code.)
29. Do all structural formulas of amino acids have the amino group?
Proteins are complex molecules made up of simpler building blocks called amino acids. Examine the
structural formulas of the four amino acids shown below.
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.
30. 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.
31. 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
The element Nitrogen (N) is present in amino acids.
25. Is Nitrogen present in fats and carbohydrates?
26. What is the molecular formula for the amino acid glycine?
27. What is the molecular formula for the amino acid alanine?
28. What is the molecular formula for the amino acid threonine?
29. Are all the molecular formulas for all amino acids the same?
ANALYSIS QUESTIONS:
Name the three categories of carbohydrates studied in this investigation.
1. _______________________ 2. ________________________ 3._________________
4. What three elements are found in carbohydrates, fats, and proteins?
Give the names of the three monosaccharides studied
5. _______________________ 6. ________________________ 7._________________
Give the names of the two disaccharides constructed.
8. _______________________ 9. ________________________
10. What polysaccharide did you make?
11. 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.
12.
13.
What two groups do all amino acids have in common?
13.
14.
15. How do you make different proteins?
Color Code Instructions: Proteins
Amino Acids: each a different shade
of purples
_
Color Code Instructions: Lipids
Glycerol: brown
Fatty Acids: each a different shade of
greens
Blue
-OH Ends
-H Ends
Color Code Instructions: Carbohydrates
Glucose: Red
Fructose: Orange
Galactose: yellow
Blue
-OH Ends
-H Ends