Enriched BiologyName______Date______

Organic Compounds Model Lab

Part One

You will receive a bag of models from your teacher. Be very careful when removing these models from the bag so they do not break. Each model has been labeled A-E. Models must be returned in the same condition as they are received or you will lose points off the lab.

Purpose of today’s activity is to have you hold and examine a specific organic monomer. The monomer you hold can be used to make a specific organic polymer or macromolecule that can be found in living things. Begin by reading the General Information below and then answer the questions about a specific model. Work as a team.

General Information:

White represents the atom hydrogen

Blue represents the atom oxygen

Red represents the atom nitrogen

Black represents the atom carbon

White tubing represents a covalent bond

Using the models, answer these general questions:

  1. How many covalent bonds does hydrogen make? ______
  2. How many covalent bonds does oxygen make? ______
  3. How many covalent bonds does nitrogen make? ______
  4. How many covalent bonds does carbon make? ______
  5. These compounds are considered organic because______

Questions for Model C, an Amino Acid

  1. How many carbon atoms are present in the compound? ______
  2. How many hydrogen atoms are present in the compound? ______
  3. How many oxygen atoms are present in the compound? ______
  4. Does this compound contain nitrogen? ______If yes, answer question #5-7. If no, go to question #8
  5. Locate the amino group on the model. What atoms make up this group? ______
  6. Since the compound has an amino group, it is an amino acid. Find carboxyl (acid) group. Can you find the double bond that connects a carbon atom to an oxygen atom? ______Identify the other atom bonded to that carbon? ______
  7. Amino acids are the building blocks for making a protein. Study the chemical reactions for making a protein.

Reaction #1 Amino Acid A + Amino Acid B  Dipeptide + H2O

Reaction #2 Dipeptide + Amino Acid C  Polypeptide + H2O

Reaction #3 Polypeptide + Amino Acid D  Polypeptide + H2O

a) What are the products of reaction #1? ______

b) What are the products of reaction #2?______

c)How are the polypeptide in Reaction #2 and #3 different? ______

  1. What is the ratio of hydrogen to oxygen atoms? ______(Use information from question #2 and #3)
  2. Is the ratio equal to 2 Hydrogens: 1 Oxygen atom? ______If yes, what type of organic compound is it? ______If is greater than 2H:1O, the compound you are looking at is a fatty acid which will be used to make a triglyceride. Triglycerides are organic macromolecules.

10. Model C can be used to make what type of organic polymer (macromolecule)? ______

Questions forModel A, a Monosaccharide:

  1. How many carbon atoms are present in the compound? ______
  2. How many hydrogen atoms are present in the compound? ______
  3. How many oxygen atoms are present in the compound? ______
  4. Does this compound contain nitrogen? ______If yes, answer question #5-7. If no, go to question #8
  5. Locate the amino group on the model. What atoms make up this group? ______
  6. Since the compound has an amino group, it is an amino acid. Find carboxyl (acid) group. Can you find the double bond that connects a carbon atom to an oxygen atom? ______Identify the other atom bonded to that carbon? ______
  7. Amino acids are the building blocks for making a protein. Study the chemical reactions for making a protein.

Reaction #1 Amino Acid A + Amino Acid B  Dipeptide + H2O

Reaction #2 Dipeptide + Amino Acid C  Polypeptide + H2O

Reaction #3 Polypeptide + Amino Acid D  Polypeptide + H2O

a) What are the products of reaction #1? ______

b) What are the products of reaction #2?______

c) How are the polypeptide in Reaction #2 and #3 different? ______

  1. What is the ratio of hydrogen to oxygen atoms? ______(Use information from question #2 and #3)
  2. Is the ratio equal to 2 Hydrogens:1 Oxygen atom? ______If yes, what type of organic compound is it? ______If is greater than 2H:1O, the compound you are looking at is a fatty acid which will be used to make a triglyceride. Triglycerides are organic macromolecules.
  3. Model A can be used to make what type of organic polymer (macromolecule)? ______

Questions forModel E, a Fatty Acid

  1. How many carbon atoms are present in the compound? ______
  2. How many hydrogen atoms are present in the compound? ______
  3. How many oxygen atoms are present in the compound? ______
  4. Does this compound contain nitrogen? ______If yes, answer question #5-7. If no, go to question #8
  5. Locate the amino group on the model. What atoms make up this group? ______
  6. Since the compound has an amino group, it is an amino acid. Find carboxyl (acid) group. Can you find the double bond that connects a carbon atom to an oxygen atom? ______Identify the other atom bonded to that carbon? ______
  7. Amino acids are the building blocks for making a protein. Study the chemical reactions for making a protein.

Reaction #1 Amino Acid A + Amino Acid B  Dipeptide + H2O

Reaction #2 Dipeptide + Amino Acid C  Polypeptide + H2O

Reaction #3 Polypeptide + Amino Acid D  Polypeptide + H2O

a) What are the products of reaction #1? ______

b) What are the products of reaction #2?______

c) How are the polypeptide in Reaction #2 and #3 different? ______

  1. What is the ratio of hydrogen to oxygen atoms? ______(Use information from question #2 and #3)
  2. Is the ratio equal to 2 Hydrogens:1 Oxygen atom? ______If yes, what type of organic compound is it? ______If is greater than 2H:1O, the compound you are looking at is a fatty acid which will be used to make a triglyceride. Triglycerides are organic macromolecules.
  3. Model C can be used to make what type of organic polymer (macromolecule)? ______

Questions forModel D, Mystery Monomer

1. Is it an organic compound? ______

2. What atoms are covalently bonded together? ______

3. Use the “Ratio Rule” to determine if it is a carbohydrate. Is it a carbohydrate? ______Why? ______

______

Summary Questions:

1. Which model is used to make polysaccharides? ______

2. Which model is used to make polypeptides? ______

3. Which model is used to make a disaccharide? ______

4. Which model is used to make a triglyceride? ______

5. Which model will Biuret Solution react with? ______

5. Which model represents water? ______

Now place all the models back in the bag. What is your Bag Number? ______Return the bag to your teacher. Continue working on this activity.

Part Two: Using Monosaccharaides to make Polysaccharides

Now that you know what a monosaccharide can look like. Let’s try putting two of them together to make a bigger molecule.

Carbohydrates are the source of energy for all living things. Carbohydrates are either considered “Simple” or “Complex”. Monosaccharide and disaccharides are the simple sugars because they are composed of one or two monomers. Polysaccharides are complex carbohydrates because they are made of many, many, monomers.

Glucose, fructose and sucrose are simple sugars. Starch is a complex carbohydrate. Use the paper strips to examine the structure of simple and complex carbohydrates. Follow this procedure. Answer the questions as you move along.

1. Study Figure 4. Find the glucose molecule. Color the glucose ring “red”.

2. On Figure 4, find the fructose molecule. Color the ring green. Now you have colored two different monosaccharides.

3. Take the strip and fold it to simulate a chemical reaction. After folding it, do you have a compound that is only red or only green? ______

4. Study the new compound. You have now formed sucrose which is common table sugar. Find the word ‘sucrose’ and color it red and green because it has parts of the glucose and fructose but circle it in blue because it is no longer glucose and fructose. A chemical change has occurred and made sucrose. Sucrose is a disaccharide because two monosaccharides were joined together.

5. Pick up Figure 5. You will make the complex carbohydrate, starch. Starch is stored energy for plants. You will join many monomers together.

6. Look for the glucoses on the strip. How many are there on the strip of paper? ______

7. Take the strip and fold it to simulate a chemical reaction to join the glucoses. How many times did you fold the paper strip? ______This represents the number of times a chemical reaction took place to make this segment of starch.

8. Look at your folded strip. Read the sentence on the bottom of the strip. How many glucoses are needed to make starch? ______

9. Look at the unmarked strip of paper. What monosaccharide is being used to make cellulose? ______Cellulose is found in the cell walls of plants.

10. Both cellulose and starch are the same because they are both made of glucose. However, they are different compounds because they have different shape. They use the same lego pieces but are arranged in a different structure.

Now you have completed both parts. Check to make sure that all the questions are completed by everyone in your group. Select the neatest copy. Place that copy on top and staple all papers together and place it in the designated bin.