Biology Structure of MacromoleculesName: _____________ Period: ___ Date:________For many years scientists believed that only organisms were able to synthesize the complex molecules needed for life. Since these molecules were found only in living organisms or the products of organisms, they were called organic macromolecules. Studies conducted by biologists and chemists have led to a greater understanding of these complex molecules and how they are produced.

Carbohydrates, proteins and lipids are the macromolecules that are of particular interest to scientists. They provide structure, biochemical control and energy for most organisms. In this activity you will examine the structure of these organic macromolecules.

OBJECTIVES: Identify the three elements founds in all carbohydrates and lipids, and the

four elements found in all proteins Describe the molecular structure of carbohydrates, lipids and proteins Visualize the structure of carbohydrates, lipids and protein by constructing

models

PART I CARBOHYDRATESCarbohydrates are macromolecules made up of monomers of simple sugars called monosaccharides.

A. Examine the structure of the two monosaccharides below:

GLUCOSE FRUCTOSE

1. Name the three elements found in each monosaccharide.

_____________ _____________ _____________2. Count the number of atoms of each element found in glucose and

fructose. Use this information to write the molecular formula for each monosaccharide below.

Glucose: C__H__O__ Fructose: C__H__O__

B. CARBOHYDRATE MODEL

Biology Structure of MacromoleculesName: _____________ Period: ___ Date:________You will create a simple carbohydrate by joining two monomers of monosaccharides.

1. Cut out two glucose models from the organic molecules model paper. Be sure to cut along the solid lines! Try to join the monosaccharides. Do they join easily like puzzle pieces? Explain.

2. Cut along the dotted lines to remove an H from one model and an OH from the other. Try to join the monosaccharides and glue them below

3. Can you create a new molecule by joining the H and OH pieces? Glue it below. Name the molecule that you formed.

4. What is this type of chemical reaction called?

PART II LIPIDSLipids are macromolecules made up of monomers of glycerol and fatty acids. There are many different fatty acids. Below is the structure of butyric acid, one example of a fatty acid. Some common lipids include oils, fats and waxes.

A. Examine the structure of the glycerol and fatty acids molecules below:

GLYCEROL BUTYRIC ACID

1. Name the three elements found in the glycerol and fatty acid molecules above.

_____________ _____________ _____________

Biology Structure of MacromoleculesName: _____________ Period: ___ Date:________2. Count the number of atoms of each element found in glucose and fructose. Use this information to write the molecular formula for each molecule below.

Glycerol: C__H__O__ Butyric Acid: C__H__O__B. LIPID MODELYou will create a simple lipid molecule called a triglyceride by joining the glycerol and fatty acids monomers.

1. Cut out the glycerol, butyric acid, stearic acid, and palmitic acid models from the organic molecules model paper. Be sure to cut along the solid lines! Try to join the glycerol and fatty acid molecules like puzzle pieces. Do they join easily? Explain.

2. What step is necessary before joining the glycerol and fatty acid molecules? (Think of what needed to be done in order to join the monosaccharides.)

3. Complete this step to create the lipid and glue below.

4. What molecule is formed by joining the H and OH pieces? Glue it below. How many molecules are formed?

5. What is this type of reaction called?

PART II PROTEINSProteins are macromolecules made up of monomers called amino acids. There are twenty amino acids found in living organisms. Different combinations of these twenty amino acids make up every protein!

Biology Structure of MacromoleculesName: _____________ Period: ___ Date:________A. Examine the structure of the two amino acids below:

GLYCINE ALANINE

1) Name the four elements found in each amino acid.

2) What element is found in proteins but not in carbohydrates or lipids?

3) Count the number of atoms of each element found in glycine and alanine. Use this information to write the molecular formula for each amino acid below.

Glycine: C__H__O__N__ Alanine: C__H__O__N__

4) The structure of every amino acid is very similar. Every amino acid consists of a central carbon atom bonded to a single hydrogen atom and three characteristic “groups.” Reexamine the glycine and alanine molecules shown below.a) An amino group (NH2) is found in every amino acid. Put a square

around the amino group (NH2) in glycine and alanine.b) A carboxylic acid group (COOH) is found in every amino acid. Put a

circle around the carboxylic acid group (COOH) in glycine and alanine.c) The third group consists of a variety of different atoms. This is the group

that makes one amino acid different from another. This group is called the “R” group. In the glycine molecule the “R” group is a single H. In the alanine molecule the “R” group is CH3. Place a triangle around the “R” groups of glycine and alanine.

GLYCINE ALANINE

B. PROTEIN MODELYou will create a simple protein molecule by joining the two amino acids.

1. Cut out the glycine and alanine models from the organic molecules model paper. Be sure to cut along the solid lines! Try to join the glycine and alanine molecules like puzzle pieces. Do they join easily? Explain.

Biology Structure of MacromoleculesName: _____________ Period: ___ Date:________

2. What step is necessary before joining the amino acids?

3. Complete this step to create the protein. Glue your protein here.

4. What molecule is formed by joining the H and OH pieces? Glue it here!

5. What is this type of reaction called?

Analysis:Fill in the venn diagram about what this activity told you about Proteins, Lipids and Carbs. Include info about their structure and how they bond together

Carbs Lipids

Proteins

ORGANIC MOLECULES MODEL PAPER

CARBOHYDRATE MODEL PROTEIN MODEL

Biology Structure of MacromoleculesName: _____________ Period: ___ Date:________

LIPID MODEL