Biological Macromolecules

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Lab Report Assistant

This document is not meant to be a substitute for a formal laboratory report. The Lab Report Assistant is simply a summary of the experiment’s questions, diagrams if needed, and data tables that should be addressed in a formal lab report. The intent is to facilitate students’ writing of lab reports by providing this information in an editable file which can be sent to an instructor.

Exercise 1: Starch and Sugar

Data Table 1.Benedict’s Reagent Data.

Sample	Initial Color	Final Color	Reducing Sugar Present in Sample? Y or N
dH2O
Albumin
Unknown
Milk
Glucose

Data Table 2. Lugol’s Iodine Data.

Sample	Initial Color	Final Color	Starch Present in Sample? Y or N
dH2O
Albumin
Unknown
Milk
Starch
Raw Potato

Questions

A. In each of the two tests (starch and sugar) a positive and negative control was used. What was the positive control in each of the tests and what was the negative control. Explain your answers.

B. Did the Benedict’s test for reducing sugars net a positive or negative result for milk? Research the sugar content of milk and the definition of a reducing sugar to explain if your result is what you would expect.

C. Based on your results, is sugar and/or starch present in your Unknown? Use your results to explain your answer.

Exercise 2: Proteins and Lipids

Data Table 3. Biuret’s Reagent Data.

Sample	Initial Color	Intermediate Color	Final Color	Protein Present in Sample? Y or N
dH2O
Albumin
Unknown
Milk

Data Table 4. Lipid Observations.

Sample	Sample Observations	Lipid Present in Sample? Y or N
Distilled water
Albumin
Unknown
Milk
Vegetable oil

Questions

A. Review the Data Tables in Exercises 1 and 2. Compare the results of the Unknown for all tests to the results for the various known samples to determine the identity of the Unknown. Explain the identity of the Unknown using your experiment results in the exercises to help explain and support your answer.

B. Eggs are known to contain cholesterol which is a lipid. Did your experiment results indicate a presence of lipids in the albumin solution? Think about this result and where cholesterol is present in eggs to explain how your results support or reject cholesterol in eggs. How could you test this? Explain the experiment that you would perform to test this. Biological Macromolecules Lab Report

 

MORE INFO 

Biological Macromolecules

Introduction

The macromolecule is a complex molecule, typically consisting of hundreds or millions of atoms. It can be made up of different types of atoms (e.g., carbon, hydrogen and oxygen) in varying proportions.

Carbohydrates

Carbohydrates are organic compounds made up of carbon, hydrogen, and oxygen. They can be classified as monosaccharides, disaccharides, oligosaccharides or polysaccharides.

Monosaccharides are single-sugar molecules that contain one molecule of each element (such as glucose). The most common monosaccharide found in nature is fructose (common name: fruit sugar), which has two atoms of carbon and one atom each of nitrogen and oxygen.

Lipids

Lipids are a diverse group of compounds that include fats, waxes, sterols, fat-soluble vitamins, monoglycerides and diglycerides. They can be solids or liquids at room temperature. Lipids are not soluble in water but some are hydrophilic (they will dissolve in water).

Lipids are important for many cellular processes because they provide structural components for membranes and help transport things through the cell membrane.

Proteins

Proteins are large molecules that carry out functions in the body. They are made of long chains of amino acids, which can be joined together to form larger structures called polypeptides or proteins. Proteins perform functions such as transporting nutrients around your body, helping you digest food and clotting blood when you’re injured or sick.

Proteins are essential for life because they help build muscle tissue, regulate your heartbeat and blood pressure, create antibodies that fight off infections, produce hormones that control growth and development during pregnancy—you name it!

Nucleic Acids

Nucleic acids are complex molecules that contain genetic information in the form of DNA or RNA. The nucleotides found within each nucleic acid chain can be classified as either deoxyribonucleic acid (DNA) or ribonucleic acid (RNA).

In general, both DNA and RNA have a similar structure: A central sugar molecule is attached to phosphate groups, which are attached to the base monomers. The backbone of both strands is made up of alternating hydrophilic properties and lipophilic properties along their length; this gives them their unique properties when they are interacting with other molecules inside cells through interactions such as hydrogen bonding or van der Waals forces

Takeaway:

Biological macromolecules are the structural and functional building blocks of life. They’re made up of a combination of atoms or molecules, each bonded to others by covalent bonds. For example, carbohydrates (sugars) are composed of carbon, oxygen, hydrogen and nitrogen atoms; lipids are composed of fatty acids; proteins contain amino acids; nucleic acids include deoxyribonucleic acid (DNA) and ribonucleic acid (RNA).

In this section we’ll examine some examples of biological macromolecules:

Conclusion

I hope now you have a better understanding of what biological macromolecules are, how they work and how they can be used in different areas of science. You should also be able to see why each is important for our health and well-being as humans.