Biology: Life on Earth 6E Chapter 3 -- Destinations

Chapter 3: Biological Molecules
Destinations

The following Web sites are just some of the interesting resources related to the life of a cell. As you link to the sites, compare and contrast the information on the site with what you have learned in class, from the textbook, and from other sources you have read. Be sure to share interesting sites with your classmates.

1) Why Is Carbon So Important in Biological Molecules?

Aspirin: Click here to see the molecular structure of aspirin, an organic molecule most of us have some direct experience with. YouÕll be surprised at how simple the structure is!

Carbon Bonding Variations: This Web page provides a sampling of the astonishing array of bonding possible for carbon atoms.

Chemicals: Although this great Web site is aimed at middle school to high school students, the three-dimensional molecular structures it presents are informative and well organized. Use the link to look at molecular models.

Functional Groups: A comprehensive list of functional groups and their nomenclature can be found on this page.

Organic Compounds: Skip to the carbon section to start viewing a great series of lecture slides about carbon and its bonding properties. You may also want to go to the index and select other lectures to learn more about organic molecules, including alcohols, ethers, and acids. These lecture slides are very well done but go into chemistry in greater depth than is needed for introductory biology.

Organics in Outer Space: Scientists interested in the possibility of extraterrestrial life are constantly on the lookout for key molecular indicators, normally water and organic molecules. As this short news article points out, both have been found on Europa, one of Jupiter’s moons.

2) How Are Organic Molecules Synthesized?

Amino Acids: The 20 building blocks of proteins can be viewed at this site.

Amino Acids and Proteins: Go to this site to see animations that describe the molecular structure of amino acids and how they come together to form proteins.

Biomolecules: This site provides a good overview of organic molecules and the major types of biomolecules in cells.

Nucleotides: You will find great molecular models of nucleotides at this site. Check out the view from the top of a DNA double helix—it’s beautiful.

3) What Are Carbohydrates?

Carbohydrates: This site provides a good overview of carbohydrate structure and biochemistry.

Carbohydrates: A great series of lecture slides on sugars and other carbohydrates is presented at this site.

Sugars: You can view the three-dimensional structures of several sugar molecules at this site which is sometimes slow to load.

4) What Are Lipids?

Cholesterol: Cholesterol is a complex molecule needed for membrane function, but it can lead to heart disease if too much is present in the blood.

Prize for Cholesterol: Learn about Dorothy Hodgkin, whose analysis of molecules, including cholesterol, won the Nobel Prize for chemistry in 1964.

Lipids: You can view the three-dimensional structures of many lipid molecules at this site.

Milk: Have you ever wondered what kinds of molecules are in milk? Check out this site, particularly the links to milk lipids. These are what is removed from whole milk to make skim milk.

5) What Are Proteins?

Amino Acids: The structures of all 20 amino acids can be seen from this Web page.

Protein Structural Motifs: This site has illustrations of various secondary structure motifs commonly found in proteins. Click on the "mono" to see a single image. You can also download three-dimensional images but will need special goggles and a special program to view them.

Protein Structure: You can view animations of protein structure at this site.

6) What Are Nucleic Acids?

DNA Basics: This short but interesting site summarizes the basic features of DNA, including an interesting demo of how DNA coding can be so complex.

Nucleic Acids: Nucleic acid basics are given here.

DNA Discovery: This hyperlinked Web page gives an overview of the discovery of DNA structure by Watson and Crick.

DNA Structure: This site offers DNA animations and tutorials but you must download and install the Chime plugin.

Interactive DNA: This interactive exercise walks you through the basics of DNA structure. You will need software called PCMolecule or MacMolecule, which you can get free as a demo version from a link on this Web page.

Nucleic Acids: The overall structure of nucleotides in DNA and RNA can be viewed here.

RNA World: At this site, you will find links to molecular models and information about RNA (as well as links to information about DNA).