How should you use this blog?

Why these podcasts?

Biology is a science that covers complex concepts. One of the most challenging things for a biology student is to make sense of the central ideas and understand all the details.

It is important to focus on the essential information first; this allows you to build a foundation – or a skeleton – to which you can then add details. These podcasts are meant to help you master the essential concepts in college-level biology; they summarize the key points on the most important topics covered in an introductory biology course. Once you are familiar with these, then the details covered in class or in your textbook will become relevant (and will be much easier to learn).

How should you use the blog?

The podcasts are meant to be listened to while you look at the illustrations on this page. The visual content on the page really helps to make sense of the information. Also, listening to the podcast while you look at the related visual information on the screen stimulates your brain in several ways and makes it easier for you to really learn the essential concepts.

Should you be looking for more information (e.g., definitions), you can search external websites using the Google search toolbar provided in the right panel.

I hope you enjoy these podcasts, and that you will find them useful.

Essential Concept 1 : Organic Molecules

In this podcasts we summarize the structure and function of the four main classes of organic molecules found in living things:

1. Carbohydrates: sugars (e.g., glucose) and their polymers (e.g., starch and cellulose).

Structure:

Made of multiples of CH2O (e.g., glucose: C6H12O6)

Glucose, a monosaccharide (simple sugar)

Functions:

- Energy storage and processing (e.g., glucose, starch)

- Structure (e.g., cellulose)

- Cellular recognition

2. Lipids: a group of non-polar, hydrophobic molecules. 

Lipids include:

- Fats

Structure: 3 fatty acid attached to a glycerol backbone

An unsaturated fat composed of a glycerol backbone (left) and 3 fatty acids

Functions: energy storage, thermal insulation, mechanical protection of some organs

- Phospholipids

Structure: glycerol backbone + 2 fatty acids + phosphate group and variable hydrophilic group

A phospholipid

Functions: form the basic structure of biological membranes

- Steroids

Structure: 4 fused rings

Cholesterol, a steroid

Functions: stabilize membranes (cholesterol); some are hormones (e.g., estrogen, testosterone)

3. Proteins

Structure: chains of amino acids folded into a 3-D structure

An amino acid. The nature of the R group varies depending on the amino acid.

Functions: proteins are responsible for most of the work in living cells; e.g., structural support (e.g., collagen, keratin), movement (e.g., actin and myosin), transport (e.g., haemoglobin), catalysis of chemical reactions (enzymes).

4. Nucleic acids (DNA and RNA)

Structure: polymers of nucleotides; RNA is single-stranded, DNA is double-stranded due to complementary base pairing

A DNA nucleotide

Functions: storage and transfer of genetic information in cells. The information contained in genes (DNA) is used to make proteins, a process that requires different types of RNA molecules.


Keywords and Quiz coming soon!