Interactive Biology, by Leslie Samuel

Donnan Equilibrium? Driving Force? What in the world do those things mean? Well, you’re about to find out. In this video I explain the concept of Donnan equilibrium and show how that leads to the Driving Force that’s responsible for generating an Action Potential, otherwise known as the Nerve Impulse. If you want to know even more details about Donnan Equilibrium, check out my Notes on the Nervous System.

In this video, I talk about the isoelectric points of the proteins inside the neuron and how that results in the proteins having a negative charge. Understanding the negative charge of proteins inside the cell is important to understanding how neurons function. In the video, I also talk about the pH inside the cell. Just as a brief reminder, the pH tells how acidic or basic a solution is. If you need more info on pH, check out what Wikipedia has to say about pH.

There are 4 important classes of proteins in the membrane of neurons: Passive/Leakage ion channels, Sodium-Potassium pumps, Voltage-gated ion channels, and Ligand-gated ion channels. In order to understand how the neuron functions, we have to understand how those channels work. Watch the following video to learn about these proteins.

In this Episode, I talk about what Adenosine Triphosphate (ATP) is and how it works. ATP is the energy currency of the body and it provides energy when the third phosphate detaches from the the rest of the molecule, leaving Adenosine Disphosphate (ADP) behind. Many of the processes that happen in the cell require energy, and ATP provides that much needed energy. It’s what makes it so that you can run, talk, play sports and even just relax with a love one in the park

In this Episode, I give an Introduction to neurons. First I answer the question “What is a neuron?”. Then I go into the parts of a neuron. Lastly, I talk about the three types of neurons. Enjoy!

This is the first in my series of BioVid Episodes: Video Tutorials to help with Biology. In the first section of my BioVid Tutorials, I will be dealing with The Nervous System. To start it all off, in this BioVid Episode, I give an introduction to the Nervous System. First, I answer the question “What is The Nervous System?”. Then I a talk about the two divisions of the Nervous System:

First off, lets talk about what respiration is. In order for you to live, your body needs oxygen. Cells use this oxygen in order for metabolism to take place and without it, you would have no energy. When you eat, that food is broken down and the process of respiration allows for you to convert that food into an energy form that can be used by your body.

The functions of neurons depend on the movement of ions across the membrane. This happens both passively and actively across the membrane of a neuron. Lets talk about the passive process first. There are 2 factors that control the passive movement of ions across the membrane. Those 2 factors are diffusion and charge.

We’ve all heard the statement that “drugs kill brain cells”, but what about alcohol? Does the same thing apply? Does alcohol kill brain cells, and is that why we shouldn’t go out binging on a ton of alcohol?

First lets talk a little about how the brain functions. It’s estimated that there are over 100 billion brain cells (neurons) in the human brain. These cells are unique in that they can communicate very quickly with each other by sending nerve impulses, also known as action potentials. When the nerve impulse reaches the end of the axon, the axon terminals release neurotransmitters which then relays the signal to the next cell.

In order to have a full understanding of HOW neurons function, we have to take a look at the proteins that are in the membrane. These proteins play a significant part in determining the function of neurons. So, lets dive right in . . .