Category: Physiology
044 How Blood Flows Through the Heart
6.04K Views416 Comments21 Likes
How does the blood move around the body? What is the role of the heart in bringing blood to all the different parts of the body? Watch and see as Leslie gives an overview of the Circulatory System, the first in this ...
013 A Review of the Action Potential
2.14K Views231 Comments5 Likes
So we've gone over Depolarization, Repolarization and Hyperpolarization in some detail. It's time to do an overall review. Watch the video above to put everything into perspective and solidify your understanding. ...
043 The Details of Muscle Contraction
5.58K Views216 Comments15 Likes
Join Leslie as he shares this last video on muscle contraction explaining with full clarity the smallest details on how this works. Enjoy! Transcript of Today's Episode Hello and welcome to another episode of Int...
007 What is an Action Potential
2.69K Views208 Comments7 Likes
What is an Action Potential? That's the question I'm answering in todays Interactive Biology Episode. Watch the video above to find out ;) This is the first in my new video format and I really hope you enjoy it. ...
048 How to Read an Electrocardiogram (ECG/EKG)
13.06K Views188 Comments22 Likes
Have you seen an ECG reading? What do those lines mean? How does it measure heart activity? Watch and learn as Leslie once again teaches us about this topic. Enjoy! Transcript of Today's Episode Hello and welcome ...
052 The Cardiac Cycle
13.99K Views186 Comments53 Likes
Ever wonder what happens in a heartbeat? What happens inside our heart when we hear the 'lub-dub' sound? Watch and see as Leslie describes in full detail what a cardiac cycle is and how this is reflected in one heart...
037 How Sound is Transferred to the Inner Ear
2.24K Views148 Comments5 Likes
In this episode, Leslie talks about how sound is transferred to the inner ear. Because there is fluid inside the cochlea, impedance matching has to take place for the vibration in the fluid to accurately represent the...
009 Depolarization: Phase 1 of the Action Potential
4.02K Views145 Comments16 Likes
The action potential can be a complicated thing to understand, unless you are dealing with little white plusses on a table :) In this video, I help you visualize the first phase of the action potential - the Depolari...
011 Hyperpolarization: Last phase of the Action Potential
2.90K Views142 Comments5 Likes
First there's Depolarization, then Repolarization and finally - Hyperpolarization. Want to know what it's all about? Watch the video. It's only 2 minutes and 33 seconds, but it packs a punch. Any Questions or Comm...
045 The Pacemaker Potential of the SA Node and the AV Node
5.64K Views142 Comments11 Likes
In this episode, Leslie talks about how a pacemaker potential can cause a heart to beat automatically. Details about how it is generated is discussed in this video. Just how does this happen, our heart beating again a...
017 Two Types of Receptors
2.68K Views133 Comments4 Likes
After neurotransmitters are released from the cell, they bind to receptors on the next cell. In this video, Leslie explains how the two different types of receptors - the ionotropic and metabotropic receptors - work ...
042 How the Release of Calcium Ions Results in Muscle Contraction
5.11K Views131 Comments11 Likes
Now that you have an overview as to how muscle contraction works, here Leslie now discusses in more detail how it is affected in the presence of calcium. What really happens when these ions are released? Watch to lea...
049 What Stroke Volume is and How to Calculate It
3.53K Views121 Comments6 Likes
Stroke Volume = EDV - ESV What do these mean? Watch to learn more and understand about stroke volume. Enjoy! Transcript of Today's Episode Hello and welcome to another episode of Interactive-Biology TV where we’re...
008 The All-or-None Action Potential
1.50K Views119 Comments7 Likes
Ever wondered why people refer to the action potential as "all-or-none"? Well, I guess you'll just have to watch the video above to understand. In this video, I use the kitchen sink, a paper towel and marbles to brin...
060 Hemoglobin and the Oxygen-Dissociation Curve
4.38K Views119 Comments6 Likes
Ever wonder how the oxygen binds to our blood cells and sent to the different parts of our body? Watch and learn with Leslie as he explains how this happens and uses the Oxygen-Dissociation Curve to describe this even...
032 Visual Processing in the Retina
1.14K Views119 Comments4 Likes
After the rods and the cones, there are a few other important cells involved in visual processing. In this video, Leslie explains about how the bipolar cells and ganglion cells contribute to this process. Enjoy! T...
031 How Rods and Cones Respond to Light
1.50K Views117 Comments1 Likes
In this video, Leslie explains how rods and cones work, using the rods as an example. Watch to find out how rhodopsin, transducin, and phosphodiesterase, all play a major role in the process of vision. Enjoy! Tran...
019 What is Summation? (2 Types)
1.73K Views115 Comments3 Likes
When post-synaptic potentials reach the neuron, they can be added up through the process of summation. Watch as Leslie explains this process and expounds on the 2 types of summation. Enjoy! Transcript of Today'...
035 On Center, Off Surround Ganglion Cells
1.21K Views108 Comments1 Likes
In this episode, Leslie tells us about on center, off surround ganglion cells. See how the configuration of rods with respect to the ganglion cell's receptive field influences the type of response we get when those ro...
016 The release of Neurotransmitter
3.12K Views107 Comments1 Likes
When the action potential reaches the axon terminals, something needs to happen in order to transfer that signal from one neuron to another. Watch as Leslie explains the role of neurotransmitters and how their releas...
012 The Absolute and Relative Refractory Periods
4.03K Views104 Comments3 Likes
Refractory Period? What is that? If you are asking that question, then you want to watch this video. It explains why you can't stimulate another action potential at certain times regardless of how strong the stimulus...
023 How Reflexes Work (Knee Jerk and Eye Blink)
2.12K Views102 Comments2 Likes
In this video, Leslie's wife helps to demonstrate both the knee jerk and the eye blink reflexes. Watch as Leslie explains how both of these reflexes work. Enjoy! Transcript of Today's Episode Hello and welcome...
018 Agonists and Antagonists
2.00K Views100 Comments3 Likes
In this video, watch as Leslie explains how agonists and antagonists affect the receptor sites of the cell. Enjoy! Transcript of Today's Episode Hello and welcome to another episode of Interactive Biology TV, whe...
010 Repolarization: Phase 2 of the Action Potential
2.59K Views100 Comments5 Likes
Ok, so by now you should have an understanding of Depolarization: Phase 1 of the Action Potential. If not, then what are you doing here? Don't watch this video as yet. Check out the previous video first :) Now your r...
047 Action Potentials and Contraction in Cardiac Muscle Cells
6.33K Views100 Comments7 Likes
Leslie explains how action potentials are generated by the cardiac cells of the heart and how the release of calcium can generate heart contraction. Watch to learn more. Enjoy! Transcript of Today's Epi...
039 The Function of the Organ of Corti
2.37K Views99 Comments2 Likes
The organ of corti - such a small part of the cochlea with such a major function. Watch as Leslie demonstrates how the vibrations in the cochlea affect the cilia on the hair cells, and how this process is translated t...
022 Re: Akbar – Inactivation of V-gated Sodium Channels
767 Views98 Comments3 Likes
This is a video answering Akbar's question regarding the difference between the inactive and closed states of voltage-gated sodium channels. Watch as Leslie explains this difference using a box. Enjoy! Transcri...
024 Re: nicodube23 How Myelin sheaths Speed up the Action Potential
1.61K Views94 Comments3 Likes
In this video, Leslie clarifies how the myelin sheaths speed up the conduction of the action potential, in response to nicodube23's question posted on YouTube. Enjoy! Transcript of Today's Episode Hello and welco...
030 How Eyes Work – An Introduction
1.61K Views92 Comments3 Likes
In this video, Leslie explains all about how we are able to see with our eyes. Enjoy! Transcript of Today's Episode Hello and welcome to another episode of Interactive Biology TV, where we’re making biology fun! ...
038 How We Hear Different Pitches
1.69K Views91 Comments3 Likes
Some people sing high, others sing low. There are so many pitches, which are the result of different sound wave frequencies. How does the ear allow you to distinguish between these various pitches? Watch this video a...
033 The Receptive Field of a Ganglion Cell
848 Views88 Comments1 Likes
In this episode, Leslie explains more about the connections between rods and cones to bipolar cells, and between bipolar cells and ganglion cells. He also describes how these connections determine the receptive fields...
004 Ion Channels: The Proteins in the Membrane of Neurons
2.49K Views87 Comments7 Likes
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 neu...
014 The Journey down the Axon
1.60K Views85 Comments1 Likes
Why does the action potential travel in one direction down the axon? Why doesn't it go in reverse? Are there features about the axon that makes that happen? Watch the video and find out. Enjoy! - Leslie Samuel ...
034 How Lateral Inhibition Enhances Visual Edges
672 Views83 Comments3 Likes
In this video, Leslie explains all about lateral inhibition using two rectangles. Watch to learn how this process helps us see edges of objects more clearly. Enjoy! Transcript of Today's Episode Welcome to a...
062 Pressure Changes during Breathing
5.93K Views79 Comments9 Likes
Breathing is one of the most common things we do everyday to a point that it becomes unnoticed. Wouldn't it be great to learn what happens behind this process? What exactly happens when we breathe air in and out of ou...
054 Blood Pressure and Mean Arterial Pressure
4.68K Views76 Comments8 Likes
[DAP isPaidUser="Y" hasAccessTo="3" errMsgTemplate=""]…private…[/DAP] What does blood pressure really mean? What does it actually measure? Watch, listen, and learn as Leslie once again explains clearly and makes it...
058 Net Hydrostatic Pressure and Filtration Pressure
2.98K Views74 Comments4 Likes
How do the differences in hydrostatic and osmotic pressures affect the flow of blood within the circulatory system and to the different parts of the body? What is filtration pressure and how are these affected during ...
040 The Role of Hair Cells in Hearing
1.49K Views73 Comments1 Likes
Do you ever wonder what happens to the hair cells inside our ears as we hear sound? What role do these tiny hairs have in hearing? Watch this short movie as Leslie explains clearly and vividly enough for us to unders...
006 Donnan Equilibrium and Driving Force
1.40K Views70 Comments5 Likes
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 ...
046 How Adrenaline and Acetylcholine Affect Heart Rate
8.00K Views61 Comments8 Likes
In this episode, Leslie discusses the effect of adrenaline and acetylcholine on heart rate. These two modifies the conductance of the ions across the membranes of the cells of the SA node causing either an increase or...
001 An Introduction to the Nervous System
3.41K Views58 Comments7 Likes
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 Epis...
015 Saltatory Conduction
1.16K Views58 Comments4 Likes
The action potential travels rapidly down the axon. Why? Because of the process of saltatory conduction. In this video, I talk about how that process works. Question? Comments? Leave them below :) - Leslie Samu...
041 An Introduction to Skeletal Muscle Contraction
6.11K Views53 Comments10 Likes
Ever wonder how our muscles contract and what makes them do so? In this video, Leslie gives a clear overview of how muscle contraction works. Enjoy! Transcript of Today's Episode {Video begins with Leslie in a gy...
036 An Overview of the Mechanism of Hearing
1.26K Views53 Comments3 Likes
In this episode, Leslie talks about how we hear sounds. From the external ear to the eardrum, down to the 3 bony ossicles, then to the cochlea to be sent as signals towards the brain, it is all explained in this vide...
050 Regulating Stroke Volume, Skeletal Muscle Pump and Frank-Starling Mechanism
2.41K Views51 Comments2 Likes
Here, Leslie discusses how stroke volume can be regulated. Depending on which factors are changed, blood volume entering the heart may increase and in effect increasing heart contraction too. Watch, listen, and learn ...
026 The Function of the Cerebellum
2.55K Views49 Comments3 Likes
In this video, Leslie describes the cerebellum and explains how it's involved in coordination of movements. Enjoy! Transcript of Today's Episode Hello and welcome to another episode of Interactive Biology TV, whe...
025 The 4 Lobes of the Cerebrum and their Functions
4.00K Views48 Comments5 Likes
In this video, Leslie tells us about the cerebrum and the specific functions that each of its 4 lobes are responsible for. Enjoy! Transcript of Today's Episode Hello and welcome to another episode of Interactive Bi...
059 An Introduction to the Respiratory System
3.75K Views45 Comments6 Likes
We are off to start learning from a new set of videos about another part of the human body system and here, Leslie opens a new topic with a brief introduction of the Respiratory System. Watch and enjoy! Transcript...
027 The 3 Parts of the Brain Stem and their Functions
3.20K Views43 Comments4 Likes
In this video, Leslie explains about the different parts of the brain stem and their respective functions. Enjoy! Transcript of Today's Episode Hello and welcome to another episode of Interactive Biology TV, wher...
002 An Introduction to Neurons
2.72K Views43 Comments7 Likes
In this Episode, I give an Introduction to neurons. Since Neurons form the basis for the entire Nervous System, understanding what they are and what they do is essential. First I answer the question "What is a neuron...
