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7
167

Visual Processing in the Retina

In this episode, I talk about the visual processing that happens in the retina, starting with the rods and cones, going to the bipolar cells and then the ganglion cells. Watch to learn how this process works.  
YouTube
almost 8 years ago
Preview
7
184

The Receptive Field of a Ganglion Cell

In this episode, I talk about receptive field of ganglion cells, showing how rods and cones are connected to bipolar cells that are then connected to Ganglion cells.  
YouTube
almost 8 years ago
Preview
7
232

Haematology - Red Blood Cells

https://www.facebook.com/ArmandoHasudungan Support me: http://www.patreon.com/armando Instagram: http://instagram.com/armandohasudungan Twitter: https://twit...  
YouTube
almost 7 years ago
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7
348

Monkey See, Monkey Do.

So you're sitting in a bus when you see a baby smile sunnily and gurgle at his mother. Your automatic response? You smile too. You're jogging in the park, when you see a guy trip over his shoelaces and fall while running. Your knee jerk reaction? You wince. Even though you're completely fine and unscathed yourself. Or, to give a more dramatic example; you're watching Titanic for the umpteenth time and as you witness Jack and Rose's final moments together, you automatically reach for a tissue and wipe your tears in whole hearted sympathy ( and maybe blow your nose loudly, if you're an unattractive crier like yours truly). And here the question arises- why? Why do we experience the above mentioned responses to situations that have nothing to do with us directly? As mere passive observers, what makes us respond at gut level to someone else's happiness or pain, delight or excitement, disgust or fear? In other words, where is this instinctive response to other people's feelings and actions that we call empathy coming from? Science believes it may have discovered the answer- mirror neurons. In the early 1990s, a group of scientists (I won't bore you with the details of who, when and where) were performing experiments on a bunch of macaque monkeys, using electrodes attached to their brains. Quite by accident, it was discovered that when the monkey saw a scientist holding up a peanut, it fired off the same motor neurons in its brain that would fire when the monkey held up a peanut itself. And that wasn't all. Interestingly, they also found that these motor neurons were very specific in their actions. A mirror neuron that fired when the monkey grasped a peanut would also fire only when the experimenter grasped a peanut, while a neuron that fired when the monkey put a peanut in its mouth would also fire only when the experimenter put a peanut in his own mouth. These motor neurons came to be dubbed as 'mirror neurons'. It was a small leap from monkeys to humans. And with the discovery of a similar, if not identical mirror neuron system in humans, the studies, hypotheses and theories continue to build. The strange thing is that mirror neurons seem specially designed to respond to actions with clear goals- whether these actions reach us through sight, sound, smell etc, it doesn't matter. A quick example- the same mirror neurons will fire when we hop on one leg, see someone hopping, hear someone hopping or hear or read the word 'hop'. But they will NOT respond to meaningless gestures, random or pointless sounds etc. Instead they may well be understanding the intentions behind the related action. This has led to a very important hypothesis- the 'action understanding' ability of mirror neurons. Before the discovery of mirror neurons, scientists believed our ability to understand each other, to interpret and respond to another's feeling or actions was the result of a logical thought process and deduction. However, if this 'action understanding' hypothesis is proved right, then it would mean that we respond to each other by feeling, instead of thinking. For instance, if someone smiles at you, it automatically fires up your mirror neurons for smiling. They 'understand the action' and induce the same sensation within you that is associated with smiling. You don't have to think about what the other person intends by this gesture. Your smile flows thoughtlessly and effortlessly in return. Which brings us to yet another important curve- if mirror neurons are helping us to decode facial expressions and actions, then it stands to reason that those gifted people who are better at such complex social interpretations must be having a more active mirror neuron system.(Imagine your mom's strained smile coupled with the glint in her eye after you've just thrown a temper tantrum in front of a roomful of people...it promises dire retribution my friends. Trust me.) Then does this mean that people suffering from disorders such as autism (where social interactions are difficult) have a dysfunctional or less than perfect mirror neuron system in some way? Some scientists believe it to be so. They call it the 'broken mirror hypothesis', where they claim that malfunctioning mirror neurons may be responsible for an autistic individual's inability to understand the intention behind other people's gestures or expressions. Such people may be able to correctly identify an emotion on someone's face, but they wouldn't understand it's significance. From observing other people, they don't know what it feels like to be sad, angry, surprised or scared. However, the jury is still out on this one folks. The broken mirror hypothesis has been questioned by others who are still skeptical about the very existence of these wonder neurons, or just how it is that these neurons alone suffered such a developmental hit when the rest of the autistic brain is working just dandy? Other scientists argue that while mirror neurons may help your brain to understand a concept, they may not necessarily ENCODE that concept. For instance, babies understand the meaning behind many actions without having the motor ability to perform them. If this is true, then an autistic person's mirror neurons are perfectly fine...they were just never responsible for his lack of empathy in the first place. Slightly confused? Curious to find out more about these wunderkinds of the human brain? Join the club. Whether you're an passionate believer in these little fellas with their seemingly magical properties or still skeptical, let me add to your growing interest with one parting shot- since imitation appears to be the primary function of mirror neurons, they might well be partly responsible for our cultural evolution! How, you ask? Well, since culture is passed down from one generation to another through sharing, observation followed by imitation, these neurons are at the forefront of our lifelong learning from those around us. Research has found that mirror neurons kick in at birth, with infants just a few minutes old sticking their tongues out at adults doing the same thing. So do these mirror neurons embody our humanity? Are they responsible for our ability to put ourselves in another person's shoes, to empathize and communicate our fellow human beings? That has yet to be determined. But after decades of research, one thing is for sure-these strange cells haven't yet ceased to amaze and we definitely haven't seen the last of them. To quote Alice in Wonderland, the tale keeps getting "curiouser and curiouser"!  
Huda Qadir
almost 8 years ago
Preview
7
260

Overview of the Immune System

This video gives a great overview of the cells and functions of the immune system in response to a pathogen.  
youtube.com
about 6 years ago
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6
79

Immunology - Innate Immunity (MHC processing)

Describes how Major Histocompatibility Complexes Class I and II presents itself on cell surfaces with Antigens.  
Nicole Chalmers
almost 8 years ago
Preview
6
151

Siddharthan Chandran: Can the damaged brain repair itself?

After a traumatic brain injury, it sometimes happens that the brain can repair itself, building new brain cells to replace damaged ones.  
YouTube
almost 8 years ago
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6
93

What are stem cells? How can they be used for medical benefit?

A short educational film by the Irish Stem Cell Foundation Stem cells are master cells of the body.  
YouTube
over 7 years ago
Canceroverview
6
178

The Biology of Cancer

The oldest descriptions of cancer were written in Egypt as early as 3000 B.C., as part of an ancient Egyptian textbook on surgery. The name, "cancer" comes from the Greek word carcinos, which means crab. Hippocrates used this term to describe the disease because of the projections of a cancer invading nearby tissues. During the 16th century, when the theory of bodily humors prevailed, it was believed that an excess of black bile caused cancer. The renowned anatomist Andreas Vesalius searched diligently for this black bile and ultimately discarded the this theory when he was unable to find it. In 1838 a botanist named Matthias Schleiden and Theodor Schwann, a physiologist, proposed that all living things were composed of fundamental units called cells. Shortly after the introduction of this idea, Virchow (the "father" of pathology) proposed that cells only arose from other cells and that growth could only occur as a result of hypertrophy or hyperplasia. Virchow studied cancers under with a microscope and recognized that they represented hyperplasia in an extreme form that he dubbed "neoplasia."  
sphweb.bumc.bu.edu
about 7 years ago
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6
133

Basic Medical Pathology: Morphological Expressions of Cell Injury

National Institutes of Health Lister Hill National Center for Biomedical Communications Basic Medical Pathology: Morphological Expressions of Cell Injury AVA...  
youtube.com
almost 7 years ago
Caduceus folk helix pedigree
6
121

Androgen insensitivity syndrome

Androgen insensitivity syndrome is a condition that affects sexual development before birth and during puberty. People with this condition are genetically male, with one X chromosome and one Y chromosome in each cell. Because their bodies are unable to respond to certain male sex hormones (called androgens), they may have mostly female sex characteristics or signs of both male and female sexual development.  
ghr.nlm.nih.gov
over 6 years ago
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6
270

Brains, Bodies, and Behavior

The nervous system is composed of more than 100 billion cells known as neurons . A neuron is a cell in the nervous system whose function it is to receive and transmit information . As you can see in Figure3.2, “Components of the Neuron” , neurons are made up of three major parts: a cell body, or soma , which contains the nucleus of the cell and keeps the cell alive ; a branching treelike fiber known as the dendrite , which collects information from other cells and sends the information to the soma ; and a long, segmented fiber known as the axon , which transmits information away from the cell body toward other neurons or to the muscles and glands .  
peoi.org
about 6 years ago
Preview
6
863

Chronic Kidney Disease | Clinical Gate

The kidney is one of the most highly differentiated organs in the body. At the conclusion of embryologic development, nearly 30 different cell types form a multitude of filtering capillaries and segmented nephrons enveloped by a dynamic interstitium. This cellular diversity modulates a variety of complex physiologic processes. Endocrine functions, the regulation of blood pressure and intraglomerular hemodynamics, solute and water transport, acid-base balance, and removal of drug metabolites are all accomplished by intricate mechanisms of renal response. This breadth of physiology hinges on the clever ingenuity of nephron architecture that evolved as complex organisms came out of water to live on land.  
clinicalgate.com
about 6 years ago
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6
124

Inner Life Of A Cell

A fantastic visualisation of the cell.  
youtube.com
almost 6 years ago
13
5
132

Cell Injury and Death

Struggling with Pathology? Why not join Howard Reisner, co-author of the bestselling Rubin’s Pathology, and Essentials of Rubin's Pathology, about Cell Injury and death. In it, he covers a variety of essential topics. For more information, or to purchase your copy of one of Dr Reisner’s books, visit [www.lww.co.uk](http://lww.co.uk). Save 15% (and get free P&P) on this, and a whole host of other [LWW titles](http://lww.co.uk) when you use the code MEDUCATION when you check out!  
Lippincott Williams & Wilkins
over 8 years ago
Preview
5
195

Renal Anatomy 3 - Glomerular Histology

http://www.handwrittentutorials.com - This is the third tutorial in the Renal Anatomy series. This video explores the histology of the glomerulus, and discusses the cell types. The juxtaglomerular apparatus is also discussed in detail. For more entirely FREE tutorials and their accompanying PDFs, visit http://www.handwrittentutorials.com  
HelpHippo.com
almost 8 years ago
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5
87

Renal Physiology (cont.)

Professor Saltzman continues his description of nephron anatomy, and the specific role of each part of the nephron in establishing concentration gradients to help in secretion and reabsorption of water, ions, nutrients and wastes. A number of molecular transport processes that produces urine from the initial ultra-filtrate, such as passive diffusion by concentration difference, osmosis, and active transport with sodium-potassium ATPase, are listed. Next, Professor Saltzman describes a method to measure glomerular filtration rate (GFR) using tracer molecule, inulin. He then talks about regulation of sodium, an important ion for cell signaling in the body, as an example to demonstrate the different ways in which nephrons maintain homeostasis.  
Nicole Chalmers
almost 8 years ago
Preview
5
79

Immunology - Innate Immunity (Diapedesis)

Describes the process how the immune cells move from the blood vessels to the surrounding tissues.  
Nicole Chalmers
almost 8 years ago
Preview
5
147

Poikilocytosis of RBC

This lecture covers images and important key terms for corresponding cell anomaly.  
MLS student Cez Alen Aguilar
almost 8 years ago