Nervous System!

Parts of brain associated
with different senses

What does the brain do? That is the real question. It accomplishes so many things, it's hard to fathom. Your brain has a hard time figuring out what your brain does (ironic, right?). It is responsible for all of the motor responses to stimuli and has parts for speech, language recognition, smell, taste, and sight. Truly awesome. It tells everything in your body what do in a split second before it seems you have time to think, but your brain already noticed the stimulus, decided what to do, and responded to it. The brain does this via electrical impulses. Even though all of this information is known, scientist still have a lot to learn about the brain. They have learned most of what they know but studying brains that have gone wrong. By looking at the parts of the brain that have been affected by a disease, disorder, or damage, they can tell what the brain should be doing as opposed to what it is doing.
Cutting into a brain (as we did on Tuesday) all you see is bumps, ridges and white and gray matter. It doesn't seem like this matter can control everything you do, even involuntary functions like breathing, digestion, and pumping blood from the heart. That's what's so cool about it!
In the TED video, the neuroscientist, Dr. Taylor describes the events that unfolded after she had a stroke. She used to research mental illness, studying how cells and chemicals react in brains with schizophrenia and bipolar disorder. Then one morning she had a hemorrhage in her brain (a blood vessel exploded). Because of this she completely lost all control. She could not walk, talk, or remember everything from her past life. It's very interesting how one bursted blood vessel could affect all of this. This is in stark contrast to another part of the body. For example, in the arm, if a blood vessel were to burst, there would be pain, but it wouldn't lead to deterioration of function. The right and left hemispheres have different functions that map out every second of life by sensory information sucked in by the brain. The right hemisphere is very in the moment, like an adrenaline junkie. The left hemisphere is concerned with the past and future, thinking methodically and analytically. It organizes all of the obtained information into little filing cabinets and makes us individuals. The brain is an amazing, possibly the most amazing part of our body.

                        Check out this video, also from TED! It discusses the adolescent brain!
http://www.ted.com/talks/sarah_jayne_blakemore_the_mysterious_workings_of_the_adolescent_brain.html

Senses image from http://www.brainwaves.com

Three Questions! (November 23)

Playdoh Brain Model

Here's another installment of the weekly three questions. This week is special though, it's Thanksgiving break.
1. This was a short but awesome week in Anatomy. We first got to play with Playdoh again, something I haven't done in ten years. The playdoh brain helped us identify the structures and was fun to make, I must admit. Then, on Tuesday, we dissected a real sheep's brain which was way more cool than the playdoh brain. It really didn't smell that bad. I also went to Phoenix for the break to attend a concert and football game (against my will).
2. Lately I've learned most parts of the brain and the different functional areas. I've also learned how to do U substitution in calculus, and that Frankenstein's monsters isn't as bad as everyone thinks he is.
3. Next I plan to finish all the Nervous System coloring plates and finish reading Frankenstein. I also plan to get very familiar with the Nervous System for the test.

Playdoh Brain image from http://faculty.washington.edu/chudler/chmodel.html

Three Questions! (November 16)

Euler

1. Lately I have started the Nervous System in anatomy. I'm pretty excited that we get to dissect a sheep brain on tuesday! Also, I have started reading Frankenstein in english and took another test in calculus. I have a Phantom of the Opera concert friday and saturday night too. It's been pretty fun learning that music. The choir people are really awesome (shout out to Brad).
2. I learned a lot from the brain video we watched in anatomy. It was really interesting to see what happens if the brain is damaged. In math we're doing more integrals using things with slope fields and Euler's method. I also learned Euler's is pronounced Oiler's.
3. Next week I'm planning on working on the nervous system coloring plates and dissecting that brain! I'm also planning on taking a break from school during Thanksgiving Break (we're going to Phoenix).

Euler image from http://en.wikipedia.org/wiki/Leonhard_Euler

Neurophysiology Leech Lab

Leech opened
for dissection

The objective of this virtual neurophysiology lab was to record the electrical activity of individual neurons when mechanical stimulus is delivered through the skin of the leech. The we injected a fluorescent dye, called Lucifer Yellow, into the neurons the visualize their morphology.The cell was loacted  We identified the neurons based on their response to stimuli. First, we anesthetize the leeches so they won't move (not that they actually would in a virtual lab) and cut them open down the length of the leech. Then we carefully pinned the little guy down exposing its guts and connective tissue inward parts, we removed these parts, leaving the skin. The leech was put under the microscope and a segment was cut out to see the ganglia. Then we cut the sinus and used an electrode to locate a cell. A feather, probe and forceps were rubbed against the cell and the reaction (action potential) was measured. The three stimuli acted as light, medium, and strong stimuli. Lastly, we injected the fluorescent dye and viewed it under the UV light. With the UV light, the cell body, axons, and dendrites were visible.
The way that the cell reacted to the different stimuli demonstrated how there are different ways cells respond to levels of stimuli (light, medium, strong). The neurons can react differently because of their specific function or because of their environment. For example, neurons on your hand will react differently to neurons on your legs or face. Neuron classes are determined by their reaction to various stimuli.

Leech image from http://faculty.baruch.cuny.edu/jwahlert/bio1003/annelida.html
Giant Leeches image from http://philosophyofscienceportal.blogspot.com/2011_10_01_archive.html

Remote Controlling Life

This title may surprise you. Life is remote controlled only in science fiction! But sadly (or happily), you are mistaken. A scientist attached the motherboard of a remote controlled toy to a cockroach. He put the wires into the antennae of the cockroach and into its brain. So the Remote Controlled Cockroach was created. This can easily be seen as an ethical issue. Remote controlling life seems sort of wrong, but it doesn't seem so bad with an insect. But what about with a rabbit, a dog, or a human? Most people would immediately be repulsed at the idea of sticking a wire in someone's brain and sending electrical signals through them so that they can be controlled by a joystick. 

Man remote controlling another
person (Kind of looks like Mr. Gaume,
does it not?)

Before anyone goes rejecting or embracing an idea, we must think of the positive and negative aspects of such a thought. On the positive side, people that have been paralyzed by some unfortunate event could again walk. If this works, could the blind be coaxed to see again? Could the mute speak again? If an electrical signal can somehow bypass the damage inflicted upon the brain/ nerves during an accident, couldn't it stimulate a part that has been damaged, such as the visual cortex? Such ideas are fantastic if they did work, and were only used for ethical purposes? But what is ethicsAccording to Webster's Dictionary, ethics is "a set of moral principles". Most people would agree that certain things are right or wrong, and remote controlling a human being is one of those things. The negative side to this is as stated, the ethical implications. People controlling other people against their will is a frightening idea. The question is "who would decide who is remote controlled, who would have the ultimate power?". Power over life. In my opinion, this power shouldn't be designated to any human. 
In conclusion, this experiment was neat, and there will be a constant struggle over whether it is ethical. This could revolutionize science or maybe start a revolution. There is no clear cut answer and there will never be? 

Man remote controlling image from http://www.leadership-toolbox.com/autocratic-leadership.html
Video link from http://virtualgardnerblogs.weebly.com/anatomy--physiology.html

Three Questions! (November 9)

1. This week we finished the Muscular System in anatomy! All of the blogs, glogs, packets, and test are finally done! Such a relief! I also covered more about Integrals in Calculus and started reading Frankenstein in English.

Nervous System next week!

2. I have to admit I've learned a ton of stuff in anatomy while studying the muscular system. The physiology of a contraction is just amazing, and I think I've got origin and insertion down (even if all the thigh muscles seem to have the same ones). I also learned a lot in French this week. I'm getting much better at writing paragraphs.
3. Next week I need to finish and turn in my Macbeth essay. We're also starting the next system in anatomy, the nervous system I believe. I'm pretty excited about this one. There will undoubtedly be more glogs, blogs, and packets...again.

Nervous System image from http://www.getbodysmart.com/ap/nervoussystem/menu/menu.html

Three Questions! (November 2)

Orson Welles as Macbeth
circa 1948

Here's another installment of three questions! November 2nd edition. This is what I've done, learned, and hope to accomplish next week.
1. Lately I have worked on my muscular system packets and coloring plates.
2. This week I understood more of the muscular system microscopic anatomy after our class lecture/ discussion (more, please!). It's actually a really fascinating, yet cool process. In math, we started learning Integrals (whoo!), and in English I almost completed my essay on Macbeth. 
3.Next week I hope to finish the packets before the test and study for the Muscular System test. I will also do my glog on Fibromyalgia. Then I'll do some more studying and work on my online history class.

Orson Welles image from http://www.hollowaypages.com/welles.htm

Skeletal Muscle!

Diagram showing all the -mysiums and the fascicle

Skeletal Muscle is awesome! It allows us to run, smile, and give high fives. It's composed to hundreds to thousands of muscle cells, connective tissue wrappings, and blood vessels and nerves. Each cell spans the length of the muscle! Take the Sartorius, a very long muscle in the thigh region. This muscle can be a couple feet long, which is pretty crazy because most people thing of cells as tiny things. How does such a large cell survive, you ask? They are extremely skinny, perfectly suited to reside in our skeletal muscle. The cells are multinucleate and are thin enough for nutrients to get in and waste to be excreted. The cells are in bundles called Fascicles. In between the cells, also called fibers is the Endomysium. Perimysium surrounds the bundles, and Epimysium holds it all together on the outer surface. These three layers are essential in skeletal muscle; this type of muscle goes through a lot, pulling on the bone all the time. The reinforcement keeps the muscle from tearing, and possibly tearing off the bone if enough force is applied.

Arnold doesn't know how much
effort it takes his body to flex! 

The main goals of the muscular system include movement, heat generation, stabilizing joints, and maintaining posture. None of these would be possible without contraction. Did you know only one third of our muscle cells contract at any one time? If they all contracted, it would be too much force to handle and the muscle could rip from the bone!  The smallest unit of contraction in skeletal muscle is the sarcomere. In the sarcomere are the two proteins that facilitate contraction, called myofilaments. The myofilaments are called Myosin (thick filaments) and Actin (thin filaments). During contraction, the Actin slides towards the center of the sarcomere, pulling the edges of sarcomere (Z Plate) and shortening the cell. When all the cells contract together, movement is produced! Since we know that skeletal muscle is voluntary, you tell your arms, legs, and hands to move to perform a certain function. This seems like a long process, here's how it goes. You decide you want to raise you arm, so your brain sends an electrical signal to the muscle. This signal starts a chain of chemical reaction and uses some ATP to attach the Myosin and Actin. The Actin slides, and your arm moves. Then more ATP is used to relax your arm. This whole process took longer to read than it took to actually happen! This long, specific series of impulses and reactions took place without much though in a fraction of a second! Pretty amazing if you ask me!


Diagram image from http://people.eku.edu/ritchisong/301notes3.htm
Arnold image from http://www.maloneyperformance.com/Blog/?p=390