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1. Be able to label a diagram or a model of a human brain including the following parts: medulla, pons, cerebellum, midbrain, thalamus, hypothalamus, pituitary gland, and cerebrum. Tell briefly what each part does.
   Medulla - controls basic body functions such as breathing and heart rate.
   Pons - works with medulla to control heart rate and breathing (damage to this area is obviously serious).
   Cerebellum - is responsible for out balance and coordination.  It does so by comparing what our cerebrum tells our body to do with information coming from our muscles about what our body actually did, and them makes the appropriate adjustments.
   Midbrain - in humans this area does nothing more than relay information to higher centers in the brain. In birds this is an important area for vision.
   Thalamus - this is the switch board of the brain.  All information going to, or coming from the cerebrum is processed and/or routed through the thalamus.
   Hypothalamus - this controls our emotions and the release of hormones that control many body functions.
   Pituitary gland - produces and releases many hormones but is under the control of the hypothalamus.  Some of the hormones produced by the hypothalamus are released by the pituitary which is often called the "master gland".
   Cerebrum - this is the part of the brain where thinking, memory, consciousness, etc are performed.  This area is responsible for integrating all of the information coming in from our senses and then making decisions about how to respond.
    
2. What is a neuron? Draw a picture of a typical neuron and label it’s parts. Where does information enter a neuron and where does information leave from?
   The neuron is another name for an individual brain cell.  A typical neuron is illustrated on the patch for this honor.  There are approximately 200 billion neurons in the human brain.  No all of them look the same but most have the features listed below.  Neurons function by sending electrical signals through the brain so most of the parts of a neuron have a part to play in this process.
   Dendrites - receive electrical information and input from other neurons in the circuit
   Soma - this is the largest part of the neuron and is where are the usual part of a cell are found including the nucleus
   Nucleus - controls the activity of the neuron (all cell have a nucleus)
   Axon - the longest part of the cell and is able to conduct electrical signals from the dendrites to the terminals
   Schwann Cells - act as insulation of the electrical activity in the axon
   Terminals - these release a chemical signal that travels to the dendrites of the next neuron.
    
3. Explain how drugs affect the function of neurons especially at the ‘synapse’. Make a commitment never to take drugs except for medical reasons.
   The synapse is the "connection" that exists between individual neurons.  If one neuron is to send a signal to another neuron (this is how the brain works) then the first neuron releases a chemical signal (called a transmitter) from its terminals that moves to the second neuron and binds to its dendrite.  This leads to an electrical signal being produced in the second neuron.  Drugs do one of two things at a synapse.  Some (like nicotine from cigarette smoke) mimic the activity of the transmitter at the synapse and artificially stimulate the second neuron inappropriately (causing the strange sensations that are typical of a "trip" on drugs).
    
4. What is a reflex: Perform a knee-jerk reflex test on someone. (Instructions: Gently tap someone just below the knee-cap while the person’s leg is hanging over the edge of a chair.) Explain why it occurs (use the following terms in your answer: sensory neuron, motor neuron, spinal cord). Why do doctors use this test in a physical exam?
   A reflex is a behavior that occurs without the conscious use of your brain.  Sensory neurons respond to some stimulus in the environment, and their axons project to the spinal cord. There they synapse with motor neurons which send their axons to the muscle that cause their response. The response happens without the connection to the brain.  Later the brain will receive information from other neurons that tell it that the behavior occurred!  Doctors use this "knee-jerk" reflex as a quick check on how your sensory and motor neurons are doing.  Since you don't use your brain for this, you can't trick your doctor!
   
   Note: gentle taping on the tendon just below the knee-cap causes stretch sensitive sensory neurons to send signals (through the spinal cord) to motor neurons and muscles on the other side of the leg to tell those muscles contract and compensate for the stimulus.  Make sure that the patients' leg is dangling and not touching the floor. Some people response with a clear movement of the leg whereas others may only show a subtle "twitch".
    
5. What is a sensory neuron, and what is "adaptation".
   Sensory neurons are those neurons that respond to stimuli from the environment, such as those that respond to light, sound, touch, etc. Some of these neurons respond to the change in a stimulus and then their response decreases over time.  For example when you first smell a bad odor, you are really aware of it; but over time you "get used to it".  Adaptation is when a neuron no long responds to a stimulus even though the stimulus is still there.

Demonstrate adaptation by doing the following:
a.  Rest your arm on a table and then place a small cork (or something very light) on your arm. Notice how it feels at that time and how it feels one minute later after not moving.
It is important that the person does not move during the test.  The lighter the object the faster the neurons will adapt so 1 minute may not be necessary for the "feeling" to go away.  This is why, for example, we don't really notice the feeling of our clothes shortly after we have put them on or why the brightness of the sky in the winter does not seem to bother us once we have been outside for some time.

b.  Place one finger of one hand in a bowl of cool water and another finger of the other hand into a bowl of warm water. After 30 seconds, put both fingers in to a bowl of water a t room temperature. How does the water at room temperature feel on each finger?
Again this works best if the patient is not moving much during the experiment (especially the fingers).  Also it is better if the fingers being tested do not touch the bottom of sides of the bowls. As one finger adapts to the cold and the other to the warm water, they "notice" a change when placed in the water at room temperature.  The finger from the cool water feels warmer while the finger from the warm water feels colder in the water at room temperature!

c. What spiritual lesson can be drawn from the concept of adaptation?
One of Satan's most successful strategies is to get us so used to sin happening around us so that we don't even notice that we are getting involved.  If we don't now there is trouble around us that we don't seek the protection of God and the Devil has us trapped!
 

6. How are the senses of taste and smell similar and how are they different. Draw a map of which part of the tongue responds to the following tastes: sweet, sour, bitter, salt. Instructions: Have someone dip a Q-tip into one of the following: sugar water (for sweet), lemon Juice (for sour), flat tonic water (bitter) or salty water (salt), and then lightly touch different parts of your tongue. Notice which areas of the tongue taste the solution that is being tested. Rinse with pure water between each test and use a new Q-tip for each test.
   Taste is the sense that responds to chemicals dissolved in waters whereas smell is the sense that detects chemicals in the air.  Both work together so that the ability to taste is not as good when you nose is plugged (i.e. when you have a cold) and the ability to smell is not as good when your tongue is not working well (i.e. you burnt your tongue on some hot drink).
   
   Usually, taste buds for sweet are on the tip of the tongue.  Salt is detected on the sides.  Sour detectors are further back on the sides of the tongue and bitter detectors are on the very back.  No taste buds are found in the center - this is where pressure detectors are located which tell your tongue where the food is in your mouth.
   
   A trick for making this experiment work is to not put too much of the solution on the Q-tip so that the solution runs all over the tongue when you test it. Also, since lemon juice is a complex mixture of chemicals, it might activate taste buds that are not sensitive to sour (i.e. salt detectors on the tongue). Each taste that we can detect is determined by the relative amount of stimulation of sweet, sour, salt and bitter detectors.
    
7. Draw a picture of the various parts of the eye and explain why you have a blind-spot. Find your blind-spot for one eye. Instructions: Place a very small black dot on the center of a white piece of paper. Close on eye and stare directly ahead. Hold the paper at arms length in front of you and move the paper until the spot "disappears" (usually this is occurs when the dot is just a bit below eye level).
   In order for this to work, you must continue to stare straight ahead as you move the paper around in your field of view. Don not look directly at the dot on the page.  Also the dot must be small so as not to be bigger than your blind spot. Fortunately, the blind spot for each eye is slightly different, so the overlap of your two eyes normally compensates for each other.
    
8. Describe the three basic parts of the ear and tell what each part does.
   Outer ear:  This part funnels the sound waves onto the ear drum which vibrates according to the sound waves present.
   Middle ear:  The vibrations created by the ear drum are amplified by a series of small pivoting bones.
   Inner ear: The amplified vibrations are detected by very sensitive hair cells which send electrical signals to the brain by way of the sensory neurons.
   
   Explain why the following activities can be bad for your hearing:
   a.  listening to a "walkman" - too much sound over time can damage the sensitive hair cells in the inner ear which can cause permanent hearing loss.
   b.  putting something long in your ear - this could puncture ear drum
   c.  being in the front row at a loud music concert - same as above
   d.  not treating an ear infection properly - this can plug the tubes that lead from the middle ear to the back of your throat.  These tubes release pressure caused by the ear drum vibrations.  If there plug up, hearing is reduced.
   e.  standing behind a jet at an airport - this very loud sound can tear the ear drum as well as damage the hair cells of the inner ear
    

9. Do one or more of the following activities: (some of these activities will need to be planned with a medical/dental professional or at a local college or university – they are usually very willing to assist you)

1. Observe an electroencephalogram or one being performed on someone and describe what can be learned from this test.
2. Watch a "lie-detector" test being performed. Briefly explain how on works.
3. Observe an MRI or one being performed and explain what information and explain what information can be learned from such a test.
4. Observe a neuron under a microscope.
5. Observe someone receiving a local or general anesthetic and explain how a anesthetic works.
6. Observe a real human brain (fresh or preserved)
    

1.  Wear a helmet when participating in activities that require one such as: mountain biking, rock climbing, hockey, skate boarding, construction work, etc.
2.  Get plenty of fresh air. Oxygen is need by the very active neurons and if they don't get enough they die and cannot be replaced.
3.  Eat healthy food.  As your body is healthy so is your brain!
4.  Say NO to drugs.  Must drugs have harmful effects on your brain, many of which cannot be reversed.  Why take such a risk!
5.  Exercise your brain.  The more you use your brain the better it will work for you.  Learning is a lifetime experience.
6.  Avoid reading and watching material that is not consistent with Christian lifestyle. Over time all that input can effect the decisions that your brain makes.

11. Do one of the following:

1. Visit and help care for someone (minimum of 2 hrs) who has a disease of the nervous system and report on their special needs.
2. Briefly describe the following disorders of the nervous system:

Alzheimer's Disease - a fatal loss of brain function (particularly in the cerebrum) leading to severe memory loss.  The actual cause in not clear.
Multiple Sclerosis - a degeneration of the Schwann cells on the axons of neurons. This lack of insulation interrupts the electrical signaling and so a loss of control of muscles occurs.  This can lead to death when the neurons controlling breathing are affected.
Epilepsy - Uncontrolled "electrical storms" in the circuits in the brain.  These can be treated by drugs of sometimes by surgery.
Major Depression - Chemical imbalance in the brain such that some of the synapses in the brain are not able function properly.
Down Syndrome - A genetic disorder that leads to various levels of mental retardation.
Huntington's Disease - A genetic disorder that leads to premature death of cells in the brain.
Quadriplegic - Someone who has suffered spinal cord injury that has caused the loss of use of both arms and legs.  The damage must have been in the neck area so that information between the arms and legs and the brain is blocked.
Paraplegic - Someone who has suffered spinal cord injury that has caused the loss of use of both legs. The damage must have been in the back area so that information between the legs and the brain is blocked.
 

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