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Michael Dulay

Error Correction Activity: Sample


Exam: Section Two
The following essay contains several errors in its use and application of the material covered during this unit of the class.   Your task is to identify FIVE of these errors and correct them by clearly indicating the reasons for their misuse, as well as providing a correction to the error.   Your correction should be long enough to demonstrate that you understand the correct concept.

The Whole and it Parts

The human nervous system is responsible for most of the communication within the body.   It gives us the ability to read this essay, feel the cooling effects of the air conditioner in this classroom, and learn.   The system is divided first into a peripheral and a central system, with the primary distinction being that the parts of the central nervous system (i.e., brain and spine) are encased in bone.   The peripheral system, on the other hand, is extended into to the remainder of the body and it contains several subsystems.   Among these are the sympathetic and parasympathetic nervous systems, which give the body the ability to prepare for an emergency event and recover from one.   That is, the parasympathetic nervous system is the basis for the fight-or-flight response; and the sympathetic nervous system is the basis for the tend-and-befriend response. Although these responses are of astounding importance, the are overshadowed by the functioning and complexity of the central nervous system.

The human brain is made of 100 billion neurons.   Masses of neurons that have similar characteristics and functions are discrete brain parts.   In order to understand the complexity of the human nervous system, one must examine the major components of the brain.   Beginning at the base of the brain, the medulla is the structure that is responsible for maintaining a person's vital functions (e.g., heart beat, respiration, etc.).   The pons is a bridge that connects the structures in the lower brain (e.g., the medulla) and nervous system with higher brain structures.   It is tempered by the reticular formation(RF), a structure that regulates the influx of stimulation by acting like a "little net".   The RF, then, is the basis for human attention because it modulates the activity of the thalamus, which acts like a relay station for sensory information running into the brain.   The hypothalamus is responsible for regulating the functioning of the endocrine system, maintaining homeostasis, and orchestrating a person's vital basic behavior.   The limbic system is connected to the hypothalamus, and its structures are responsible for our ability to encode memories as well as experience emotion (i.e., rage and fear).   Above all is the structure that is responsible for our most complex functioning, the cerebral cortex.

Each neuron in the human body has several characteristics that distinguish it from other cells in the body.   The Dendrites are coated in a fatty material known as myelin, and they are responsible for receiving neural impulses.   Once electrical impulses are received from other neurons, neurotransmitters (NTs) are sent from the dendrites to the cell body.   In the cell body, receptor sites are activated by the NTs, which force an action potential down the axon so that it synapses with an difference neuron.   The entire action potential reflects a 100 mV rapid reversal of the cell's membrane potential.   In other words, a neuron moves from -70mV to +30mV within a couple milliseconds.  

There are many NTs involved in neural communication.   One of the most frequently studied and manipulated NTs is serotonin.   Because it is believed to modulate emotion, serotonin is the NT impacted by the most popular antidepressants on the market today.   Prozac, for example, decreases the availability of serotonin in the synapse by blocking reuptake.   It is also the NT that is impacted by illegal drugs, such as ecstasy and alcohol.   Other NTs of importance are acetylcholine, GABA, dopamine, norepinephrine, glia, and endorphins.

In sum, the nervous system is the basis for all communication within the human body, and it is made up of 100 billion cells called neurons.   These neurons lay in a mixture of neural tissue and blood in the brain.   They communicate electrochemically, using both NTs and ions to relay messages across small gaps called synapses.   In order to understand the complexity of human nature, one must examine the very smallest detail of the neuron.  


sample of student responses
NAME: _________________________

Instructions: IDENTIFY five (5) errors in the essay above by copying the sentence in which the error is contained.   Following the sentence, EXPLAIN why your selection is an error.   Lastly, CORRECT the error by rewriting the sentence so that it fits within the context of the entire essay.   Your correction should be long enough to demonstrate that you understand the correct concept.

Error ONE: The parasympathetic nervous system is the basis for the flight-or-fight response.

Reasons for error: The parasympathetic nervous system actually calms the body down after being involved in a flight-or-fight response. This system helps the body to slow down the heart rate and triggers the digestive system to work.

Correction: The sympathetic nervous system is the basis for the flight-or-fight response.

Reasons for the correction: The sympathetic nervous system helps the body to get ready for the fight-or-flight response. For example, it increases the heart rate, increases our inhalation and exhaustion rate, and prevents our digestion from working.

 

Error TWO: Dendrites are coated in a fatty material known as myelin.

Reasons for error: Axons are partially coated with myelin which helps the increase the speed of communication between neurons. Dendrites, on the other hand don't have such covering.

Correction: Axons are partially coated in a fatty material known as myelin.

Reasons for the correction: Axons are not completely covered by myelin sheaths. In fact, there are some uncovered areas on the axon which are not covered by myelin that are called Nodes of Ranvier. Action potentials jump between these Nodes of Ranvier which helps to speed up the communication speed between neurons.

 

Error THREE: Prozac decreases the availability of serotonin in the synapse by blocking reuptake

Reasons for error: What prozac actually does is that it increases the availability of serotonin in the synapse by blocking the reuptake.

Correction: Prozac increases the availability of serotonin in the synapse by blocking reuptake.

Reasons for the correction: When the prozac blocks the reuptake of serotonin in the synapse, the neurotransmitter ( serotonin) wouldn't have a chance to be reuptaken by the presynaptic neuron. What that does is that the serotonin stats accumulation in the synapse, which will eventually lead to an increase in its concentration.

 

Error FOUR: In the cell body, receptor sites are activated by the NT's, which force an action potential down the axon.

Reasons for error: There are receptor sites on post-synaptic neurons which will receive the neurotransmitters and that will cause them to form an action potential.

Correction: Once the action potential reaches the axon terminal, the neurotransmitters get releases into the synapse and the post-synaptic receptors will be activated by neurotransmitters.

Reasons for the correction: When post-synaptic receptors will be activated by neurotransmitters, the action potential will have a chance to get dispersed throughout different neurons in the body.

 

Error FIVE: Other NT of importance are acetylcholine, GABA, dopamine, norepinphrine, glia, and endorphins.

Reasons for error: Glia cells are some kind of nervous system cells which help neurons by providing structure, support, energy, and repair neurons when possible. Therefore, glias are not some for of neurotransmitters.

Correction: Other NT's of importance are acetylcholine, GABA, dopamine, norepinephrine, serotonin, and endorphins.

Reasons for the correction: Neurotransmitters help disperse the action potential between neurons in different parts of the body.

 


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