The article covered is "How Do Nerves Activate Muscle: Chemical Signals from Nerve Open Ion Channels in Skeletal Muscle" by Rosen, (2008). The world we live in today is driven by science and technology. Of course, the importance of these two cannot be over emphasized especially on the role they play in as far as to date development is concern.
Science has contributed negatively to the to the well being of mankind and life in general, for example; some chemicals have contributed significantly to pollution, some form of cancer have science to blame. This piece of work will try to analyze an article to help demonstrate one of the above aspects of science.
This article shows how nerves activate muscle. The nerve falls under the nervous tissues which are responsible for transmitting messages within the body while the muscle works to produce force that cause motion in the body organs (Rosen, para.2). The movement of the skeletal muscle is aided by a chemical released by the motor nerves called acetylcholine. The whole process of muscle contraction (which in essence is muscle movement) is as a result of ionic flux. Acetylcholine receptors within the muscle membrane is activated by acetylcholine which leads to exchange of positively charged and negatively charged ions(ionic flux) between the inside and the outside of the muscle cell.
As a result there is created a potential difference in the muscle membrane which opens another ion channel that transmits a nerve's signal all the way through to this membrane leading to contraction. Acetylcholine acts as the neurotransmitter in all the vertebrates' skeletal muscles. These muscles have nicotinic acetylcholine receptors (nAChR) lined up in their membrane from motor nerve to neuromuscular junction. nAChR is made up of five protein which interact to make a network which the ions can move.
Cells have small voltage across membrane. However, movement of ions in and out of the membrane as those caused by nicotinic acetylcholine receptor leads to changes in membrane voltage. This in turn sees the activation of sodium channels that disseminate electrical activation of the muscle, a process known as action potential. On reaching certain structures of the muscle cell action potential induces calcium ions. When these calcium ions are stimulated by changes in membrane voltage, activation of ryanodine receptors (calcium ion channels) occurs. This leads to release of calcium from their storehouses and its increase triggers changes in protein that will be responsible contraction of muscle fibers. Sequence of events thereafter leads relaxation of actin and myosin hence muscle contraction.
After the contraction, the calcium ions are actively bumped from skeletal muscles to there storage houses in the cell. The process is made possible by another calcium ion channel, different from that sees the release of the calcium. Once the calcium is pumped back the contraction of the actin and myosin relax leading to muscle relaxation. The importance of all the above channels cannot be over emphasized, without which serious disorders may arise. Myasthenia gravis, a condition that leads to muscle weakness results from development antibodies that targets the acetylcholine receptors.
In conclusion, this article tries to relate the interdependent and interconnection of different tissues, i.e the muscle and the nervous tissues and how they work to support life. Membrane transport which entails the movement of ions across the membrane has been shown. None of these ion channel is less important, and distortion of and distortion of any may result to certain disorders and diseases. It is therefore imperative to note that without proper interaction between independent cells, tissues, organs and systems then our bodies won't be able to function effectively.