Neural circuits, Biology

Assignment Help:

Neural Circuits

The simple all are none activities of a single neuron can hardly provide the adaptability needed for the constant changes faced by the organism in its internal and external environments. Information about the external environment is integrated with signals arising within the organism and transmitted to effectors to elicit a coordinated response. Thus each neuron forms a unit in a communication circuit. A survey of the features of the nervous system in the animal groups at various points on the phylogenetic tree shows that a long evolutionary process has produced the outstanding complex structure of the human brain.

83_Neural Circuits.png

Figure: Nerve Net in Jelly Fish

Protozoans are single celled organisms and clearly cannot have a nervous system. An examination of the electrical properties of the protozoan cell membrane would, however, show many similarities to those of nerve cells including electrical potential changes and currents associated with activity. Coelenterates are of great interest neurologically since they are the first animals to possess a true nervous system. The coelenterate nervous system consists of a diffuse network of neurons that are distributed throughout the body wall. Such a simple and primitive nervous system is termed a nerve net in which neurons are dispersed mostly at random. Though primitive, this arrangement serves the need of a radially symmetrical animal whose food and enemies may approach from all directions. The animal's reaction depends on the strength of the stimulus. Only a part of the body reacts to a weak stimulus and a strong stimulus causes the entire animal to respond. From such diffuse primitively organised system of nerve cells, evolution has produced a complex organized nervous system such as that of man. The system of local nerve nets, however continues to exist even in many advanced invertebrate groups and in the intestines of vertebrates.


Related Discussions:- Neural circuits

Cardiac catheterization of mitral stenosis, Q. Cardiac Catheterization of m...

Q. Cardiac Catheterization of mitral stenosis? Cardiac catheterization is rarely needed to diagnose mitral stenosis. An end diastolic gradient more than 5 mm Hg. across mitral

Show the valve that separates the aorta from the heart, Q. What is the valv...

Q. What is the valve that separates the aorta from the heart? What is the importance of that valve? The valve between the aorta and the left ventricle is the aortic valve. The

Explain in brief about cytokines, Cytokines activate inflammatory cells lik...

Cytokines activate inflammatory cells like neutrophils and eosnophils.IL-5 is important in activation of eosnophils, IL-4 enhances IgE production by B-cells. IL-4, Il-5, IL-6, TNF-

Are there chloroplasts in cyanobacteria, Are there chloroplasts in cyanobac...

Are there chloroplasts in cyanobacteria? In cyanobacteria there are no chloroplasts and the chlorophyll layers are dispersed in cytosol. Which chemical element is central in

What are the uses of wpc, What are the uses of WPC?  Whey protein conce...

What are the uses of WPC?  Whey protein concentrates are used extensively in the manufacture of baked goods, where they enhance the effectiveness of shortening through better d

Briefly explain how amniocentesis used in genetic screening, Briefly explai...

Briefly explain how amniocentesis and chorionic villi sampling are used in genetic screening. A small sample is removed from the amniotic fluid surrounding the fetus or from t

Determine the function of iron for athletes, Determine the function of Iron...

Determine the function of Iron for athletes? Iron carries oxygen and is another important mineral for athletes. It also affects oxygen transport and aerobic metabolism as a com

Which process is called "reverse osmosis", When water containing impurities...

When water containing impurities is forced against a filter that allows only water through, this process is called "reverse osmosis". Why is this a good description of what is happ

Explain the process of absorption of fats, Explain the process of Absorptio...

Explain the process of Absorption of Fats? After digestion, only 25% of triglycerides are broken completely to glycerol and fatty acids. Major digestion product is 2-monoacylgl

Phylum protozoa, What are some examples of organisms belonging to this phyl...

What are some examples of organisms belonging to this phylum? Please name them.

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd