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

Explain adverse effects of ribavirin, Adverse Effects of Ribavirin  Sys...

Adverse Effects of Ribavirin  Systemic ribavirin has been associated with hemolytic anemia. Oral ribavirin plus interferon appears to cause a higher incidence of cough, pruritu

What are the hormones secreted by the neurohypophysis, Q. What are the horm...

Q. What are the hormones secreted by the neurohypophysis? What are their respective functions? The neurohypophysis secretes the antidiuretic hormone (ADH) and oxytocin. Oxytoci

What are respiratory pigments, Q. What are respiratory pigments? What is th...

Q. What are respiratory pigments? What is the respiratory pigment present in some arthropods? Which is the analogous molecule in humans? Respiratory pigments are molecules able

Define characteristic of doppler echocardiographic, Q. Define characteristi...

Q. Define characteristic of Doppler Echocardiographic? Ans. Doppler findings of cardiac tarnponade are based on the following characteristic respiratory variations in intr

Porifera, method of digestion in porifera

method of digestion in porifera

What are the classification of diabetes, Q. What are the Classification of ...

Q. What are the Classification of Diabetes? Several forms of diabetes have been identified as a result of research and survey conducted world-wide. These forms of diabetes incl

Define bioactive materials, Q. Define Bioactive materials? Bioactive ma...

Q. Define Bioactive materials? Bioactive materials: Certain glasses, ceramics, and glass-ceramics that contain oxides of silicon, sodium, calcium and phosphorus (SiO 2 , Na 2

Plants - slow moving waters, Plants - Slow Moving Waters Plant life is...

Plants - Slow Moving Waters Plant life is abundant in this habitat and includes rooted vascular plants such as pond weeds and grasses, firmly attached aquatic mosses and multi

What are other important human diseases caused by protozoans, What are othe...

What are other important human diseases caused by protozoans? Some other significant protozoan infections are amebiasis, trichomoniasis, giardiasis, leishmaniasis, toxoplasmosi

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