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

Infectious canine hepatitis, Infectious canine hepatitis The disease i...

Infectious canine hepatitis The disease is caused by type-1 canine Adenovirus in the family Adenoviridae. The disease appears in pups as peracute, acute, and mild. The clinica

Sulphur cycle - nutrient cycles, Sulphur Cycle - Nutrient Cycles The s...

Sulphur Cycle - Nutrient Cycles The sulphur cycle is mostly sedimentary except for a short gaseous phase. The large reservoir of sulphur is in the soil and sediment where it i

What are alternative medicines, Question 1: Differentiate between Tradi...

Question 1: Differentiate between Traditional, complementary and alternative medicines. Cite examples for each type. Definition of Traditional, alternative medicines and

Fat soluble vitamin needs of school children and adolescents, Determine Fat...

Determine Fat Soluble Vitamin Needs of school children and adolescents? ICMR (1990) does not give recommendations for vitamin D, E and K. Vitamin D is very important for skelet

How potassium dichromate dissolved in water, How would you prepare 90 ml of...

How would you prepare 90 ml of .01 M potassium dichromate dissolved in water? Molecular mass of potassium dichromate is 294 g/mol.

Anther dehiscence and pollen transfer, Anther Dehiscence and Pollen Transfe...

Anther Dehiscence and Pollen Transfer Anther Dehiscence Anther dehiscence simply means the release of pollen grains from dry and mature anthers. It involves the rupturi

Why is a leguminous crop rotation used in agriculture, Why is a leguminous ...

Why is a leguminous crop rotation used in agriculture? Leguminous crop rotation and other crop rotations are used in agriculture because in these plants many bacteria significa

Four characteristics of an efficient respiratory surface, State four charac...

State four characteristics of an efficient respiratory surface. Four characteristics of an well-organized respiratory surface are: a) thin epithelium, b) large surface ar

What is the embryonic development called, What are the cells produced in th...

What are the cells produced in the first stage of the embryonic development called? The cells that result from the cleavage (the first stage of the embryonic development) are k

Inadequate dietary intake - cause of anaemia is dietary, Define Inadequate ...

Define Inadequate Dietary Intake - cause of anaemia is dietary? The commonest cause of anaemia is dietary inadequacy of iron. The dietary intakes arc usually half of the recomm

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