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

What is the call frequency, During residency: This alters from program to p...

During residency: This alters from program to program depending on the number of sites covered and number of residents. At McMaster, we do call roughly 1 in 7 or 8 (averages out to

Determine about the diseases sleep attacks, Determine about the diseases Sl...

Determine about the diseases Sleep attacks These are brief, often irresistible, episodes of sleep, probably slow wave, NREM, naplike sleep that last about 15 minutes and can oc

Animal Respiration, What type of respiration does earthworm has ? In many c...

What type of respiration does earthworm has ? In many complex animals, the cells of internal organs are distant from the outside environment; respiratory systems provide the passag

What is the function of the plant cell wall, Q. What is the function of the...

Q. What is the function of the plant cell wall? The plant cell wall has protective and structural functions. It plays an significant role in the constraint of the cell size, pr

Why is blood significant for larger animals, What is the alternative means ...

What is the alternative means for transport of substances in animals without a circulatory system? Why is blood significant for larger animals? In animals that do not present t

Discuss in detail about the mitochondria, Discuss in detail about the Mitoc...

Discuss in detail about the Mitochondria An important function of the cell is to derive energy from the different oxidisable nutrients, such as, carbohydrates and fats supplied

What are main limitations on size that can be synthesized, What are main li...

What are main limitations on size that can be synthesized and how will that be change over next few years? A: Today, a 10kb gene or longer is built as part of the regular produ

Are the following statements true for eukaryotes, Are the following stateme...

Are the following statements true for eukaryotes , prokaryotes, both groups, or neither group? Answer They use a deoxyribonucleoside triphosphate as their energy currency"D They us

How can the visual deficiencies known as myopia, How can the visual deficie...

How can the visual deficiencies known as myopia and hypermetropia be optically explained? Myopia is the visual condition in which the images are produced before (in front of)

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