Explain about cerebral hemispheres, Biology

Assignment Help:

How is it structurally explained that the motor activity of the left side of the body is controlled by the right cerebral hemisphere and the motor activity of the right side of the body is controlled by the left cerebral hemisphere?

In the cerebral hemispheres there are neurons that centrally command and control muscle movements. These neurons are known as superior motor neurons and they are located in a special gyrus of both frontal lobes called as motor gyrus (or precentral gyrus). The superior motor neurons send axons that transmit impulses to the inferior motor neurons of the spinal cord (for neck, trunk and limb movements) and to the motor nuclei of the cranial nerves (for face, eyes and mouth movements).

The fibers cross to the other side in exact areas of those axon paths. About 2/3 of the fibers that go down the spinal cord cross at the medullar level forming a structure known as pyramidal decussation. The other (1/3) of fibers descend in the same side of their original cerebral hemisphere and cross only within the spinal cord at the level where their associated motor spinal root exit. The fibers that command the inferior motor neurons of the cranial nerves cross to the other side just before the link with the nuclei of these nerves.

 


Related Discussions:- Explain about cerebral hemispheres

Intestinal phases of the ascaris infestation, Q. What are the main symptoms...

Q. What are the main symptoms of the pulmonary and of the intestinal phases of the ascaris infestation? In the pulmonary period the ascaris infestation causes hemoptysis, cough

Which does not support evolution, Which of the following does not support e...

Which of the following does not support evolution? biogeography the fossil record comparative anatomy radiometric dating All of these choices are evidence of/support evolution.

Korarchaeotes, what is the effect that korarchaeotes have on humans?

what is the effect that korarchaeotes have on humans?

Locomotion in annelida, Locomotion in Annelida Before we discuss the ...

Locomotion in Annelida Before we discuss the details of locomotion in annelids, we have to recapitulate the major subdivisions of the phylum Annelida. Phylum Annelida contain

Isolation techniques, Differentiate between spread plating and streaking?

Differentiate between spread plating and streaking?

Discuss in brief distant and contact osteogenesis, Q. Discuss in brief dist...

Q. Discuss in brief distant and contact osteogenesis? Three terms are used to describe individual aspects of bone formation process that occur at implants. They are Osteocondu

Define tertiary level care - public nutrition, Define Tertiary level care -...

Define Tertiary level care - Public Nutrition? This is the highest level of health case available to the community for dealing with their most complex health problems, which ca

Ammonia excretion, There is no store for nitrogen-having compounds as there...

There is no store for nitrogen-having compounds as there is for carbohydrate (glycogen)   or lipids (triacylglycerol).  Thus nitrogen ingested in excess of what is required through

Metabolism of proteins, The major component of food is protein. The protein...

The major component of food is protein. The proteins ingested as part of our diet are not the same proteins required by the body, nor can large molecules be absorbed from the gut.

Explain cis-trans isomers, Explain Cis-trans isomers Atoms or groups a...

Explain Cis-trans isomers Atoms or groups are called  cis or  trans to one another when they project respectively on the same or on opposite sides of a reference plane  identi

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