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

Precautions for spore staining in a given bacterial culture, Define some Pr...

Define some Precautions for spore staining in a given bacterial culture? 1. Do not allow malachite green to dry on slide. 2. Decolourization should be done only after coolin

Coronal disassembly, Coronal disassembly - Coronal restoration in the ...

Coronal disassembly - Coronal restoration in the retreatment phase called coronal deassembling or disassemblying. - Coronal deassembling means removal of coronal and radi

What is the choice of a prophylactic agent, Choice of a prophylactic agent ...

Choice of a prophylactic agent An effective prophylactic regimen should be directed against the most likely infecting organisms, but need not eradicate every potential pathogen

Define the advatages of potassium, Define the advatages of Potassium Th...

Define the advatages of Potassium The gross impact of these effects on crop production is manifested  in several ways. Perhaps the first visible indication of a potassium defic

Flower, flowers formation without any leaves?

flowers formation without any leaves?

Explain a reason these cells are used instead of outer body, The cells lini...

The cells lining the inside of the cheek are frequently removed for making observations of basic cell structure. The cells are from stratified squamous epithelium. Explain a reason

What are living and nonliving reservoirs, What are living and nonliving res...

What are living and nonliving reservoirs? Viruses are both living as well as non-living. They have reservoirs of genes. A one nucleotide is a unit of gene. Viral genes make use

Define types of root canal perforations according to size, Define Types of ...

Define Types of Root Canal Perforations According to size According to size: Small perforation: ( smaller than #20 endodontic instrument ) mechanical damage to tissue is

Define biodiversity and ecosystem stability, Define Biodiversity and ecosys...

Define Biodiversity and ecosystem stability? Human's have transformed ecosystems all through the world, frequently replacing diverse natural ecosystems with ecosystems which ar

How fever, How Fever,Illness,Infections,Injury affects the BMR? Any ill...

How Fever,Illness,Infections,Injury affects the BMR? Any illness or fever caused by an illness influences the metabolic rate. Fevers increase the metabolic rate by about 7% for

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