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

Surface Processes on Earth, Which of the following is not a type of mass mo...

Which of the following is not a type of mass movement that results from the force of gravity? A. Landslide B. Creep C. Deflation D. Mudflow

Protein x has an absorptivity of 0.4 ml, Protein X has an absorptivity of 0...

Protein X has an absorptivity of 0.4 mL . mg -1 . cm-1 at 280nm. What is the ab sorbance at 280 nm of a 2.0 mg. mL-1 solutionof protein X ? (Assume the light path is 1 cm).

Pathophysiology of leukemia, Pathophysiology   Leukocytes develop fiom ...

Pathophysiology   Leukocytes develop fiom stem cells located in the bone marrow. During  leukocyte maturation, cells become committed  to specific cell types and develop  throu

Storage excretion, Storage Excretion Many insects exhibit a phenomenon...

Storage Excretion Many insects exhibit a phenomenon known as storage excretion. If excretory products are stored in the body instead of being eliminated, no water is expended

Free-radical addition reaction, Why is the reaction of ethane and chlorine ...

Why is the reaction of ethane and chlorine not a free-radical addition reaction? Because no free radicals are include in the reaction process only carbo cations and Cl- are evo

What are the main human diseases caused by fungi, What are the main human d...

What are the main human diseases caused by fungi? The main human diseases caused by fungi are coccidioidomycosis, histoplasmosis, blastomycosis, paracoccidioidomycosis, or Sout

Impulse transmission, The conduction of impulse in a nerve fibre is. a elec...

The conduction of impulse in a nerve fibre is. a electrochemical process. Maximum speed of transmission of nerve impulse can be 13 metre/second due to axoplasm is much resistant to

Define metabolic activity and cell constituents, Define Metabolic Activity ...

Define Metabolic Activity and Cell Constituents? Metabolic activity like amount of acid produced or CO 2 produced is directly proportional to the number of bacteria present, s

Explain the sticky films - food microbiology, Explain the Sticky Films - Fo...

Explain the Sticky Films - Food Microbiology? Sticky films or tape are pressed against the surface to be assessed. Exposed film/tape is then pressed on the agar plate and analy

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