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

What is tricuspid valve annuloplasty, Q. What is Tricuspid valve annuloplas...

Q. What is Tricuspid valve annuloplasty? It depends upon the cause of tricuspid regurgitation. Specific therapy is directed towards the particular cause of pulmonary artery hyp

What is cross contamination, Q. What is cross contamination? Cross cont...

Q. What is cross contamination? Cross contamination is the passage of micro-organisms from one person to another via any route direct or indirect.

What percentage of the offspring would be tall, Tall (T) plants are dominan...

Tall (T) plants are dominant and short (t) plants are recessive. Two heterozygous tall plants are crossed. What percentage of the offspring will be tall?

Why immune response involves the activities of proteins, The immune respons...

The immune response involves the activities of proteins, cells, and the lymphatic system.

Differences among nematodes and annelids, What are the morphological simila...

What are the morphological similarities and differences among nematodes and annelids? Nematodes, like annelids, have a cylindrical elongated body. Annelids differentiate from

Define most probable number (mpn) method, Define Most Probable Number (MPN)...

Define Most Probable Number (MPN) Method? The MPN method is like agar shake tube method where no agar is used. The dilutions of the microbial suspension are made in liquid medi

How nutritional status influences the age, How nutritional status influence...

How nutritional status influences the age? The nutritional status influences the age-related rate of functional decline in many organ systems in the body. Nutrition is also an

Explain the principles of isolated soybean proteins, Principles of Isolated...

Principles of Isolated soybean proteins The basic principles of ISP production are simple. Soybean protein isolates are obtained by selective solubilisation of  the protein (e.

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