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

Elaborate about sarcodina: amoebas, Sarcodine protozoans are amoebas, and t...

Sarcodine protozoans are amoebas, and there are two types of them: shelled and naked. As you examine the prepared slides you should be able to see water expulsion vesicle, nucleus,

Define measuring body composition- skin fold measurement, Define measuring ...

Define measuring body composition- Skin fold measurement? The clinical use, skin fold measurement can be taken with the help of calipers. The calipers are applied at constant p

What event marks the beginning of the menstrual cycle, Q. What event marks ...

Q. What event marks the beginning of the menstrual cycle? What is the blood concentration of FSH, LH, estrogen and progesterone in this phase of the cycle? By convention the me

Which of the processes results in the atp, Which of the processes results i...

Which of the processes results in the most ATP production within a cell?

Transport in phloem, Transport in Phloem The basic necessities of plan...

Transport in Phloem The basic necessities of plants, water, are taken up by the roots. Another purpose served by the roots is to absorb water soluble mineral nutrients from th

How does the poison cyanide act upon the aerobic respiration, Q. How does t...

Q. How does the poison cyanide act upon the aerobic respiration? Cyanide is a poison that restrains the last cytochrome of the respiratory chain, interrupting the ATP formation

Explain about the complete proteins, Explain about the Complete proteins? ...

Explain about the Complete proteins? We now know that proteins are composed of amino acids and that proteins differ in their amino acid make-up. Proteins lacking in one or more

Relationship between mind and brain, Q. Relationship between Mind and Brain...

Q. Relationship between Mind and Brain? In modern times, before the 20th century, the most popular interpretation of the mind-brain relationship was some version of dualism. It

What is implant prior to stage 2 surgery, Enumerate the different means of ...

Enumerate the different means of evaluating the implant prior to stage 2 surgery. The Different means for evaluating the implant prior to stage 2; i) Radiographic evaluation

Learning objectives of coronary artery disease, Q. Learning objectives of c...

Q. Learning objectives of coronary artery disease? • describe the various forms of coronary heart diseases, • enumerate the risk Factors (genetic and environmental) in causati

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