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

Give the introduction of genesis of coronary artery diseases, Give the intr...

Give the introduction of genesis of coronary artery diseases and risk factors? Cardio-vascular diseases have their roots in the structure and functional alterations in the vasc

What is phylum annelida - segmented worms, What is Phylum Annelida - Segmen...

What is Phylum Annelida - Segmented Worms? Members of this Phylum are commonly known as the segmented worms. The body of a segmented worm is made of many individual ring-like s

Organs involved in the digestion process, The various organs involved  in...

The various organs involved  in  the digestion process are: Alimentary tract which  includes mouth, pharynx, esophagus stomach, small intestine, large intestine, appendix,  rec

Lymph, LYMPH - Lymph is a mobile connective tissue comprising lymph pla...

LYMPH - Lymph is a mobile connective tissue comprising lymph plasma (fluid) and lymphcorpuscles (cells).   COMPOSITIO N - (i )      Lymph Plasma - It is simil

Determine the syndrome of listeriosis, Determine the Syndrome of Listerios...

Determine the Syndrome of Listeriosis Syndrome: Listeriosis in humans is not characterized by a unique set of symptoms since the course of the disease depends upon the state

Explain the functionality of hot air oven, Explain the Functionality of Hot...

Explain the Functionality of Hot Air Oven? Hot air oven sterilizes the object by hot dry air. It kills the microorganisms by oxidizing cellular constituents. Dry Heat is less e

How does water move inside sponges, How does water move inside sponges? Wha...

How does water move inside sponges? What is the function of the pores in these animals? Sponges are filtering beings. They make water enter their bodies by their lateral pores

Why is genetic homozygosity dangerous, Why is genetic homozygosity dangerou...

Why is genetic homozygosity dangerous to a nearly extinct species? Genetic homozygosity leaves no variation for natural selection to act on. Thus, a new disease could wipe

26 The Human Impact on the Environment, What are the principal sources of e...

What are the principal sources of excessive nitrate and phosphate in rivers and lakes?

What are functions of the epithelium, Q. What are some functions of the epi...

Q. What are some functions of the epithelium? The epithelial tissues can perform protection, covering and impermeability against the environment, for instance, in the skin, res

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