Portal:Human body/Nervous System

From Wikipedia, the free encyclopedia
Jump to: navigation, search

Nuvola apps kalzium.svg Science: Astrolabe-Persian-18C.jpg History of science   P philosophy.png  Philosophy of science   Complex adaptive system.svg Systems science   Nuvola apps edu mathematics-p.svg Mathematics   EscherichiaColi NIAID.jpg Biology   Nuvola apps edu science.svg Chemistry   Stylised atom with three Bohr model orbits and stylised nucleus.svg Physics   Gnome-globe.svg Earth sciences   Nuvola apps display.png Technology  

Main Page   Cardiovascular
  Digestive System   Integumentary
  Things you
can do
The Human Body-Nervous System Portal

The nervous system is an organ system containing a network of specialized cells called neurons that coordinate the actions of an animal and transmit signals between different parts of its body. In most animals the nervous system consists of two parts, central and peripheral. The central nervous system of vertebrates (such as humans) contains the brain, spinal cord, and retina. The peripheral nervous system consists of sensory neurons, clusters of neurons called ganglia, and nerves connecting them to each other and to the central nervous system. These regions are all interconnected by means of complex neural pathways.

edit  watch  

Selected Article

Human brain and skull
The human brain is the center of the human nervous system. Enclosed in the cranium, it has the same general structure as the brains of other mammals, but is over three times as large as the brain of a typical mammal with an equivalent body size. Most of the expansion comes from the cerebral cortex, a convoluted layer of neural tissue that covers the surface of the forebrain. Especially expanded are the frontal lobes, which are associated with executive functions such as self-control, planning, reasoning, and abstract thought.

The portion of the brain devoted to vision is also greatly enlarged in human beings.

edit  watch  

Selected Picture

Major elements in synaptic transmission
Credit: http://www.nia.nih.gov/Alzheimers/Publications/UnravelingtheMystery/

An electrochemical wave called an action potential travels along the axon of a neuron. When the wave reaches a synapse, it provokes release of a puff of neurotransmitter molecules, which bind to chemical receptor molecules located in the membrane of the target cell.

edit  watch  

Nervous System ImageMap

Click the Various parts of the Image to get Information about it.

Frontal Lobe Somatomotor system Parietal lobe Occipital lobe Cerebellum Temporal lobe Medulla oblongataCerebrum lobes.svg
edit  watch  

Did you know...

  • ...There are 45 miles of nerves in the skin of a human being?
  • ...Though it makes up only 2 percent of our total body weight, the brain demands 20 percent of the body's oxygen and calories
  • ...that the human brain alone consists of about a 100 billion neurons. If all these neurons were to be lined up, it would form a 600 mile long line.
  • ...that In humans, the right side of the brain controls the left side of the body, while the left side of the brain controls the right side.

Purge server cache