The brain contains at least ten times more glia than neurons. Glia perform many jobs. Researchers have known for a while that glia transport nutrients to neurons, clean up brain debris, digest parts of dead neurons, and help hold neurons in place.
Current research is uncovering important new roles for glia in brain function. Explain the brain to your students with a variety of teaching tools and resources. Engage local scientists to educate your community about the brain. For Educators Log in. Also In Anatomy. Sex Differences in the Brain.
The Mysterious, Multifaceted Cerebellum. Einstein's Brain. Spinal Cord. All neurons have the same basic structure: Dendrites extend from the cell body dendron - greek for tree. These are fairly short, with lots of branches, and they are the points at which nerve impulses are received by the cell.
The cell body perikaryon. Most of the cell bodies of neurons are in the central nervous system brain and spinal cord , or in the ganglia which lie just outside the spinal cord of the peripheral nervous system.
The axon : a single nerve 'fibre' which transmits impulses to the distal end. Axons can be very long - around 1 metre, and vary in diameter from 0. There are three basic shapes to the neurons : bipolar single axon and single dendrite - special neurons in the sensory pathways for sight, smell and balance.
One axon extends centrally toward the spinal cord, the other axon extends toward the skin or muscle. Multipolar neurons have many processes that extend from the cell body. However, each neuron has only one axon examples: spinal motor neurons, pyramidal neurons, Purkinje cells.
Check out the Gallery of Neurons to see some pictures of real neurons or "Sidewalk Cells" to see photographs of neurons on the street. What is inside of a neuron? A neuron has many of the same organelles such as mitochondria, cytoplasm and a nucleus, as other cells in the body. Did you know? Neurons are the oldest and longest cells in the body! You have many of the same neurons for your whole life.
Although other cells die and are replaced, many neurons are never replaced when they die. In fact, you have fewer neurons when you are old compared to when you are young. On the other hand, data published in November show that in one area of the brain the hippocampus , new neurons CAN grow in adult humans.
Neurons can be quite large - in some neurons, such as corticospinal neurons from motor cortex to spinal cord or primary afferent neurons neurons that extend from the skin into the spinal cord and up to the brain stem , can be several feet long! Types of Neurons Nerve Cells The human body is made up of trillions of cells. Neurons are similar to other cells in the body because: Neurons are surrounded by a cell membrane.
Neurons have a nucleus that contains genes. Neurons contain cytoplasm, mitochondria and other organelles. Neurons carry out basic cellular processes such as protein synthesis and energy production. However, neurons differ from other cells in the body because: Neurons have specialize cell parts called dendrites and axons. Dendrites bring electrical signals to the cell body and axons take information away from the cell body.
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