Most neurons in the body can regenerate axons and dendrites, since they are outcroppings of the neural soma (the cell body). It does this through NGF (nerve growth factor), BDNF (brain-derived neurotrophic factor), and other regulatory mechanisms. In addition, receptors and other neuron "parts" can be regenerated or degraded as needed, based on these regulatory factors.
While it was previously believed that central nervous system neurons cannot regrow, this has been proven to be only half right.
While fully differentiated neurons (already formed brain cells, etc.) cannot regenerate themselves, neuroscientists have found proof of stem cells within the hippocampus that remain well into adulthood. These stem cells can be triggered to divide and regrow NEW brain tissue. However, one can imagine that such regenerative activity is sparse and has to be very carefully regulated...otherwise, overgrowths would result in tumors or disruption of the very connections that make the brain work effectively.
no, that is why when you become paralyzed you are paralyzed for life.
False
Yes.
yes cranial nerves can regenerate
It is called a dendrite.~
The nerve cells are ensheathed in the cns by myelin which is a dielectric material. The myelin layer extends only upto the axon of a neuron. It is essential for the proper functioning of the nervous system.
The neuroglia ("nerve glue"), or glial cells, which in the CNS include Astrocytes, Ependymal cells, Microglia, and Oligodendrocytes.
neurons is the incorrect answer. The correct answer is ganglia.
Yes
False
True
Nerves that conduct to the CNS are afferent.
Eletrical impulses throughout the nervous system
Yes, in the CNS it is oligodendrocytes that myelinate axons.
yes cranial nerves can regenerate
A neuron is an individual cell in the PNS or CNS that can be excited and conduct impulses along its axon. A nerve is a bundle of multiple neuron fibers that each are carrying their own signals. They are protected by connective tissue. Eventually the neuron fibers diverge away from the nerve to reach their destination.
All preganglionic sympathetic fibers leave the CNS at the thoracolumbar region, yes.
The usual name for a bundle of nerve processes within the CNS is "tract" or "fasciculus"
the spinal nerve sends nerve impulses away from the CNS
Bundles of neuron processes are called tracts in the cns and nerves in the pns