Search results
Results from the WOW.Com Content Network
The first list shows number of neurons in their entire nervous system. The second list shows the number of neurons in the structure that has been found to be representative of animal intelligence. [1] The human brain contains 86 billion neurons, with 16 billion neurons in the cerebral cortex. [2] [1]
Most neurons can be anatomically characterized as: [4] Unipolar: single process. Unipolar cells are exclusively sensory neurons. Their dendrites receive sensory information, sometimes directly from the stimulus itself. The cell bodies of unipolar neurons are always found in ganglia.
Glial stem cells are found in all parts of the adult brain. [1] Glial cells greatly outnumber neurons and apart from their supporting role to neurons, glia – astrocytes in particular have been acknowledged as being able to communicate with neurons involving a signalling process similar to neurotransmission called gliotransmission. [4]
Kenyon cells are the intrinsic neurons of the mushroom body, [1] a neuropil found in the brains of most arthropods and some annelids. [2] They were first described by F. C. Kenyon in 1896. [3] The number of Kenyon cells in an organism varies greatly between species.
Nervous tissue, also called neural tissue, is the main tissue component of the nervous system.The nervous system regulates and controls body functions and activity. It consists of two parts: the central nervous system (CNS) comprising the brain and spinal cord, and the peripheral nervous system (PNS) comprising the branching peripheral nerves.
Multipolar neurons constitute the majority of neurons in the central nervous system. They include motor neurons, and also interneurons (relay neurons), which are most commonly found in the cortex of the brain and the spinal cord. Peripherally, multipolar neurons are found in autonomic ganglia. [1]
Most neurons in the central nervous systems of vertebrates, including mammals, are multipolar. [4] In multipolar neurons, multiple processes extend from the cell body including dendrites and axons. Some neurons in the vertebrate brain have a unipolar morphology: a notable example is the unipolar brush cell , found in the cerebellum and granule ...
Many of the cells and vasculature channels within the nervous system make up the neurovascular unit, which regulates cerebral blood flow in order to rapidly satisfy the high energy demands of activated neurons. [2] Nervous systems are found in most multicellular animals, but vary greatly in complexity. [3]