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Immediately behind the brain is the subesophageal ganglion, which is composed of three pairs of fused ganglia.
It controls the mouthparts, the salivary glands and certain muscles.
The head segment contains the brain, also known as the supraesophageal ganglion.
In the insect nervous system, the brain is anatomically divided into the protocerebrum, deutocerebrum, and tritocerebrum.
Special effects, water projection, fiber optics and lasers make this one of Disneyland’s must see events.
The nervous system is the part of an animal's body that coordinates its actions and transmits signals to and from different parts of its body.
Nerves that transmit signals from the brain are called motor or efferent nerves, while those nerves that transmit information from the body to the CNS are called sensory or afferent.
Most nerves serve both functions and are called mixed nerves.
Among the most important functions of glial cells are to support neurons and hold them in place; to supply nutrients to neurons; to insulate neurons electrically; to destroy pathogens and remove dead neurons; and to provide guidance cues directing the axons of neurons to their targets.
A very important type of glial cell (oligodendrocytes in the central nervous system, and Schwann cells in the peripheral nervous system) generates layers of a fatty substance called myelin that wraps around axons and provides electrical insulation which allows them to transmit action potentials much more rapidly and efficiently.
Recent findings indicate that glial cells, such as microglia and astrocytes, serve as important resident immune cells within the central nervous system.
Nervous tissue first arose in wormlike organisms about 550 to 600 million years ago.
In vertebrate species it consists of two main parts, the central nervous system (CNS) and the peripheral nervous system (PNS). The PNS consists mainly of nerves, which are enclosed bundles of the long fibers or axons, that connect the CNS to every other part of the body.