A nerve net is a type of simple nervous system that is found in members of the phylumcnidaria. Nerve nets consist of interconnected neurons lacking a brain. This nervous system allows cnidaria to sense touch and pain, and to detect food and other chemicals, but in a rudimentary way. Although the nerve net keeps the animal aware of its environment, it has trouble alerting the animal from where the stimulus is coming. For this reason, simple animals with nerve nets, such as hydra, will typically respond in the same way to contact with an object, regardless of where the contact occurs. The nervous system of an animal coordinates the activity of the muscles, monitors the organs, constructs and also stops input from the senses, and initiates actions. ... Phylum (plural: phyla) is a taxon used in the classification of animals, adopted from the Greek phylai the clan-based voting groups in Greek city-states. ... Classes Anthozoa- Corals and sea anemones Cubozoa- Sea wasps or box jellyfish Hydrozoa- Hydroids, hydra-like animals Scyphozoa- Jellyfish Cnidaria (silent c - pronounced /naɪˡdeɹiə/ from New Latin cnida, fr. ... Drawing by Santiago Ramón y Cajal of cells in the pigeon cerebellum. ... Comparative brain sizes In animals, the brain, or encephalon (Greek for in the head), is the control center of the central nervous system. ... The term stimulus (plural: stimuli) has several related meanings: In physiology, a stimulus is something external that elicits or influences a physiological or psychological activity or response. ... Species Hydra americana Hydra attenuata Hydra canadensis Hydra carnea Hydra cauliculata Hydra circumcincta Hydra hymanae Hydra littoralis Hydra magnipapillata Hydra minima Hydra oligactis Hydra oregona Hydra pseudoligactis Hydra rutgerensis Hydra utahensis Hydra viridis Hydra is a genus of simple, fresh-water animals possessing radial symmetry. ...
Although the nervenet keeps the animal aware of its environment, it has trouble alerting the animal from where the stimulus is coming.
For this reason, simple animals with nervenets, such as hydra, will typically respond in the same way to contact with an object, regardless of where the contact occurs.
The facial nerve is a specific motor nerve (a nerve which tells certain muscles to contract) which controls the muscles on the same side of the face.
The facial nerve is the seventh of the twelve cranial nerves which have been named as such because they all exit the brainstem through the base of the skull.
A disorder of the facial nerve may result in facial muscle paralysis, weakness, or twitching of the face; dryness of the eye or the mouth; or alteration of taste on the affected side.
Feeds |
Contact