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ENDOCRINE SYSTEM AND BEHAVIOR

  ENDOCRINE SYSTEM AND BEHAVIOR Types   of chemical messenger systems :   1. Neurotransmitters - are released by axon terminals of   neurons into the synaptic junctions and act locall y to control nerve cell functions. 2. Endocrine hormones - are released by glands or specialized   cells into the   circulating blood and influence   the function of target cells at another location   in the body. 3. Neuroendocrine hormones -   are secreted by neurons   into the circulating blood and influence the function   of target cells at another location in the body 4.  Paracrines- Cells produce paracrines into the extracellular fluid, which have an effect on surrounding target cells of a different type. 5.  Autocrines- Autocrines are secreted into the extracellular space by cells. fluid and have an impact on the function of the same cells that they were created 6.  Cytokines are peptides secreted by cells into th e extracellular f...

Plasticity of brain

                                                Neuroplasticity Causes of Brain Damage six causes of brain damage: brain tumors, cerebrovascular disorders, closed head injuries, infections of the brain, neurotoxins, and genetic factors. Brain Tumors A tumor, or neoplasm (literally, “new growth”), is a mass of cells that grows independently of the rest of the body. About 20 percent of tumors found in the human brain are meningiomas tumors that grow between the meninges, the three membranes that cover the central nervous system. All meningiomas are encapsulated tumors—tumors that grow within their own membrane. As a result, they are particularly easy to identify on a CT scan, they can influence the function of the brain only by the pressure they exert on surrounding tissue, and they are almost always benign tumors—tumors that are surgically removable w...

Structure and function of neurons

Structure and function of cells of nervous system Brain - It is the organ that moves the muscles. It is very flexible in that it makes us behave in different ways according to the environment , let us learn from our experiences and all these abilities are possible by billions of cells found in nervous system called neurons. Types of neurons : Sensory neurons - A neuron that detect changes in the external or internal environment , gathers these information and sends them to the CNS Motor neurons - located within the central nervous system and control  contraction of muscles and secretion of the glands , control movements of  body Interneuron - located entirely within the CNS . This is of two types: 1.Local interneurons - Form circuits with nearby neurons and analyse small pieces of information 2.Relay interneurons - Connect circuits of local interneurons from one region of the brain to another Cells of nervous system: Most important cells of nervous sys...