Both of these systems can stimulate and inhibit effectors. The ANS is further divided into the sympathetic nervous system and the parasympathetic nervous system. One of its main roles is to regulate glands and organs without any effort from conscious minds. The (ANS) is part of the peripheral nervous system. It is made up of two main parts: the autonomic and the somatic nervous systems. The portion of the nervous system lying outside the brain and spinal cord. Nerves branch off from the spinal cord into the arms, legs, and torso. It is protected by the bones of the spine (vertebrae). The spinal cord connects to the brain and runs the length of the body. The brain organizes and supervises the workings of the body, while its higher functions give us consciousness and personality. This soft, jelly-like organ has countless billions of neural cross-connections. The brain is a powerhouse of the body, even though it only makes up two percent of the body’s weight. They are wrapped in a thin lining called meninges and bathed with cerebrospinal fluid (CSF). The brain and spinal cord make up the (CNS). Unlike other cells in the body, neurons are not easily replaced if they die or are damaged by infection or injury. Messages jump the synapse from one neuron to the next, using special chemicals called neurotransmitters. The space between the bump and the dendrite is called a synapse. Each bump sits near to a dendrite from another neuron. The axon feathers out and has several bumps on it. In many cases, the axon is coated by a specialized membrane called the myelin sheath. All neurons have finger-like projections called dendrites and a long fiber called an axon. Neurons are shaped differently depending on where they are in the body and what role they play. ![]() The basic building block of the nervous system is a nerve cell or neuron. The nervous system uses both electrical and chemical means to send and receive messages.įig: Classification of the nervous system Neurons: Motor nerves (efferent) in the PNS carry signals from the control center to the muscles, glands, and organs to regulate their functions. ![]() The sensory nerves (afferent) and sense organs of the peripheral nervous system (PNS) monitor conditions inside and outside of the body and send this information to the CNS. The brain and spinal cord form the control center known as the central nervous system (CNS), where information is evaluated and decisions made. Together, these organs are responsible for the control of the body and communication among its parts. The nervous system consists of the brain, spinal cord, sensory organs, and all of the nerves that connect these organs with the rest of the body.
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