Nerve Cell PDF

Neurons differ in the direction of the message and type of impulse they carry: (a) sensory neurons (afferent) carry impulses from the enviro...

Neurons differ in the direction of the message and type of impulse they carry: (a) sensory neurons (afferent) carry impulses from the environment to the brain or spinal cord; (b) motor neurons (efferent) carry impulses from the brain or spinal cord to the muscles; & (c) associative neurons (interneuron) integrate data from sensory neurons then relay commands to motor neurons. BASIC FUNCTIONS OF THE NERVOUS SYSTEM The nervous system is involved in receiving information about the environment around us (sensation) and generating responses to that information (motor responses). The process of integration combines sensory perceptions and higher cognitive functions such as memories, learning, and emotion to produce a response. SENSORY PROCESSING Sensory processing is typically divided into eight main types. They can include:  neuron, basic unit structure and ❑ Proprioception. Proprioception is the “internal” sense of awareness function in the nervous; you have for your body. It’s what helps you maintain posture and collectively sense environmental motor control, for example. It also tells you about how you’re change, integrate sensory inputs moving and occupying space. then activate muscles or glands ❑ Vestibular. This term refers to the inner ear spatial recognition. It’s that initiate or carry out what keeps you balanced and coordinated. responses ❑ Interoception. This is the sense of what’s happening in your body. It may be best understood as how you “feel.” This includes whether  The neuron consists of a (a) you feel hot or cold and whether you feel your emotions. dendrites which impulses ❑ Five senses. Lastly, there are the 5 common senses — touch, away from the cell, (b) axons hearing, taste, smell, and sight. or nerve fibers which carry impulses away from the cell ❑ Neurons have the special ability to carry body towards the dendrites of signals or impulses. A nerve impulse is an other neurons or cell body of electrochemical signal moving along a muscle cells and (c) cell body neuron. It is a combination of an electrical which contains the nucleus charge and chemical reaction. and cytoplasm. ❑ A nerve impulse can’t jump from one neuron to another. When a nerve impulse comes to an end of an axon, it produces a chemical neurotransmitter. The chemical crosses the space between neuron called synapse and stimulates the nerve impulse to start in the next dendrite. ❑ A stimulus is any factor in the environment that influences behavior. A response is a reaction to a condition or stimulus. An organism must be able to respond to a stimulus in order to survive. Reaction time is the length of time between application of a stimulus and detection of a response. ❑ When a receptor such as an organ perceives a stimulus, the impulse is sent to the brain by the sensory neurons, which then transmit information from one nerve cell to another. As the message reaches the brain, it processes the information and commands an effector such as a muscle or an organ to respond. The message coming from the brain is sent through the motor neurons. ❑ The Nervous system is very important in helping to maintain the homeostasis (balance) of the human body. It is a series of sensory receptors work with the nervous system to provide information about changes in both internal and external environments. ❑ The nervous system maintains homeostasis by controlling and regulating the other parts of the body. A deviation from a normal set point acts as a stimulus to a receptor, which sends nerve impulses to a regulating center in the brain.