nervous system

Examples of nervous system in the following topics:

• Introduction to the Nervous System

  • The basic unit of the nervous system is the neuron.
  • The nervous system can be divided into two major parts—the central nervous system (CNS) and the peripheral nervous system (PNS).
  • The central nervous system includes the spinal cord and the brain.
  • The PNS can be further subdivided into the autonomic nervous system and the somatic nervous system.
  • The nervous system of the human body, including the brain and spinal cord (central nervous system) and all the nerves of the body (peripheral nervous system).

• Comparing the Somatic and Autonomic Nervous Systems

  • The peripheral nervous system (PNS, see ) is divided into the somatic nervous system and the autonomic nervous system.
  • The somatic nervous system (SoNS) is the part of the peripheral nervous system associated with the voluntary control of body movements via skeletal muscles.
  • The somatic nervous system consists of three parts:
  • It is classically divided into two subsystems: the parasympathetic nervous system (PSNS) and sympathetic nervous system (SNS).
  • The enteric nervous system is sometimes considered part of the autonomic nervous system, and sometimes considered an independent system.

• Organization of the Nervous System

  • A nervous system is what allows us to react to the changing environment around us.
  • The nervous system is an organ system that coordinates our actions by transmitting signals between different parts of our bodies.
  • The central nervous system (CNS) is composed of the brain, spinal cord, and retina.
  • Along with neurons, the nervous system relies on the function of other specialized cells called glial cells, or glia, that provide structural and metabolic support to the nervous system.
  • Gross organization of the nervous system, with the peripheral nervous system, the spinal, and the cortical levels.

• Functions of the Nervous System

  • The primary function of the nervous system is to coordinate and control the various functions of our body.
  • The nervous system has three overlapping functions.
  • The nervous system is a highly integrated system.
  • Nervous system processes and interprets sensory input and decides what should be done at the each moment.
  • The nervous system activates effector organs such as muscles and glands to cause a response called the motor input.

• Parasympathetic Responses

  • The parasympathetic nervous system regulates organ and gland function during rest and is considered a slowly activated, dampening system.
  • The parasympathetic nervous system (PSNS, or occasionally PNS) is one of the two main divisions of the autonomic nervous system (ANS) (shown in ).
  • The autonomic nervous system (ANS, or visceral nervous system, or involuntary nervous system) is the part of the peripheral nervous system that acts as a control system, functioning largely below the level of consciousness and controlling visceral functions.
  • The sympathetic nervous system can be considered a quick response, mobilizing system; and the parasympathetic a more slowly activated dampening system.
  • The parasympathetic nervous system, shown in blue, is a division of the autonomic nervous system.

• Intro to the Central Nervous System

• Divisions of the Autonomic Nervous System

  • The autonomic nervous system (ANS) contains two subdivisions; the parasympathetic (PSNS) and sympathetic (SNS) nervous systems.
  • The autonomic nervous system (ANS) is classically divided into two subsystems (see : the parasympathetic nervous system (PSNS) and sympathetic nervous system (SNS).
  • The enteric nervous system is sometimes considered part of the autonomic nervous system, and sometimes considered an independent system.
  • In the autonomic nervous system, preganglionic neurons connect the CNS to the ganglion.
  • Distinguish between the parasympathetic and sympathetic subsystems of the autonomic nervous system

• Autonomic Nervous System (ANS)

  • The autonomic nervous system is a part of the peripheral nervous system that controls visceral functions such as heart rate and digestion.
  • The autonomic nervous system (ANS or visceral nervous system or involuntary nervous system) is the part of the peripheral nervous system that acts as a control system functioning largely below the level of consciousness and controls visceral functions .
  • It is classically divided into two subsystems: the parasympathetic nervous system (PSNS) and sympathetic nervous system (SNS).
  • The enteric nervous system is sometimes considered part of the autonomic nervous system, and sometimes considered an independent system.
  • An illustration of neural control of the gut wall by the autonomic nervous system and the enteric nervous system.

• Neurons and Glial Cells

  • In most types of vertebrate animals, it consists of two main parts: the central nervous system (CNS) and the peripheral nervous system (PNS).
  • The PNS includes motor neurons (mediating voluntary movement), the autonomic nervous system (comprising the sympathetic nervous system and the parasympathetic nervous system, which regulate involuntary functions), and the enteric nervous system (a semi-independent part of the nervous system whose function is to control the gastrointestinal system).
  • The nervous system performs several functions simultaneously.
  • Some organisms, such as sea sponges, lack a true nervous system.
  • Octopi may have the most complicated of invertebrate nervous systems.

• Comparing the Nervous and Endocrine Systems

  • The nervous system and endocrine system both use chemical messengers to signal cells, but the speed of transmission is different.
  • The nervous and endocrine systems both work to bring about this adaptation, but their response patterns are different.
  • Both the nervous system and the endocrine system use chemical messengers to signal cells, but the speed at which these messages are transmitted is different.
  • The nervous system responds rapidly to stimuli by sending electrical action potentials along neurons, which in turn transmit these action potentials to their target cells using neurotransmitters, the chemical messenger of the nervous system.
  • The response to stimuli by the nervous system is near instantaneous.