Central Nervous System

Resting potentials require ions as they play a vital role in the process. In the surface membrane of a cell there are protein carriers. These actively pump Na+ ions out of the cytoplasm to the outside of the cell. At the

A lesser amount of Potassium ions diffuse out across the membrane, leaving behind a less negative charge. The

The nervous system is a multiplexed body system that controls most other body systems directly or indirectly by sending and receiving signals through a complex system of nerves. As a whole, the nervous system can be broken down into the central nervous system (CNS) and peripheral nervous system (PNS). The CNS is composed of the brain and spinal cord while the PNS is composed of peripheral nerves that branch off of the spinal cord and continue to branch to reach the most distal points of the limbs. The PNS can be further broken down into the afferent and efferent division. The afferent division deals with information brought to the CNS from the nerve receptors. Furthermore, the afferent division breaks down into somatic sensory receptors whose

and the spinal rope and go to specific regions of the body. The peripheral nervous

When a membrane is excited depolarization begins. When the membrane depolarizes the resting membrane potential of -70 mV becomes less negative. When the membrane potential reaches 0 mV, indicating there is no charge difference across the membrane. the sodium ion channels start to close and potassium ion channels open. By the time the sodium ion channels finally close. The membrane potential has reached +35 mV. The opening of the potassium channels allows K+ to flow out of the cell down its electrochemical gradient ( ion of like charge are repelled from each other). The flow of K+ out of the cell causes the membrane potential to move in a negative direction. This is referred to as repolarization. ( Marieb & Mitchell, 2009). As the transmembrane potential comes back down towards its resting potential level and the potassium channels begins to close, the trasmembrane potential level goes just below -90mV, causing a brief period of hyperpolarization (Martini, Nath & Bartholomew, 2012). Finally, as the potassium channels close, the membrane turns back to its resting potential until it is excited or inhibited again.

The anatomical and functional divisions of the nervous system are divided into two categories the central nervous system (CNS) and the peripheral nervous system (PNS).

When the cell reaches the resting potential, then the cell can undergo depolarization. During the process, the charge within the cell goes from negative to positive. For this to happen, many events occur along the plasma membrane. The sodium potassium pump continues to work but the voltage gated ion channels that were closed during resting potential become open due to an electrical stimulus. Sodium enters into the cell again and positive sodium ions change the charge inside the cell from negative to positive. When the inside of the cell is positively charged, depolarization is

The extracellular Na+ did not alter the membrane potential in the resting neuron because the Na+ channels were mostly closed.

The neuron’s resting membrane potential is usually -70 millivolts. This charge comes from the fact that there are more negatively charged sodium ions outside the cell than there are positive potassium ions inside the cell. These ions are arranged by the sodium-potassium pump: for every 2 potassium ions it pumps into the cell, it pumps out 3 sodium ions. The membrane is also riddled with ion channels, large proteins that provide passage when their respective gates open. Most are voltage-gated channels, which open or close at certain membrane potentials. Ligand gated channels that only open when a specific neurotransmitter or hormone attaches to it. Finally, mechanically gated channels open in response to physically stretching the membrane. When the gates open, ions diffuse across that membrane down the electro-potential gradient.

The nervous system is a network of nerves and neurons that transmit signals from the brain to different parts of the body. This system is broken into two main divisions the central nervous system and the peripheral nervous system (Victoria, 2013).

The peripheral nervous system (PNS) is connected directly to the central nervous system, and consists of neurons and nerves that send information back and forth the CNS. Furthermore, the peripheral nervous system can be divided into two sections, the sensory nervous system and the motor nervous system. The Sensory The sensory nervous system is in charge of transmitting data from a variety of internal organs or from external stimuli to the central nervous system using sensory nervous cells. On the other hand, the cells of the motor nervous system (motor neurons), take the impulse from the CNS to effectors, which include glands and muscles. In addition, the motor nervous system can be further divided into the somatic nervous system, controls voluntary actions of the skeletal muscle and external sensory organs, whilst the autonomic nervous system operates

The nervous system is divided into two major sections: There is the central nervous system and the peripheral nervous system.

Whenever the balance is altered, the process of transmitting electrical signals, which is called action potential initiates by carrying information across a neuron’s axon; which is called resting membrane potential. This process occurs as uneven ions distribution flow across cell membrane, creating electrical potential. As a result, the duration of active potential can be as fast as 1 ms. Similarly, the average resting membrane is between -40 mV and -80 mV. Since the membrane from inside is more negatively charged than the outside, it reflected on the negative average voltage readings of the resting membrane.

The human nervous system is divided into two parts, the central nervous system and the peripheral nervous system. The central nervous system, CNS, is just the brain and spinal cord. The peripheral nervous system, PNS, includes the nerves and neurons that extend outwards from CNS, to transmit information to your limbs and organs for example. Communication between your cells is extremely important, neurons are the messengers that relay information to and from your brain.

The nervous system is split up into two parts; the peripheral (PNS) and central (CNS) nervous systems. The central nervous system consists of two main parts; the brain and spinal cord. The brain receives and processes information as well as deal with memories, thoughts, emotion, and much more. The spinal cord mainly deals with sending out signals from the brain to the rest of the body, as well as control