Inter neurons is known to be found between sensory input and motor output/response. Also, the relay neurons are found in the spinal cord and brain where it allows both sensory and motor neurons to communicate.

Motor (Effector)
What the motor neurone does is it conducts impulses from, the CNS to the muscles, glands or the effector organs, it control muscle movements. When the motor neurons are motivated they discharge neurotransmitters that bind to the receptors in the muscles which trigger a response. This is where it leads to a movement. Within the enteric plexus, it controls the gastrointestinal motility, secretion and perhaps absorption.  Performing these functions, the motor neurons is where it acts directly on a huge number of effector cells which includes secretory cells (chief, parietal, mucous, enterocytes, pancreatic exocrine cells), smooth muscle and gastrointestinal endocrine cells. When it comes to the voluntary nervous system the motor neurone is fast conducting which means it is myelinated. When it comes to the automatic nervous system there is no myelin sheath present which means the actions are slow conducting. What they do is they apply smooth muscle in the organs, cardiac muscle in the heart and glands.   

The central nervous system (CNS) ade up by two types of cells, the glial cells and neurones. The gial cells provides framework for the neurones in the CNS. The nerines is the one that is more important of the two, when it comes its function. It transmits information through the CNS by electrical and chemical signals.

Connector Neuron 

Connector neuron is defined as an interneuron which is also known as internuncial neuron, relay neuron, association neuron, connector neuron, intermediate neuron or local circuit neuron. The interneuron is known to be a broad class of neurons which is found in our body. The basic structure of the neuron is where the neurons (nerve cells) has three parts which carries out the functions of communication and integration such as dendrites, axons and axon terminals. It also has a fourth part where the cell body or soma carries out the basic life processes of neurons. This is also where the figure at the right demonstrates a ‘typical’ neuron. 

In the membrane K+ ions are at a HIGH CONCENTRATION. The k+ ions typically should be attracted to the + extracellular environment and diffuse out, but this ks stopped by 

 Transmission of a signal can only happen if there is a resting potential of around 70mV. A neurone membrane isn’t permeable to na+ ions, however…. 

1. The stimulus has to be higher than the minimum value that is called ‘threshold stimulus’ that creates an ‘all or none’ response. The stimulus comes from the external environment such

as changing light/pressure, or from the internal environment like changing blood temperature/pH

2. What causes the membrane to become permeable is the stimulus which lets ions come into the neurone along the gradient which causes DEPOLARISATION

3. The potassium ions exit the neurone to even out the negative charge

4. This is why the ionic movements causes the neurones to become REPOLARISED back to its resting potential.

5. This process can happen again

6. During the opening and closing of the sodium and potassium channels, where there are no exchange of ions, it is called the REFRACTORY PERIOD.

7. As myelinated axons have Nodes of Ranvier, when an action potential (impulse) is transmitted along the axon, the signal goes from node-to-node in order to help the signal travel faster compared to a non-myelinated axon. This is known as SALTATORY CONDUCTION

 What an action potential is able to do is travel along long distances. When depolarisation happens the outside if the membrane becomes depolarised. In addition a stimulus will allow the sodium channels to open because it is above the threshold level and this will cause the sodium ions from the extracellular membrane to go into the membrane. This results in an action potential which stimulates another sodium ion along the axon to open. What this action potential does is it creates a ‘all or none’ response: there will be no action potential that will take place if the stimulus doesn’t produce depolarisation that is higher than the threshold stimulus. Action potential causes the membrane to become polarised. But the potassium ions and the sodium ions are on the incorrect region of the membrane. The stage of the process is called the refractory period what the axon is non-reactive to the stimulus. So, both the ions are then sent back to the resting potential location by the channels. When they go back to their resting potential, the neurone membrane is ready to respond to another stimulus.

REPOLARSATION  

Potassium ions move out if the membrane as sodium ions move in to the membrane and this results in repolarisation where. The membrane is put back to it original polarisation. The potassium ion channels open up that the sodium ion channels close up. Which results in the potassium ions to be out the is the membrane the sodium ions to be inside the membrane 

The synapse 

When the information goes through one neuron, there is a gap in between the two neurons this is called the synapse.  So when the nerve impulse reaches the synapse at the end of a neuron it can’t pass straight to the other neurons. So what it does it triggers the neuron to release chemical neurotransmitter. What this does is it moves across the gap of the two neurons, and when it reaches the other side. It fits into a receptor that its tailor made for it, similar to a key and lock mechanism. What this does is it changes the chemical signal back to the electrical signal.

The spine also known as the backbone or the medulla controls the movement of the body from the bottom of the skull to the pelvis. When you look at the spinal cord it, it is white and firm and it has nerves that extend out of it. These nerves extend to the bones, skin and muscles and aid us to move. The spine has 31 pairs of spinal nerves that split into the following: 12 thoracic, 8 cervical, 5 lumbar, 5 sacral and 1 coccygeal.  The spine is the centre where the body process information that it receives from the brain and t sends this information to the nerves around the body which allows us to move. It also sends signals from the body to the bran which allows us to react correctly. The brain and the body work closely. 

The brain 

The main part of the encephalon is the brain and it has in it the brain stem and the cerebellum. The brain has hemisphere which is it made up by and an area that is called diencephalon, it is also protected by the cranium. The brain makes up two percent of the bodyweight, however it has hundreds of billions that make it. The brain the largest and complex in the body. I will now be discussing in depth two parts of the brain.  

The brain stem  

The brain stem is the part of the brain that is connected to the spine and its role is to control the messages being sent from the rain to the rest of the body. Basic body function such as: swallowing, heart rate, breathing, blood pressure and consciousness is all controlled by the brain stem. What the brain stem consists of is the: pons, midbrain and the medulla oblongata. 

Frontal lobe 

The frontal lobe of the body controls the cognitive skills within the brain. So it’s in charge of problem solving, language, judgement, memory and sexual behaviours. In other words the frontal lobe is the centre of personality and it is what enables us communicate with others.