Neurons and Neurotransmitters-The Brains of the Nervous System

The body of a human being is presumed dead when the brain stops functioning. This is because all the functions of the body are controlled by the various segments of the brain. Majorly the nervous system is responsible for the body’s control and communication network. While discharging this function in humans, they do so in three ways and that is to say that they:

• Senses changes both in and outside the body-the sensory function.
• Interprets and explains the changes-the integrative function.
• Responds to the interpretation by making muscles interact and glands secrete hormones or other chemicals into the bloodstream-the motor function.

The nervous system itself has two main parts:

The central nervous system includes the brain and spinal cord which acts as a control center.

The peripheral nervous system includes all other nerve elements. All these elements connect the brain and spinal cord to muscles and glands.

Neurons power their functions

It is important to note that the body of a human being is made up of billions of cells which are ordinarily the basic unit of all living things. This also applies to the single-celled organisms like the bacteria which can perform the basic functions needed to sustain life. These basic functions may include gathering energy from food, reproducing and producing waste materials. Looking at the cells, nearly all of them have three parts which are:

• An outer wall also known as membrane
• A nucleus that contains essential chemicals
• A body of clear fluid called the cytoplasm

Plants, animals and human beings are multicellular meaning creatures with many-cells. Of these cells billions of them are specialize in certain specific functions. For example, some cells would become:

• Part of muscle tissue and help us to move.
• Other cells make up organs, glands, blood, veins, arteries, and bones.

Neurotransmitters cross the gaps between neurons

For it to effectively serve its three functions, the nervous systems which includes the vast circuits of delicate cells which are very much elaborately interconnected and in fact the brain, spinal cord and nerves all over the body are all made up of one kind of cell. These are the nerves cells and they are also known as neurons and as had been indicated that the brain of human beings has billions of neurons.  Now the question you need to ask yourselves is does your spinal cord and all the nerves that fan out from the spinal cord to your glands, organs, and muscles.

The specific functions of the neurons are to allow your brain to learn reason and be able to remember things. Through these activities the body responds and adjusts to changes in the environment. These changes are also called stimuli, they will set off impulses in our sense organs like: the eye, the ear and other organs of taste and smell and sensory receptors located in the skin joins, muscles and other parts of the body. Now having listened to all these it is important to note that every time you feel something including the effects of a drug, know that millions of neurons are firing messages to form one another.

Each neuron may have thousands of branches that connect it to other neurons and these branches are called dendrites or axons. Dendrites carry messages towards the cell body while axons carry messages away from the cell body to another neuron. Axons can extend as long as four feet in humans and in some animals even longer.

In the beginning it was believed that axons and dendrites simply run through the body continuously like a wire but letter on a space was discovered between each axon and dendrite. This space in known as a synaptic gap or synapse and it is the space between the axon of one neuron and the dendrite of the next neuron in a nerve pathway. This gap is negligibly small and it is about one millionth of an inch, it is that small.

Research finding originally believed that electrical impulses jumped these gaps like electricity does across the gap in spark plug but this theory has been ruled out as it is now known that this was never true. It is the chemicals which travel across the gap and not electrical impulses and these chemicals are also neurotransmitters.

A number of chemical building blocks for neurotransmitters such as amino acids come from the kinds of food we eat meaning that our bodies have the ability to manufacture or produce neurotransmitters. Neurons offer a storage package for neurotransmitters known as vesicles which are located very close to the endings of each axon. They (neurons) synthesize some neurotransmitters right in the vesicle while other neurotransmitters are synthesized in the body of the cell and transported to the vesicle. Most of the addictive substances have the ability to change the effects of neurotransmitters on neurons. We will be able to better comprehend how these substances work when we get to know about neurotransmitters and how they act as chemical messengers

Neurotransmitters meet three criteria

Neurotransmitters are molecules-groups of atoms joined by a chemical bond which act as a unit. For them to be called neurotransmitters a molecule must meet the following three criteria:

• The molecule must be present and evenly distributed in the brain meaning that the molecules must not just concentrate in one segment but must spread out among different types of neurons and across all segments of the brain that have different functions.
• Chemical criteria that is to say the enzymes which help in creating the neurotransmitter must be available in the brain. An enzyme is a catalyst protein which speeds up chemical reactions within the body. It is also important that these enzymes be available in areas where the neurotransmitters are found.
• The criterion of mimicry assuming that we inject directly a neurotransmitter into a section of the brain known to contain certain neurons, this injection should be able to imitate the effects of electrically stimulating the same neurons.

Neurons and Neurotransmitters-The Brains of the Nervous System