Hormones vs Neurotransmitters: Difference and Comparison

Biology encompasses various animals, plants, and other living organisms. What each of these organisms is made of is essentially a bunch of chemicals.

There are different sets of chemicals for each specific purpose.

When the chemicals are used to transmit some message or get a response from a specific part of the body of an organism, this is where hormones and neurotransmitters come into play. On the face of it, their purpose might seem similar. However, they have vastly different functionalities.

Key Takeaways

1. Hormones are chemical messengers secreted by glands in the endocrine system, travelling through the bloodstream to affect target organs and tissues; neurotransmitters are chemical messengers released by neurons in the nervous system, transmitting signals between nerve cells and muscles or glands.
2. Hormones tend to have a slower, more long-lasting effect on the body than neurotransmitters; neurotransmitters have a faster, more immediate effect.
3. Hormones regulate various bodily functions, such as metabolism, growth, and reproduction, while neurotransmitters are responsible for cognitive functions, emotions, and movements.

Hormones vs. Neurotransmitters

Hormones are chemicals released into the bloodstream directly to bring different changes in the body. Hormones can be present in both plants and animals. Neurotransmitters are messenger chemicals the nervous system uses to transmit messages from one place to another.

Hormones are chemical messengers that are directly put into the bloodstream. Hormones are responsible for most of the bodily changes that occur in the body.

Some examples of such bodily changes are growth and development, metabolism, sexual function, cognitive abilities, etc. However, other than these, hormones are responsible for things such as adrenaline which prompts the fight or flight response.

Hormones are found in both plants and animals.

Neurotransmitters, conversely, are chemical messengers used by the nervous system to transmit messages from one place to another. The target location can be nerves, muscles, or glands.

It is important to note that neurotransmitters are only found in animals.

Comparison Table

Parameters of Comparison	Hormones	Neurotransmitters
Availability	Found in both plants and animals.	Found only in animals.
System used	Uses the endocrine system.	Uses the nervous system.
Mode of transportation	It is very fast and works in milliseconds.	Goes via the synaptic gap.
Function	Controls growth, development, reproduction, etc.	Transmits messages between nerve cells.
Functionality speed	Can take hours or even days. Slow.	It is very fast and works in milliseconds.

What are Hormones?

Hormones are chemical messengers the endocrine system uses to regulate specific organs or tissues. The endocrine system does this by releasing hormones into the bloodstream.

Usually, the organ or tissue to be regulated is not very far from the gland which releases the hormone. When the hormone reaches the target location via the bloodstream, special receptors can recognize only that chemical and nothing else.

On reaching the target, the receptors receive the hormone, and a chemical reaction occurs, thus causing the desired result required by the body.

There are numerous hormones, and each of them has different purposes. Hormones are secreted by organs called ‘glands.’

The major glands which regulate our day-to-day functions are:

• Pituitary gland
• Hypothalamus
• Pineal gland
• Adrenals
• Testes
• Ovaries
• Parathyroids

The pituitary gland is the most important in our body. It is also known as the ‘master gland.’

It is important in regulating body functions and well-being. It controls the functioning of all other glands, hence the name ‘master gland.’ 

The most common examples of hormones present in the body are estrogen, progesterone, testosterone, adrenaline, serotonin, cortisol, etc. 

When a hormone is secreted in great amounts or when it is secreted in a lesser amount than required, it causes a chemical imbalance in the body. The most common example of this is insulin.

Insulin helps maintain the sugar level in our blood and is released by the pancreas. When insulin is released in large amounts, it absorbs too much sugar and causes the liver to release less glucose.

This leads to a condition called hypoglycemia. Again, when insulin is released in insufficient amounts, there is an excess of sugar in our blood, and thus causes a condition called diabetes. 

Genes largely determine hormonal secretion. However, it can be maintained well to a large extent by maintaining a proper diet and regular exercise.

What are Neurotransmitters?

Neurotransmitters are the chemical messengers used by the nervous system to transmit messages from one nerve cell to another. We must understand how these chemicals work and how the nerve cells are arranged.

There are two ends of a nerve cell. One end is called ‘Axon,’ and the other is called ‘Dendrite.’

The cells are arranged so that the axon faces the dendrite. Now, there is a small gap between these two cells, where neurotransmitters are used. 

Neurotransmitters are chemicals that are Axon terminal of one cell and received by the dendrite terminal of another cell. These neurotransmitters are the mode of transmission of information between the gaps of the nerve cells.

Neurotransmitters are classified into three major categories, amino acids, peptides, and monoamines. Other neurotransmitters are gasotransmitters, trace amines, purines, catecholamines, etc.

There are quite a few diseases associated with neurotransmitters. The most common disease is Parkinson’s disease.

This disease is a progressive nervous system disorder, which means that it increases over time. It starts with parts of the body suffering small tremors accompanied by stiffness and slowing movement.

This is a lot dependent on the genetics of the person. This occurs mainly when the nerve cells in the brain die out and dopamine is lost.

There are ways to keep the nervous system healthy. The best ways are to exercise regularly, get a lot of sleep and proper rest, prevent smoking, and have a balanced diet.

Main Differences Between Hormones and Neurotransmitters

1. The main difference between hormones and neurotransmitters is that hormones are chemicals used by the endocrine system for various organs or tissues, and neurotransmitters are chemical messengers to transfer information through the synaptic gap.
2. Hormones are found in both plants and animals. Neurotransmitters are found in animals only.
3. Hormones are transmitted via the bloodstream. Neurotransmitters travel in the synaptic gap.
4. Hormones control development, physical growth, cognitive ability, etc. Neurotransmitters are used only to transmit messages in the nervous system.
5. Hormones are slow and can even take days to act. Neurotransmitters are fast and work in milliseconds.

References

1. https://www.annualreviews.org/doi/abs/10.1146/annurev.ne.14.030191.001251?journalCode=neuro
2. https://books.google.co.in/books?hl=en&lr=&id=OWxLaKew8sQC&oi=fnd&pg=PP1&dq=hormones&ots=bRsmaFXYnA&sig=UwVqH_KZy-YbpOsPI_vMaqJzlh0&redir_esc=y#v=onepage&q=hormones&f=false

Last Updated : 14 October, 2023