Answer:
Neurotransmitter molecules
Explanation:
(SEE BELOW FOR FULL EXPLANATION ON WHAT NEUROTRANSMITTERS ARE AND WHAT THEY DO)
Chemicals known as neurotransmitters are created by neurons and transferred across the synaptic gap (the empty space between neurons). These chemicals then connect with certain receptors on the surface of the second neuron, causing it to transmit the signal to the third neuron or to have other specific consequences. Keep in mind that synapses are not always between two neurons. They might be situated between a neuron and a gland or a neuron and a muscle.
When molecules have completed their task, they separate from the receptor and are typically metabolized by enzymes. The remainder is then taken up by the first neuron, where it is later utilized to produce new transmitters.
Different neurons generate various neurotransmitters (or other cells). It's noteworthy to note that numerous receptor types with various functions may often be activated by a single kind of neurotransmitter. Many of them also have an impact on the body's other systems and are not just related to the nervous system. Some of the most significant neurotransmitters are listed below:
Adrenaline transmits signals between the neurons that control movement. It also affects other organs, including the heartbeat, respiration, bowel movement, and stomach discharge. It also speeds up the heartbeat and breathing.
Acetylcholine is a chemical that transmits signals from neurons to skeletal muscles. Additionally, it quickens bowel movements, decreases the pulse, and boosts stomach discharge.
Serotonin transmits signals between brain neurons. Its side effects include migraine, nauseousness, and vomiting.
Dopamine's effects include controlling movement, motivation, nausea and vomiting during breastfeeding (sometimes, two substances have the same effect, because neurons, that are responsible for the effect have different types of receptrs, which in this case have the same effect, as they activate the same cells).
Gamma-Aminobutyric Acid is abbreviated as GABA. This one is intriguing since it calms the nervous system and actually reduces cell activity when GABA receptors are activated. For instance, benzodiazepines are medications that work on the same receptors and serve the same purpose as GABA. Their effects—reduced stress, sedation, and sleep—are widely documented.
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Noting that there are several additional significant neurotransmitters as well as numerous others with less obvious roles, I simply included the most fundamental details for the most fundamental molecules. I hope that makes the key point clearer to you.
Thank you,
Eddie
