What is the name of the messenger molecule that participates in endocrine communication?Group of answer choicesNeurotransmitterHormoneNeurohormoneGap junction

Step 1: Break Down the Problem

To determine the correct answer, we need to analyze each option provided in the context of endocrine communication.

Step 2: Relevant Concepts

1. Neurotransmitter: A chemical substance that transmits signals across a synapse in the nervous system.
2. Hormone: A chemical messenger produced by endocrine glands, released into the bloodstream to regulate various functions in distant organs.
3. Neurohormone: A type of hormone that is released by neurons into the blood and influences the activity of distant organs, often linking the nervous system and the endocrine system.
4. Gap junction: Specialized intercellular connections that allow for direct communication between adjacent cells, not a molecule.

Step 3: Analysis and Detail

• Neurotransmitter: Not relevant to endocrine communication as it mainly acts locally on synapses.
• Hormone: This is a well-known messenger in the endocrine system; hormones can travel long distances through the bloodstream to affect target organs.
• Neurohormone: While also related to communication, it is specifically released by neurons and while it fits the broader category, it might not be as universally recognized as hormones in general endocrine communication.
• Gap junction: Incorrect as this doesn't involve a messenger molecule but rather a physical connection between cells.

Step 4: Verify and Summarize

Given the definitions and roles of each option, the most appropriate term that refers to a messenger molecule in endocrine communication is "Hormone".

Final Answer

Hormone is the name of the messenger molecule that participates in endocrine communication.