“Nerve terminals release chemicals” is the postulate put foh by:
**Core Concept**
The postulate that nerve terminals release chemicals to communicate with other neurons or cells is based on the concept of neurotransmission. Neurotransmission is the process by which neurons transmit signals to other neurons, muscles, or glands through the release of chemical messengers called neurotransmitters. This process is essential for various physiological functions, including muscle contraction, hormone regulation, and sensory perception.
**Why the Correct Answer is Right**
The correct answer is based on the discovery of neurotransmitters by Otto Loewi in 1921. Loewi demonstrated that the vagus nerve releases a chemical that slows the heart rate, which is now known as acetylcholine. This discovery led to the understanding that nerve terminals release neurotransmitters into the synapse, where they bind to receptors on adjacent cells, transmitting signals. The release of neurotransmitters is mediated by the vesicular release machinery, which involves the fusion of vesicles containing neurotransmitters with the presynaptic plasma membrane.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not specify the correct postulate related to neurotransmission.
**Option B:** This option is incorrect because it does not mention the release of chemicals by nerve terminals, which is the key concept being tested.
**Option C:** This option is incorrect because it is too vague and does not specify the postulate related to neurotransmission.
**Clinical Pearl / High-Yield Fact**
Remember the acronym "FREED" to associate with the key concepts of neurotransmission: Facilitation (release of neurotransmitters), Release (of neurotransmitters from vesicles), Excitation (of postsynaptic receptors), Efficacy (of neurotransmitters in transmitting signals), and Elimination (of neurotransmitters from the synapse).
**Correct Answer:** A.