Question

what is adrenaline and how adrenaline is secreted directly into the blood?

Answer 1

Dear student,

Adrenaline, also known as epinephrine, is a hormone secreted by the adrenal medulla. The adrenal medulla consists of masses of neurons that are part of the autonomic nervous system(symapathetic branch). Adrenal medulla releases their neurotransmitters directly into the blood, instead of releasing them at the synapse. Thus, even after being a part of the nervous system , the adrenal medulla functions as an endocrine gland.
The release of the hormone adrenaline is triggered by nervous stimulation in response to any mental or physical stress. The hormone binds to the adrenergic receptors which is present on plasma membrane of many cells.

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