Practice free →
HomeSMLE (Saudi Medical Licensing)PhysiologyThe Endocrine System › A hormone that stays at a high level in the bloo…

A hormone that stays at a high level in the bloodstream causes its target cells to do what?

AIncrease their number of receptors for it
BDecrease their number of receptors for it
CConvert the hormone into an inactive form
DRelease a second messenger into the blood
Answer & Solution
Correct answer: B. Decrease their number of receptors for it
1. A target cell responds only in proportion to the receptors it carries for that hormone. 2. Chronically high hormone levels make the cell cut its receptor number, a process called downregulation. 3. That leaves the cell less reactive to the excess hormone. 4. Upregulation is the mirror image and follows chronically low hormone levels. 5. Second messengers stay inside the cell, so they are never released into blood as a way of coping with excess. _Source: OpenStax Anatomy and Physiology (CC BY 4.0), Ch 17 "The Endocrine System", section 17.2 Hormones_
Solve this in the app — SMLE (Saudi Medical Licensing) practice & 24k+ MCQs →
Related questions