Question

What is the significance of the discovery of different hormone receptor types for the hormone epinephrine?
A.Two types of epinephrine hormone response elements were identified.
B. Different tissues responded differently to the presence of epinephrine.
C. It was discovered that slightly different forms of epinephrine (agonists)were secreted by the adrenal glands.
D. All target tissues for epinephrine possess all four types of epinephrine receptors.

Answer 1

Hint Hormones are chemical substances. Hormone first binds to receptors on the target cells then it forms the hormone receptor complex. The hormone does not have a direct role in the target cells but this hormone-receptor complex causes different response and alternation in the target cells. Hormone receptors are nothing but protein molecules. The main feature of the receptor is that each receptor acknowledges only one hormone. Glucagon receptors, androgen receptors, insulin receptors, etc are some examples of hormone receptors. These hormone receptors enable the transmission of signals.
Complete Step-by-step answer:
Generally, epinephrine is known as adrenaline. The epinephrine hormone is secreted by the medulla of the adrenal gland. Its main function is to increase cardiac output and glucose levels in the blood. This hormone is secreted mainly during an emergency situation and prepares the body either to fight that situation or run away from that particular situation. So, this hormone is known as the “Flight or Fight Response” to prepare the body for strenuous activity.
The action of epinephrine is a bit complex. Depending on the specific receptors and tissue where they occurred, epinephrine produces various responses. Epinephrine causes the narrowing of many blood vessels, it widens the blood vessels in the liver as well as the skeletal system. It increases the heartbeat and blood pressure levels. In the liver, it promotes the breakdown of glycogen into glucose. As a result of which the sugar level in the blood increases. Apart from these it also raises the level of circulating free fatty acids. These extra amounts of glucose and fatty acid in the body can be used in an emergency or dangerous situation.
Hence the correct answer is option B. Different tissues responded differently to the presence of epinephrine.
Note: Epinephrine is also prepared synthetically for clinical use. During cardiac arrest to stimulate heart activity epinephrine can be injected into the heart. Apart from this, it is used in the treatment of allergies, low blood pressure, glaucoma, and asthma.