Determine whether the statement is true or false, and why. “hormones bond to a receptor protein to enter a cell and stimulate a response.” a. false, it should read “hormones bond to a receptor protein to stimulate a response inside a cell.” b. true c. false, it should read “hormones bond to a synaptic vesicle to enter a cell and stimulate a response.” d. false, it should read “hormones bond to a synaptic vesicle to stimulate a response inside a cell.”

Option A

Hormones work by two modes, either they enter the cell and bind to intracellular receptor or they bind to receptors present on the plasma membrane itself. If the hormone binds to the extracellular receptor, then it won’t enter the cell. But it will make changes in structure of the receptor and cascade of reactions will start inside the cell. Therefore, this statement is incorrect. The statement in option A makes perfect sense.

Option C and D are incorrect because it is not necessary that hormones bind to synaptic cleft. Also, they would not bind to anything to enter the cell. Thus, the statements are incorrect.

is called echinoderms