Which of the following hormones exerts its action by interacting with a receptor at the cell surface?

Question

A.  insulin
B.  cortisol
C.  testosterone
D.  estrogen
E.  progesterone

Clarify Question
What is the key concept addressed by the question?
What type of thinking is required?

Gather Content
What do you already know about hormones? What other information is related to the question?

Choose Answer
Given what you now know, what information is most likely to produce the correct answer?

Reflect on Process
Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?

Answer 1

A.  insulin

Clarify Question
What is the key concept addressed by the question?
        · Which hormone needs a cell surface receptor?
What type of thinking is required?
            o This is an analyze question because you have to consider how these hormones differ from each other and how they interact with receptors differently.

Gather Content
What do you already know about hormones? What other information is related to the question?
        · Hormones are signaling molecules that travel via the bloodstream to target tissues where they bind to receptors to initiate cellular responses. There is two types of receptor binding in hormones- binding that occurs at receptors on the cell surface and binding the occurs on intracellular receptors. Hydrophobic (or lipophilic) molecules can diffuse across the phospholipid bilayer of cell membranes. Steroid hormones are cholesterol based and can diffuse directly through cell membranes. Protein hormones such as insulin cannot; they must bind to receptors on the cell surface.

Choose Answer
Given what you now know, what information is most likely to produce the correct answer?
        · Cortisol, testosterone, estrogen, and progesterone are all steroid hormones. Thus these hormones do not need cell-surface receptors. Insulin is a protein that cannot diffuse across the cell membrane and thus needs cell-surface receptors to bind to.

Reflect on Process
Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?
       o Answering this question correctly depended upon understanding the function of hormone-receptor binding and realizing that some hormones can cross the cell membrane while others cannot. If you got the answer correct, great! If not, where did you go wrong? Did you forget that cortisol is a steroid hormone? Did you forget that steroid hormones can diffuse across the cell membrane and thus do not need a cell-surface receptor?