Some hormones act by

a. increasing the synthesis of enzymes,
b. converting an inactive enzyme into an active enzyme,
c. affecting only specific target organs,
d. all of these.

Question

Some hormones act by

a. increasing the synthesis of enzymes,
b. converting an inactive enzyme into an active enzyme,
c. affecting only specific target organs,
d. all of these.

Accepted Answer

Hi, everybody. Welcome back. Here's our next question. How do hormones trigger intracellular signaling pathways and affect cellular processes. A hormones bind to receptors on the surface of target cells. B hormones dissolve in the bloodstream and directly interact with target tissues. C hormones stimulate the release of neurotransmitters or D hormones bind to enzymes in the blood stream. So we're talking about hormones, triggering intracellular signal signaling pathways or signal transduction pathways that then affect cellular processes. The means by which they do that since in these cases, the hormones stay outside of the cell is choice. A hormones bind to receptors on the surface of target cells. It is important to note that some hormones do cross the plasma membrane and interact with receptors inside the cell. In which case, you might not necessarily have a pathway that could be the only thing that has to happen. But in each case, the hormone binds to a specific receptor to affect the cellular processes. Let's look at our other answer choices. And all of these BC and D are not the ways in which they interact because they don't involve this binding with the receptor. So in B, they don't dissolve in the bloodstream and interact directly with target tissues. In fact, many hormones are lipids and would not dissolve anyway. Uh Choice c hormones stimulate the release of neurotransmitters. Uh in general, that is not what they do. Again, they tend to bind to a receptor which might cause the release of some neurotransmitters if they have some sort of action in the brain, but they wouldn't stimulate the release of neurotransmitters just on their own. And choice D hormones bind to enzymes in the blood stream. Again, not the mechanism of their action, they bind to a hormone specific receptor. What are some of these cellular processes that they affect all sorts of things? Uh They can affect gene expression, enzyme activity, membrane permeability and causing secretion of certain substances. But again, they don't directly interact in these ways. As described in choices B through D, they cause these effects by first binding to a receptor. So choice, a hormones bind to the receptor of receptors on the surface of target cells is our answer to how hormones trigger intracellular signaling pathways. See you in the next video.

Some hormones act by a. increasing the synthesis of enzymes, b. converting an inactive enzyme into an active enzyme, c. affecting only specific target organs, d. all of these.

Verified Solution

Key Concepts

Hormonal Action Mechanisms

Enzyme Activation

Target Specificity