Question

All target cells _____.

1) have receptors to which hormones bind.
2) are found in the blood.
3) secrete hormones.
4) produce their own hormones

Answer 1

Target cells are affected by hormones because they possess specific receptors that match the hormone molecules. Hormones are secreted by endocrine glands and only influence cells with these receptors, which is why hormones have specific effects even though they travel throughout the body.

Step-by-step explanation:

All target cells have receptors to which hormones bind. This is because hormones work by causing changes in target cells by binding to specific hormone receptors.

Target cells can have cell-surface or intracellular receptors with a binding site that matches the hormone molecule, ensuring that each hormone affects only cells with receptors specific to that hormone.

For example, thyroid hormones have a wide-reaching effect on various tissue types, enhancing metabolic activity, because many cell types carry receptors for these hormones.

On the other hand, target cells do not necessarily secrete or produce hormones themselves; those functions are typically performed by endocrine glands.

Hormones like estrogen are secreted by these glands and travel through the bloodstream to reach their specific target cells. Despite reaching nearly every cell in the body, hormones only affect cells bearing the appropriate receptors, which is why not all cells respond to a particular hormone.