Consider the figure illustrating the two major classes of hormones and their actions. Which class of hormones would you expect to be ideally suited for long-term processes such as growth and development?
A) protein hormones, because they can relay messages
B) steroid hormones, because they can turn specific genes on or off
C) protein hormones, because they cannot cross cell membranes
D) steroid hormones, because they can diffuse across cell membranes
B
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