Answer:
Proteins.
Explanation:
They are called membrane proteins.
Evolution is the theory of slow change during long time periods.
Answer:
Classification system changes because the scientists find new evidence in their studies.
Explanation: The world is always changing and growing and dying as well as developing, so over time things change. For example, as you grow up do you stay the same? No, you notice the physical changes happening, well thats sort of like how the earth and its ways are always changing as well.
Prostaglandin similarity with hormones is in the effect they achieve by binding to the receptors. Their effects are mediated by paracrine or autocrine mechanisms. Another hormone characteristic is the ability to stimulate adenylate cyclase activity, producing cAMP as the second messenger.
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On the other hand, prostaglandins differ from hormones in that they are not produced at a specific place but in many different places throughout the body. Also, the metabolic degradation of prostaglandins is very rapid.</span>
<span>descriptions of the number, size, and arrangement of parts of the organism.</span>