The correct answer is b, antigens
Answer:
C) It involves interactions between biotic and
abiotic factors.
Explanation:
Ecosystems need energy imput, need both consumers and producers, and can exist on land, lakes, rivers and oceans.
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.
The neuroendocrine system combines brain actions and and other bodily functions. In the brain, the hypothalamus maintains the balance (homoestasis) which affects other functions of the body such as metabolism, regulating reproduction, utilization of energy, drinking and eating behavior, blood pressure and osmolarity.
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