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Answer:
The differences in gravity, craters on the moon and unknown materials.
Explanation:
These would all be helpful to consider.
C. The presence of predators could cause natural selection because it would mean survival of the fittest.
1. The oxygen requirements of an animal cannot be met by the process of diffusion as diffusion is a very slow process. To overcome this, multicellular organisms have specialized cells and tissues for performing various necessary functions of the body such as intake of oxygen and food.
2. What criteria do we use to decide whether something is alive? Any visible movement such as walking, breathing, or growing is generally used to decide whether something is alive or not. However, a living organism can also have movements, which are not visible to the naked eye.
3. An organism uses outside raw materials mostly in the form of food and oxygen. The raw materials required by an organism can be quite varied depending on the complexity of the organism and its environment.
4. The various processes essential for maintaining life are nutrition, respiration, transportation, excretion, control and coordination.
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