<span><span>a. </span>Reproducing</span>
f. obtaining
energy
d.
maintaining structure
Why do these
three illustrate the great challenge for every species.
<span><span>
1. </span>Reproduction, is as vital for an entire race to survive. It prolongs
their generation onwards and offspring to the next centuries to pass by.</span>
<span><span>
2. </span>Obtaining energy. In both humans and animals, even plants is a
challenge because these creatures need to work in order to obtain these need
resource from food –preys.</span>
<span><span>
3. </span><span>Maintaining structure. For the living organisms to still exist they
need to keep themselves intact. Combating diseases and having nutrition. This is
a by-product of having energy. </span></span>
Answer: A
Explanation: Diffusion is important to cells because it allows them to gain the useful substances they require to obtain energy and grow, and lets them get rid of waste products. This table shows examples of substances required by cell and associated waste products.
A cellular membrane separates the interior of all cells from the outside environment.