Semipermeable means only certain substances can pass through. I imagine you are talking about cell membranes which are semipermeable. This means vital things like oxygen and nutrients are able to pass through the membrane, while not allowing everything to enter the cell
The answer is B
C pairs with G, T pairs with A but in RNA T is replaced with U so A pairs with U
Answer:
habitat
Explanation:
habitat is part of the ecosystem
niche describes ahow different organisms are linked
Pork and beef insulins are similar to human insulin, differing only in one or a few amino acids. However, even a slight difference is enough to elicit an allergic response in some people. To overcome this problem, researchers looked for ways to make insulin that would more closely resemble human insulin.