1. natural selection acts on existing traits because you can not evolve into something you didn't have
2. original structures evolve to accomplish new function in order to survive
The factor that does not help determine whether a volcanic eruption will be explosive or relatively quiet is the composition of the lava.
On the other hand, the composition of the magma, the temperature of the magma, and the amount of dissolved gases in the magma are quite important for determining this.
Answer:
B. The membrane lets certain substances move across it freely, while others must move through a “gate”.
Explanation:
Selective permeability is a property of cellular membranes that only allows certain molecules to enter or exit the cell. This is important for the cell to maintain its internal order irrespective of the changes to the environment. For example, water, ions, glucose and carbon dioxide may need to be imported or exported from the cell depending on its metabolic activity. Similarly, signaling molecules may need to enter the cell and proteins may need to be released into the extracellular matrix. The presence of a selectively permeable membrane allows the cell to exercise control over the quantum, timing and rate of movement of these molecules.
mRNA would be CCAUCCUUUGGG
tRNA would be GGUAGGAAACCC
Magnesium Phosphate is the answer