Hey there!
Based on your options above, your answer seems to be (<span>increase resistance to disease).
This was never a reason to actually increase the disease of creating a Hybrid. It clearly makes no sense. This would include that your answer would be (c).
Hope this helps.
~Jurgen</span>
I would say, C. Because an controlled variable is an experimental element which is constant and unchanged throughout the course of the investigation.
We all know that heat is energy, and if too much energy is applied to anything, it is denatured. pH is a denaturing agent since it changes the protein, essentially by using Hydrogen (part of the bonds) as a counteract. Amphiphilic detergents are not beneficial for proteins because they’re responsible for breaking covalent bonds. Mercaptoethanol, as the name says, has ethanol, which reduces proteins into nonexistence.
Species.
The answer for that is easy to find on google. You should have just googled it.
A chemical change is a change in which the composition of the matter is changed at the molecular level, most chemical changes are not easily irreversible, for example, an egg being cooked, the egg changes from its liquid like state to a solid, and it is not possible to revert it back to its original change. The egg itself is changed in this case.
A physical change on the other hand however, is only changing the substance of a matter, not its composition, this is usually easily reversible. For example, water turning into ice, the water's substance changed from its liquid state to its solid state, it is still water, and it can easily be turned back into water by heating it.
Sorry for the long explanation,
Hope this helps!