Answer:
Answer is C.
Explanation:
A. The vessel length is pretty much constant. The body can't length or shorten blood vessels.
B. Blood viscosity is also fairly constant because the composition of blood cannot change quickly enough to change resistance as needed.
C. This is the main way resistance is controlled. The smooth muscle surrounding blood vessels can rapidly respond to hormonal or metabolic stimuli and contract/relax to adjust diameter.
D. Again, temperature is fairly constant in the body and would not be a good way to alter resistance.
Answer:
Nutrients and other materials from the environment are absorbed through mycelia. The branching mycelia have a high surface-area-to-volume ratio which allows the absorption of nutrients to be more efficient. Fungi may even digest nutrients by releasing enzymes into the environment.
Explanation:
I have a strange feeling that this isn't the answer you were looking for.
The answer is nucleic acids because they contain DNA.
If the temperature is too high, it can alter the structure of the enzyme and make it unable to bind to the substrate. But, if the temperature is too low the chance for the enzyme to collide with the substrate will be lower too. The enzyme works best in the highest temperature before its structure changed.
The data from the experiment should look like a bell. There is an optimal temperature for the enzyme and increasing/decreasing from that temperature will result in reduced reaction speed.
