Answer:
That is administered and controlled
Step-by-step explanation:
A variable is the condition or a product that may vary without the influence of any investigator. Such variables can be found abundantly in our daily lives, ranging from air to sunlight. Controlling such variables ensures the limitation of their influence on the outcome of an experiment. In connection to this experiment, the variables that are controlled are the mineral content in the water, the amount of bacteria food, the amount of light and the the constant temperature of 20 degrees C.
If not administered or these variables controlled, the experiment would not clearly explain the impact of caffeine on the heart beat of the water fleas as other variables may have influenced it. Thus variables are controlled to study the singular impact of any agent or effect.
Mutation is the only evolutionary mechanism that does little to change allele frequencies.
What happens is that the RNA<span> is synthesized from the template and RNA polymerase moves along the DNA, elongating the RNA transcript molecule; an enzyme forms the hydrogen bonds between the bases of the DNA strand and the complementary bases of the RNA molecule found in the nucleus.</span>
<span>Hope this helped !!</span>
B seasonal variations in climate tend to increase with distance from the equator
Food cant move unless psychically moved by a human so thats the potenial energy it is not stored any were.
