Answer:
It is used by every living cell
Explanation:
Essentially, a control variable is what is kept the same throughout the experiment, and it is not of primary concern in the experimental outcome. Any change in a control variable in an experiment would invalidate the correlation of dependent variables (DV) to the independent variable (IV), thus skewing the results.
Answer:
C. Testes
Explanation:
Testes are only seen in males. It is an organ that produces spermatozoa (male reproductive cells).
Photosynthesis is when plants use sunlight to synthesize food from carbon dioxide. Plants are autotrophs (they make their own food) and the food they synthesize creates carbohydrates, so the correct answer is D - autotrophs produce carbohydrates.
Hope this helps.
