That would be the ER (endoplasmic reticulum) and the Golgi apparatus.
Answer:
I am getting DNA samples from these people because they are prime suspects at the scene (at the exact time and place). Besides, if there is any evidence left over; it should be stored and used for further research.
Explanation:
Yes; this occurs when an organism has a varied diet. Humans are an example of this: When eating plants, we are on one trophic level; and, when eating meats, we are on another.
Hope this helps!
Answer:
I would say Hydrogen because it makes 51% of the cell constituents.