Answer: D
Explanation:
Many unicellular organisms live in bodies of water and must move around to find food. Most often, they must obtain nutrients by eating other organisms. Plant-like protists, and some types of bacteria, can make their own food through photosynthesis.
Other biological molecules that contain the element of N would be nucleic acids such as DNA and or RNA. There are found in the nucleotides that constitute or make up these nucleic acids.
The air in Greg's house is like the cytoplasm of a cell because it is the gel-like material that surrounds the other parts of the cell.
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