Given a scientific passage and an answer, generate a question for the given answer.

Q: Passage: Although most of a cell's DNA is contained in the cell nucleus, mitochondria have their own DNA. Mitochondria also have the machinery to manufacture their own RNAs and proteins. The human mitochondrial DNA sequence has 16,569 base pairs encoding 37 total genes: 22 tRNA genes, 2 rRNA genes, and 13 peptide genes. The 13 mitochondrial peptides in humans are integrated into the inner mitochondrial membrane, along with proteins encoded by nuclear genes. Answer: nucleus

A: Where is most of the cell's dna contained?
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Q: Passage: Are you on the basketball team? Are you a cheerleader? Do you play an instrument in the band? Your niche would be your role or place in the school. Organisms also each have their own niche in the ecosystem. Is an organism a producer or a consumer? How does the organism interact with other organisms? Is the organism involved in any symbiotic relationships?. Answer: niche

A: An organism's unique role in the ecosystem is called its what?
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Q: Passage: Sending humans to the seafloor is expensive and dangerous. Having to return humans safely to the surface limits what a mission can do. Remotely operated vehicles , or ROVs, allow scientists to study the deep without going to the seafloor. These small vehicles carry cameras and scientific instruments. ROVs were used to study inside the Titanic . This would have been far too dangerous for a manned sub to enter. Scientists control ROVs electronically with sophisticated operating systems. Answer: remotely operated vehicles

A:
What do scientists use to study the deep without going to the seafloor?
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