Given a scientific passage and an answer, generate a question for the given answer.
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Question: Passage: Note the Pattern Few binary molecular compounds of nitrogen are formed by the direct reaction of the elements. At elevated temperatures, nitrogen reacts with highly electropositive metals to formionic nitrides, such as Li3N and Ca3N2. These compounds consist of ionic lattices formed by M n+ and N3 ions. Just as boron forms interstitial borides and carbon forms interstitial carbides, with less electropositive metals nitrogen forms a range ofinterstitial nitrides, in which nitrogen occupies holes in a close-packed metallic structure. Like the interstitial carbides and borides, these substances are typically very hard, high-melting materials that have metallic luster and conductivity. Nitrogen also reacts with semimetals at very high temperatures to produce covalent nitrides, such as Si3N4 and BN, which are solids with extended covalent network structures similar to those of graphite or diamond. Consequently, they are usually high melting and chemically inert materials. Ammonia (NH3) is one of the few thermodynamically stable binary compounds of nitrogen with a nonmetal. It is not flammable in air, but it burns in an O2 atmosphere: Equation 22.30. Answer: ammonia

Answer: What (nh3) is one of the few thermodynamically stable binary compounds of nitrogen with a nonmetal?

Question: Passage: Opposite charges attract, and like charges repel. Answer: attract

Answer: What do opposite charges do to one another?

Question: Passage: Animal Cells versus Plant Cells At this point, you know that each eukaryotic cell has a plasma membrane, cytoplasm, a nucleus, ribosomes, mitochondria, peroxisomes, and in some, vacuoles, but there are some striking differences between animal and plant cells. While both animal and plant cells have microtubule organizing centers (MTOCs), animal cells also have centrioles associated with the MTOC: a complex called the centrosome. Animal cells each have a centrosome and lysosomes, whereas plant cells do not. Plant cells have a cell wall, chloroplasts and other specialized plastids, and a large central vacuole, whereas animal cells do not. The Centrosome The centrosome is a microtubule-organizing center found near the nuclei of animal cells. It contains a pair of centrioles, two structures that lie perpendicular to each other ( Figure 4.15). Each centriole is a cylinder of nine triplets of microtubules. Answer: centrosome

Answer:
What is the microtubule-organizing center found near the nuclei of animal cells?