instruction:
Given a scientific passage and an answer, generate a question for the given answer.
question:
Passage: All the atoms of a given element have the same number of protons in their nucleus, but they may have different numbers of neutrons. Atoms of the same element with different numbers of neutrons are called isotopes. Many elements have one or more isotopes that are radioactive. These isotopes are called radioisotopes . Their nuclei are unstable, so they break down, or decay, and emit radiation. Answer: protons
answer:
All the atoms of a given element have the same number of what in their nucleus, though they may have different numbers of neutrons?

question:
Passage: Although lots of symbiotic relationships help both organisms, sometimes one of the organisms is harmed. When that happens, the organism that benefits, and is not harmed, is called a parasite . This type of relationship is known as parasitism. Answer: parasite
answer:
Although lots of symbiotic relationships help both organisms, sometimes one of the organisms is harmed. when that happens, the organism that benefits, and is not harmed, is called a what?

question:
Passage: Besides their strength, another pro of electromagnets is the ability to control them by controlling the electric current. Turning the current on or off turns the magnetic field on or off. The amount of current flowing through the coil can also be changed to control the strength of the electromagnet. Answer: electric
answer:
Electromagnets can be controlled by controlling what type of current?