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

Passage: When a fluorine atom gains an electron, it becomes a negative fluoride ion. Answer: fluoride ion
When a fluorine atom gains an electron, it becomes a negative what?

Passage: The hemisphere that is tilted away from the Sun is cooler because it receives less direct rays. As Earth orbits the Sun, the Northern Hemisphere goes from winter to spring, then summer and fall. The Southern Hemisphere does the opposite from summer to fall to winter to spring. When it is winter in the Northern hemisphere, it is summer in the Southern hemisphere, and vice versa. Answer: direct rays
The hemisphere that is tilted away from the sun is cooler because it receives less what?

Passage: The kidneys are a pair of bean-shaped organs just above the waist. They are important organs with many functions in the body, including producing hormones, absorbing minerals, and filtering blood and producing urine. Answer: kidneys
What is the pair of bean-shaped organs that filters blood and produces urine?