Given a scientific passage and an answer, generate a question for the given answer.
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Question: Passage: Figure 14.3 The Tongue The tongue is covered with small bumps, called papillae, which contain taste buds that are sensitive to chemicals in ingested food or drink. Different types of papillae are found in different regions of the tongue. The taste buds contain specialized gustatory receptor cells that respond to chemical stimuli dissolved in the saliva. These receptor cells activate sensory neurons that are part of the facial and glossopharyngeal nerves. LM 1600. (Micrograph provided by the Regents of University of Michigan Medical School ©️ 2012). Answer: papillae

Answer: What is the name of the small bumps that contain taste buds and covers the tongue?

Question: Passage: You can tell that this sponge is saturated with water because when it is squeezed, the water pours out. When something is saturated with water, it already holds as much water as possible. Compounds called hydrocarbons, which contain only carbon and hydrogen, can also be saturated, but not with water. Answer: hydrocarbons

Answer: What compounds contain only carbon and hydrogen?

Question: Passage: Most aquatic organisms do not have to deal with extremes of temperature or moisture. Instead, their main limiting factors are the availability of sunlight and the concentration of dissolved oxygen and nutrients in the water. Answer: availability of sunlight

Answer:
Besides the concentration of dissolve oxygen and nutrients in the water, what other factor limits aquatic organisms?