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

Q: Passage: Figure 7.22 Osteoporosis Osteoporosis is an age-related disorder that causes the gradual loss of bone density and strength. When the thoracic vertebrae are affected, there can be a gradual collapse of the vertebrae. This results in kyphosis, an excessive curvature of the thoracic region. Answer: osteoporosis

A: What is the age-related disorder that causes the gradual loss of bone density and strength?
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Q: Passage: Like a blanket on a sleeping person, greenhouse gases act as insulation for the planet. The warming of the atmosphere is because of insulation by greenhouse gases. Greenhouse gases are the component of the atmosphere that moderate Earth's temperatures. Answer: insulation

A: Like a blanket on a sleeping person, greenhouse gases act as what for the planet?
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Q: Passage: Cellular respiration uses oxygen in addition to glucose. It releases carbon dioxide and water as waste products. Cellular respiration actually "burns" glucose for energy. However, it doesn't produce light or intense heat like burning a candle or log. Instead, it releases the energy slowly, in many small steps. The energy is used to form dozens of molecules of ATP. Answer: oxygen

A:
In addition to glucose, what gas is used during cellular respiration?
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