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

Q: Passage: Tuberculosis (TB) is a common and often deadly disease caused by a genus of bacterium called Mycobacterium . Tuberculosis most commonly attacks the lungs but can also affect other parts of the body. TB is a chronic disease, but most people who become infected do not develop the full disease. Symptoms include a cough, which usually contains mucus and coughing up blood. Answer: mycobacterium

A: What type of bacteria causes the disease called tuberculosis?
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Q: Passage: In sexually reproducing organisms, parents pass a copy of each type of chromosome to their offspring by producing gametes. When gametes are fertilized and form offspring, each has a unique combination of chromosomes and genes from both parents. The inherited gene combination determines the characteristics of the offspring. Answer: chromosome

A: In sexually reproducing organisms, parents pass a copy of each type of what to their offspring by producing gametes?
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Q: Passage: When light hits rods and cones, it causes chemical changes. The chemical changes start nerve impulses. The nerve impulses travel to the brain through the optic nerve . Answer: optic nerve

A:
Through what does the nerve impulses travel to the brain?
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