Given a scientific question and its correct answer, generate supporting facts for the answer. This supporting fact can be an explanation for the answer to the given question.
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Question: Question: Breeding in birds occurs through an internal type of what process? Answer: fertilization

Answer: Breeding in birds is through internal fertilization, where the egg is fertilized inside the female.

Question: Question: What do the liver, gallbladder, and pancreas contribute that aid in digestion? Answer: chemicals

Answer: The liver, gallbladder, and pancreas contribute chemicals that aid in digestion.

Question: Question: Mass and volume are examples of what kind of properties? Answer: extensive properties

Answer:
Mass and volume are examples of extensive properties.