Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
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Question: Ultrasound, a diagnostic technology, uses high-frequency vibrations transmitted into any tissue in contact with the transducer.

Answer: What diagnostic technology uses high-frequency vibrations transmitted into any tissue in contact with the transducer?


Question: Tight junction is the term for a watertight seal between two adjacent animal cells.

Answer: What is the term for a watertight seal between two adjacent animal cells?


Question: Individuals do populations gain through births and immigration.

Answer:
What do populations gain through births and immigration?