Given a scientific question, generate a correct answer to it.

Q: What structure consists of an outer layer of cells called the trophoblast and an inner cell mass called the embryoblast?

A: blastocyst
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Q: Amino acids are made by which kind of plastid?

A: leucoplasts
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Q: Earthquake waves that travel trhough underground rocks in all directions are known as?

A:
secondary waves
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