Examlex
What happens when a main-sequence star exhausts its core hydrogen fuel supply?
Natural Chemicals
Substances produced by living organisms found in nature that are not man-made or synthesized.
Synthetic Materials
Manufactured substances made from chemical synthesis, rather than those made from natural resources.
Hormesis
A biological phenomenon where a low dose of a harmful substance has a beneficial effect, while a high dose is toxic.
Endocrine System
A network of glands that produce and release hormones to regulate various bodily functions.
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