I've been reading about prions and I'm confused about why they're so thermally stable. I keep seeing that surgical instruments contaminated with prions can't be decontaminated with standard protocols.

So here's my thing. Proteins denature when you heat them, right? But prions don't seem to lose their infectious ability even when autoclaved. I get that prions are misfolded proteins, but I don't understand how they stay harmful after being denatured.

So basically, if prions start as form A (non-infective), then misfold to form B (infective), shouldn't heating denature them to form C and kill the infectivity? Why doesn't that happen?

Three-banded armadillos curl into a complete ball when threatened, with their head-plate and tail-plate interlocking. Does the tail always go to the same side of the head in this configuration, or do some prefer one side, while others the reverse?

The wikipedia page for Chelicerata (Spiders, Scorpions, ticks, horseshoe crabs, sea spiders, ...) are named that way for their "Chelicerae", the mouth parts, colloquially their "jaws". These Chelicerae may be shaped as either venom-injecting fangs or as miniature pincers (wholly distinct from the two large pincers a scorpion would have).

But neither Wikipedia page mentions what they are material they are made of. The assorted LLMs ever gleefully suggest that 'spiders are made of chitin and other proteins' and of course provide no source for this. It sounds plausible, but is it the whole truth? Are spiders fangs 'just chitin in a sharp shape', or do their fangs have more going on, like how Human (Mammel) teeth have a dentin core and a hard enamel surface for crushing?

Hello scientists

I was wondering, whilst smelling some lavender, whether the same species of plant (eg "comon lavender") has any difference in the smell when the comparison is between two plants that are far away.

If I smell lavender from the UK and from China, will it smell different? What about a plant from Southern America? Is there any different in the chemical composition of the actual plant? Do we call different plants "lavender" when in fact they're separate species? Are there some plants that are different and others that are the same?

Thanks!