Sempiternal wrote:
It certainly would.
That makes me wonder... Are jellyfish sentient since they don't have brains?

I realized that I question sentience quite a lot.
They are probably as sentient as insects, probably to a lesser degree. They are guided by an instinct, not necessarily a will, to survive, thrive and reproduce. Insects, which are probably more complicated organisms than jellyfish, do not even feel pain. Creatures like arthropods and cnidarians I liken more to machines or beings running off adaptive or born-in programming.
Of course in our day to day lives we like to personify all these creatures with humanoid characteristics but in reality they are very alien, compared to us and mammals at least. For example, social insects like ants are probably the most organized, harmonious insect within their hives and have even been observed adapting and changing to outside stimuli in labs but I still wouldn't consider it the same as the type of learning a dolphin or dog has the potential for. Creatures like spiders and cockroaches can to a degree identify danger but again, its part of programming and instincts. As a baby we have to be taught that fire burns, stingy bugs sting etc. Not the case with these creatures. A preying mantis spots his or her prey but it doesn't think, hesitate, feel fear or guilt.
So to answer your question: No, probably not. Are flowers sentient?
Of course with all that said, I love and respect nature. I go out of my way to not kill centipedes, wasps, and other creepy crawlies. I'm not the most pious person but I believe all animals are pure, "free of sin" to quote a line said by Father Zosima in the Brothers Karamazov. That makes them special to me. My grandmother use to upset me and said all animals went to hell, she is very fundamentalist and a pentecostal. I really think the opposite now, if there is a heaven, animals get free access because they are the most godly and pure, even the lowly mosquito. She doesn't choose to suck blood but does it to ensure her offspring's survival. I've heard this multiple times from bible thumpers and its hilarious because even the Bible says that all animals serve God and in the Eden of the old testament they were not predatory, even the lions. Man himself, going against God's wish by indulging himself in the fruit of knowledge is what causes animals to become predatory, suck blood and behave in any way that is detrimental to us. Huh fancy that. Teachers and religious people even told me animals didn't have souls even though, again, the bible directly states that they all do and choose their forms and destiny.
I'd like to state I'm pretty much agnostic/atheist so don't offense to that blurb.