Throckmorton
Lifer
Consciousness is a philosophical debate. One can argue that a hydrogen atom has consciousness, it knows everything it needs to function as a hydrogen atom and does so quite flawlessly. Some also believe our consciousness is just the collective of individual pieces that form us. Not sure how far down the hole I'm willing to go yet, but I do believe everything has some level of consciousness and it's really arbitrary to compare them since they're so vastly different in the way they interact with the universe around them.
On any level you or I are capable of understanding so far, yes, that doesn't mean they don't have a consciousness.
Consciousness is a product of the thought processes of a physical brain. Creatures with different levels of intelligence have different degrees of consciousness. A plant has none because a plant has no brain whatsoever or even a nervous system. Even if consciousness had some nonphysical property in addition to the electronic functioning of the brain, plants don't have the brain to begin with.