The necromorphs possess dead bodies, the flood possess both living and dead, I think.
It's not really coded into the games, but it's implied strongly. The only example I can think of off the top of my head is in Halo 2, when playing as the Arbiter and you realize flood have assaulted the heretic base and the lead elite says "we should have brought weapons to burn these bodies." I'm sure there are other examples, though it may be the recently deceased, and I'm sure living are better.
Plus the flood have Gravemind, which owns all, though if the living Gravemind was destroyed, I think the flood could survive to build a colony, and a new gravemind.
It's not really coded into the games, but it's implied strongly. The only example I can think of off the top of my head is in Halo 2, when playing as the Arbiter and you realize flood have assaulted the heretic base and the lead elite says "we should have brought weapons to burn these bodies." I'm sure there are other examples, though it may be the recently deceased, and I'm sure living are better.
Plus the flood have Gravemind, which owns all, though if the living Gravemind was destroyed, I think the flood could survive to build a colony, and a new gravemind.