What does the arrow mean in a food chain?

Plz ! ive been stuck on this forever

What two factors does carrying capacity compare? population size and resource use population growth and resource availability resource use and time population size and time

Just a quick question. will give pointswhat is the root word of "blood."it is written in my homework as hemat(o) : blood. so, should i write that the root word as hemat or hemato or hemat(o). i'm really confused.