The answer is botany....... hope that helped
Answer: that veins have valves to prevent backflow and arteries don’t.
Explanation:
1. Survival fitness is the existence of organisms <span>that are best adapted to their environment, with the extinction of others.
2. A wooden fence is not considered a living thing. It might have living things growing ON it, but it's not living. It was once a living thing yes, but now, no.
3. The trunk on a tree is definitely a living thing. It's part of the tree after all.</span>
During the process of ossification, an existing tissue is replaced by bone.
Answer should be death rate
