2. a) a dog breathes out co, and a tree releases 02. how are the dog and the tree connected in the
oxygen cycle? (2 points)

When a dog breathes out CO, the plants absorb it. The tree releases oxygen which helps us breathe. The dog is a fueler of oxygen. The CO from the dog gets absorbed by the tree and releases oxygen.

Explanation: They are connected because the tree needs co2 to create o2 and the dog needs o2 to breathe. Without the dog the tree can't run its course and without the tree the dog can't breathe.

he forelimbs below belong to four species that descended in a direct line from the ancestral mammal shown above. of the four descendants shown, which species most likely appeared earliest in evolutionary history?