Dutch elm disease is a disease of elm trees caused by a fungus. The fungus lives off water and nutrients from the tree. It spreads through water-conducting vessels in the tree. Gum forms within these vessels in response to the fungus, and the tree weakens and dies. Beetles spread the fungus from infected trees. What is the relationship
between the fungus and the elm tree?
A. predator-prey
O
B. mutualism
C. commensalism
D. parasite-host

How do you think earths interior affects what is happening on the surface? 2. how do fossils support the continental drift hypothesis? 3. how does sea- floor spreading support the hypothesis of continental drift? 4.what do scientists observe when they studied the magnetic fields of rocks on the sides of mid-ocean ridges? 5. what is a tectonic plate ? 6. explain mantle convection 7.how can movements of the continents affect earths climate? 8. what occurs during drifting?