7.
A farmer observed that an increase in a field's soil nitrogen content was
followed by an increase in producer productivity. What does this observation
most likely indicate about the relationship between nitrogen and the producers
in the field?
a. Nitrogen was a biotic factor.
b. Nitrogen was a limiting factor.
c. Nitrogen became a surplus resource.
d. Nitrogen became a selection pressure.
A species of snapping turtles has a tongue that resembles a worm. The
tongue is used to attract small fish. Which best describes the interaction
between the fish and the snapping turtle?
a. Predation
b. Symbiosis
c. Parasitism
d. Competition