Abiologist studying a desert ecosystem observes that the population of a lizard species increases following particularly hot, dry period that causes a snake population to decline. what could the biologist hypthesize about the roles of these two species?

a) the lizard preys on the snake

b) the lizard is a parasite of the snake

c) the snake and lizard use the same limiting resource

d) the snake is a keystone species in the ecosystem.

Aperson with age is more likely to catch diseases that healthy people usually don’t catch.what are these infections called?

Subduction zones form when an oceanic plate collides with another oceanic plate or continental plate. the continental crust is lighter and less dense than oceanic crust. continental crust's density is approximately 2.7 grams per cubic centimeter. oceanic crust is thinner and the average density is about 3.3 cubic centimeters. when the two crustal plates converge the oceanic plate always bends and subducts beneath a continental plate. once the oceanic crust subjects, the rocks are subjected to changes in heat and pressure. because of this, we would expect to find rocks in the area of a subduction. a) clastic b) igneous c) metamorphic d) sedimentary

In trying to determine whether dna or protein is the genetic material, hershey and chase made use of which of the following facts? a) dna contains sulfur, whereas protein does not. b) dna contains phosphorus, whereas protein does not. c) dna contains nitrogen, whereas protein does not. d) dna contains purines, whereas protein includes pyrimidines.