All of the following are true of the zebra mussels found in the great lakes except:
a. zebra mussels are having are having a negative impact on the native population of mussels in the region.
b. they were unintentionally introduced to the great lakes by humans.
c. zebra mussels have caused a great deal of environmental damage to the area.
d. people of the great lake region are benefitting from the economic advantages of having zebra mussels in the region.

Which of the following is a difference between a food chain and a food web? selected: a. food webs contain both plants and animals. food chains only contain animals.this answer is incorrect. b. food webs show energy transfer. food chains show which animal eats which animal. c. food webs separate organisms by tropic level. food chains do not. d. food webs are a complex patterns of energy flow. food chains only show one line of energy flow.

New york city has 2,181 inhabitants per square mile. the state of alaska has 1.03 inhabitants per square mile. ecologists would say alaska has a low exponential growth population density birth rate carrying capacity

1. variations in a population of moths allow for some of its members to be able to adapt to environmental changes. the better adapted of the moths will be able to survive the change and thus prevail as the “fittest” of the species. (a) describe three mechanisms in which variation can occur within a species population. (b) explain which mechanism or mechanisms would be responsible for the survival of a population of peppered moths better than white moths in an environment affected by industrial soot. justify your answer.