Test — Cumulative exam Answers

Read this passage about global fishing.Global consumption of large fish has led to an exploitation of fish populations. Overfishing has led to a decline in the populations of many species of large fish including North East Arctic Cod. The graph below shows the decline in the cod population.As the human population grows and countries continue to develop, the demand for large fish has been steadily increasing. Unfortunately, the average size of the cod has decreased because the fishing nets were designed to catch the large fish and the smaller individuals could escape more easily.What is most likely happening to the genetic variation of the population of North East Arctic Cod?

Which factors affect natural selection?

A primate species with a brain size of 1200 cc is discovered. From the information in the graph, what can be predicted about this species?

Read the following passage from the Biology Department at University of California, Berkeley.Northern elephant seals have reduced genetic variation because hunting by humans reduced their population size to as few as 20 individuals at the end of the 19th century. Their population has since rebounded to over 30,000, but their genes still carry the marks of this near extinction: they have much less genetic variation than a population of southern elephant seals that was not hunted as intensely.Which of the following best describes how the population has evolved?

What does a karyotype show?