1. Evolution CRCT Practice Questions

14. The structures shown below are _____ a. vestigial b. analogous c. heterologous d. homologous

15. d. homologous

16. How do mutations change populations over time? a.Most mutations are harmful and cause species to become extinct b.Most mutations cause abnormal disease in species c.Mutations generally have no effect on a population since they are simple changes in DNA d. Mutation can produce adaptations in organisms that help them survive better in their environment

17. D. Mutation can produce adaptations in organisms that help them survive better in their environment

18. What type of adaptation is shown in below? a. artificial selection b. Homologous structures c. camouflage d. mimicry Walking stick

19. c. camouflage

20. Natural selection can best be defined as the _____. a.elimination of the smallest organisms by the biggest organisms b.survival and reproduction of the organisms that occupy the largest area c.survival of the biggest and strongest organisms in a population d.survival and reproduction of the organisms that are genetically best adapted to the environment

21. d. survival and reproduction of the organisms that are genetically best adapted to the environment

22. A farmer sprayed his corn crop with an herbicide to kill the weeds in his field. Most of the weeds died from the herbicide, but a few were resistant and survived. The next year, the farmer used the same herbicide on his field. This time the herbicide did not work as well. The weeds seemed to be unaffected. Which best explains this situation? a.The herbicide caused a mutation in the weeds. b.The herbicide caused immunity in the weeds. c.A few weeds in the first population were immune to the herbicide and passed this trait on to the second generation. d.The weeds learned to fight off the herbicide.

23. c.A few weeds in the first population were immune to the herbicide and passed this trait on to the second generation.

24. Two individuals are unquestionably members of the same species if they: a. possess the same number of chromosomes. b. breed at the same time. c. are phenotypically indistinguishable. d. can mate and produce fertile offspring e. pass the text of sympatry.

25. d. can mate and produce fertile offspring

26. The solidified remains or imprint of a previously existing organism is called a a. sediment. b. layer. c. fossil. d. mineral.

27. c. fossil.

28. Why are fossils evidence of evolution? A. They show that living organisms have remained unchanged throughout time B. They provide a history of life on earth C. They show what types of DNA organisms had D. They show that organisms have adapted to extreme environments

29. B. They provide a history of life on earth

30. Fossils of animals the size of goats were dated at 5 million years old. Similarly, fossils of larger animals were dated at 3 million years old. Both animals were similar in body structure to today's horses. Using these data, which inference can scientists make? A. The animals were probably ancestors of today’s horses B. The animals had no relationship to one another. C. Today's horses and these animals probably lived together at some time in the past. D. Today's horses are faster than these animals were.

31. A. The animals were probably ancestors of today’s horses

32. One very important mechanism for evolution is genetic drift, which is the a)Random change in genes within a population b)Formation of new species c)Evolution of two species in response to each other d)Ability of an organism to survive in its environment

33. a)Random change in genes within a population

34. Fossils are useful in a)Determining how species have change over time b)Determining the absolute age of rock layers only c)Explaining the theory of natural selection d)Supporting the theory that mutations are not always negative.

35. a)Determining how species have change over time