Cystic fibrosis is caused by a recessive lethal gene and can be detected by an excess concentration of chloride in sweat. A normal man whose sister has cystic fibrosis, his normal wife whose brother has cystic fibrosis. What is chance of cystic fibrosis in their child?

#Question id: 4627

#Unit 11. Evolution and Behavior

Which of the following is not one of Charles Darwin's observations?

#Question id: 4628

#Unit 11. Evolution and Behavior

Which group is composed entirely of individuals who maintained that species are fixed (i.e., unchanging)?

A) Linnaeus

B) Lyell

C) Darwin

D) Aristotle

E) Cuvier

#Question id: 4629

#Unit 11. Evolution and Behavior

In the mid-1900s, the Soviet geneticist Lysenko believed that his winter wheat plants, exposed to ever-colder temperatures, would eventually give rise to ever more cold-tolerant winter wheat. Lysenkoʹs attempts in this regard were most in agreement with the ideas of

#Question id: 4630

#Unit 11. Evolution and Behavior

Which pair would have been likely to agree that strata such as those depicted here were deposited gradually over long periods of time by subtle mechanisms that are still at work?

#Question id: 4631

#Unit 11. Evolution and Behavior

As a young biologist, Charles Darwin had expected the living plants of temperate South America would resemble those of temperate Europe, but he was surprised to find that they more closely resembled the plants of tropical South America. The biological explanation for this observation is most properly associated with the field of

#Question id: 4632

#Unit 11. Evolution and Behavior

Which of these conditions should completely prevent the occurrence of natural selection in a population over time?