MCAS Biology Ms. Chen Name:
Date:
Do Now 1/13/15
Directions: For each question, underline KEY words in the question. Explain why you picked your answer.
1. Scientists measured and recorded the average body size in a bird population over time. One year, a period of cold weather killed many of the birds. A few generations later, the scientists observed that the average body size in the population was larger than it had been before the cold weather. The scientists concluded that the population had evolved through natural selection. Which of the following would provide the best evidence to support the scientists’ conclusion? A. The size of the bird eggs also increased over time. B. The birds with the largest body size were the males. C. The frequency of alleles for body size changed in the bird population. D.
The number of birds in the population had decreased by 50% or more.
2. Suppose scientists observe a shift in the distribution of body colors in the beetle population over time. Which of the following observations best supports the conclusion that the population has evolved? A. The reproductive rate for individual beetles has increased. B. The size of the beetle population has increased significantly. C. The sequences of body color genes are different among the individual beetles. D. The frequencies of the alleles for body color in the beetle population have changed.
3. What is the genetic material in the chromosomes of an animal’s cells? A. DNA B. glucosamine C. RNA D. transcriptase
