22. Which of the following situations has the greatest potential for observer bias in an experimental study?
A. Dr. Jones is evaluating cancer patients for their responses to a new therapeutic drug. She knows which patients are receiving the drug and which patients are receiving the placebo.
B. Graduate student Jonas Brown is conducting a survey of weight loss for his professor. He asks each student in the study the same questions.
C. Ms McCormack is an outside consultant who is conducting a health and wellness survey for a pharmaceutical company. She neither knows the name of the company, nor the name of the drug being tested during the survey.
D. Dr. Smith is analyzing biopsy examples from rats who have been given either a placebo or an experimental drug believed to reduce inflammation. Each sample is identified by a code number; therefore, Dr. Smith cannot tell which treatment each rat received.
E. Ms Williamson is a research technician who surveys the responses to a new cold remedy by a study group. She only knows the e-mail address of each participant and asks them identical questions by computer.

23. Changing one amino acid within a protein could change what about a protein?
A. The primary structure
B. The overall shape of the protein
C. The function of the protein
D. All of the above

24. A shortage of phosphorus in the soil would make especially difficult for a plant to manufacture
A. DNA
B. Protein
C. Cellulose
D. Fatty acid

25. A biochemist measures the amount of DNA in cells growing in the laboratory. The quantity of DNA in a cell would be found to double
A. Between prophase and anaphase of mitosis
B. Between the G1 and G2 phases of the cell cycle
C. During the M phase of the cell cycle
D. Between prophase I and prophase II of meiosis

26. Of the following, which describes protists most inclusively?
A. Multicellular eukaryotes
B. protozoans
C. eukaryotes that are not plants, fungi or animals
D. Single celled organisms closely related to bacteria
E. All of the above

27. Which of the following is not a function of mitosis in humans?
A. Repair of wounds
B. growth
C. production of gametes from diploid cells
D. replacement of lost or damaged cells

28. Sports physiologists at an Olympic training center want to monitor athletes to find at what point their muscles are functioning anaerobically. They can do this by monitoring the buildup of:
A. ADP
B. Lactic acid
C. Carbon dioxide
D. Oxygen
E. protein

29. You look into a light microscope and view an unknown cell. What might you see that would tell you whether the cell is prokaryotic or eukaryotic?
A. A rigid cell wall
B. A nucleus
C. A plasma membrane
D. Ribosomes

30. A sulfur atom has 6 electrons in its third (outermost) shell, which can hold 8 electrons. As a results it can form______ covalent bonds with other atoms.
A. 1
B. 2
C. 6
D. 8

ESSAY SECTION

Complete 8 essay questions: complete questions 1-6 (required) as well as complete 2 of questions 7-10.

REQUIRED QUESTIONS: 1-6 must be answered.

ALTERNATE QUESTIONS: 7-10. Select 2 of these questions to answer.

INSTRUCTIONS: Each question is worth 2.5 points. Total points for this section is 20 points.

**Do not enter your answers here.** Type your answers into the Answer Sheet provided by your instructor.

1. You scoop up a water sample from a local pond nearby, because you are curious about the possible microbes that might live there. After looking at several slides that held drops of the sample, you noticed two different kinds of cells: One kind was very small and had no separate internal structures; the other kind was much larger, and it contained several kinds of internal structures that were physically different from each other. Please name each cell and briefly describe their overall similarities and differences.

2. PKU (phenylketonuria) is an enzyme deficiency disease that only develops in individuals who are homozygous recessive for that gene. An individual with PKU has parents that do not have this disease. What is the parents' genotype for the gene responsible for PKU? What is the probability that they may have another child with PKU? How many future children of the affected individual will be carriers? Explain your answers.

3. Describe the major land biome where you live. How have human activities changed the landscape and how has this affected native species? Include specific examples.

4. Name 2 similarities between in the structure or function of chloroplasts and mitochondria. Name two differences.

5. Why is it difficult to draw a conclusion from an experiment that does not include a control group?

6. Humans share 99% of their genes with chimpanzees, 90% with mice, 50% with fruit flies, and 37% with celery. Please explain the evolutionary significance of these data.

7. The habitat of one species of tropical fish is red coral reefs. The large majority of the fish in this population are red. A few individual fish carry a mutation that prevents the production of the red pigment; as a result these individual fish are white. The temperature of the ocean where these fish live gets warmer and warmer over a 10 year period, and as a result the coral is bleached and turns white. Use what you have learned about natural selection to explain how this bleaching event may have affected the evolution this fish population (not including possible direct effects of warmer temperatures on the fish). Include the following terms in your explanation: differential reproduction, beneficial trait, allele frequency, selection pressure, evolution.

8. Use what you have learned about energy transfer in food chains and the second law of thermodynamics to explain why it is an environmentally good choice to eat a plant based diet. Include the following terms in your answer: producer, herbivore, omnivore, trophic level, resources and energy

9. You have read that inorganic fertilizers contribute to water pollution and would like to make a switch from inorganic fertilizers to organic compost in your vegetable garden. A friend graciously gives you a truck load of his compost. As a good researcher and critical thinker you are not convinced that organic compost will yield the same results as the inorganic fertilizer you have used for years with good results. To draw your own conclusion based on scientific evidence you decide to conduct an experiment in your garden. State a good hypothesis, design an experiment (include test subjects, sample size, control(s), dependent and independent variables, type of data collected) and hypothetical results/conclusion. Does your conclusion support the hypothesis?