Basic Biology

Exercise #18 LAB REPORT Name: Kevin Scheive Section #:18 The Wolf, The Moose, and the Fir Tree Procedure 18.1 The Wolf, The Moose, and the Fir Tree Case Study – by Gary M. Fortier Part I Questions 1. What type of correlation (positive or negative) would you expect to see between the population densities or growth rates of each trophic level in this system (fir/moose/wolves) under the primary productivity hypothesis? There is a positive correlation, because if trees increase then moose increase as well because there’s more energy available for the moose, if the moose population increases then the population of wolves increase because the wolves have more to eat now. 2. What type of correlations would you predict under the trophic cascade hypothesis? In the trophic cascade hypothesis, there is an opposite correlation between the wolves and the fir trees and the same correlation between the wolves and the moose. 3. What would you predict as the effect of wolf removal on plant growth under each hypothesis? Under the trophic cascade hypothesis, plant growth would decrease as a result in the increase of the moose population. According to the primary productive hypothesis, however, there would be no change. 4. What assumptions are made regarding the measurement of growth rates in balsam fir? Regarding the long-term impact of moose herbivory on balsam fir? Do these assumptions seem warranted? It is assumed that the balsam fir has a constant rate of growth. Moose herbivory impacts the balsam fir as it is a secondary source of food during the summer but during the winter it is the easiest to obtain, and these assumptions do not seem warranted. 1 Exercise #18 Part II Questions 1. What is the purpose of each figure? Are there unclear terms or confusing aspects to any figure? It shows the relationships and population changes of organisms. 2. How do the maxima and minima of the ring-width indices correspond to changes in moose density? The ring width in the west has an inverse correlation to the moose population which means that there are more moose in the west to eat the fir trees. The ring width in the east is directly correlated to the moose population which means that there are less moose in the east side of the island. 3. Does this support the primary productivity hypothesis, the trophic cascade hypothesis, or neither? This supports the trophic cascade hypothesis, because of the inverse correlation of the populations. 4. Do firs from either end of the island (east/west) respond the same way to changes in moose density? How can you account for any observed differences? No, because the west is inversely correlated and decreases when moose population increases and when moose population increases the ring width in the east increases as well. 5. How do the maxima and minima of the wolves correspond to changes in moose density? How might you account for this relationship? The correlation between moose and wolf population is inversely proportional. It might be because when there are many wolves they eat a lot of moose so the population decreases. 6. Which hypothesis is supported by the data on annual AET? The AET rate changes with temperature and rainfall, and it supports the primary productivity hypothesis because AET is the rate that the trees grow and it is directly correlated with the ring width of the trees. The ring width then results in the changes in the population of wolves and moose. Part III Questions 1. Are there any confusing aspects to the figures or caption above? It is very confusing to follow all the seemingly random and close lines on the graph. 2

BIO | 10 | Basic Biology | lab | Exercise #18 LAB REPORT Name: 

lab_17.docx-Exercise #17 LAB REPORT Name: Kevin

Chapter 1 Quiz 1. Why are correlations less convincing than controlled experimental results? Correlations do not eliminate as many alternative hypothesis 2. Which of the following is a testable hypothesis? Avoiding contact with other people reduces the chance of catching a cold 3. Which of the following is a true statement about experimentation? Some hypothesis cannot be tested by experimentation 4. What would be the most trustworthy source of scientific information? Peer-reviewed research publications 5. Which statement makes a prediction for the hypothesis “bird species have decreased in number in a particular wetland due to construction traffic”? If a wetland area is disrupted by construction vehicles, then the number of bird species will decrease. 6. When graphing data, what scientific information do scientists plot on the x-axis? Independent variable 7. Which feature is necessary for a scientific hypothesis? It is falsifiable 8. Why are hypothesis never accepted as proven by scientists? Alternative hypothesis might provide a better answer to the research question 9. What is the result when a well-tested hypothesis is supported by many independent studies in the scientific community? The hypothesis would be considered a scientific theory 10. What is the purpose of double-blind experiments? To minimize the effects of human basis on the results. 11. When an experiment has a large sample size, and there is a large difference between the results in the experimental and control groups, how likely is that the experimental results are statistically significant? Very likely 12. Which group would be the most effective control subjects in a test of an experimental treatment? The control group should have characteristics very similar to the experimental subjects 13. Which of the following statements is an example of anecdotal evidence? Dr. Jackson’s informercial statement “I believe my personal cure for bowel disorders is more effective than any drug I’ve ever prescribed in 20 years of practicing medicine.” 14. When would an experimental result be considered statistically significant? The result is unlikely to be due to chance alone 15. What would a news report on CNN that describes recently published on a new treatment for cold be an example of? Secondary source 16. Why is the scientific method used? To answer specific questions about the natural world 17. Why is the random assignment of individuals to experimental and control groups important for an experiment? It ensures that each group will better represent the population as a whole 18. There is a strong correlation between stress and susceptibility to colds. What does this mean?

BIO | 10 | Basic Biology | assessment | Chapter 1 Quiz 1. Why are corr

Quiz_for_bio_10_.docx.docx-Chapter 4 quiz 1) If necessary,

Chapter 2 Quiz 1. Which of the following is an element? Hydrogen 2. Which organelle performs cellular respiration? Mitochondrion 3. What kind of bond holds two water molecules to each other? Hydrogen bonds 4. If life on Mars is fundamentally like life on Earth, its macromolecules will be based on which element? Carbon 5. Because the electrons in a water molecule are shared unequally between hydrogen and oxygen, water is said to be? Polar 6. Which of the following are found in the nucleus of an atom? Neutrons and protons 7. Proteins are polymers of Amino acids 8. Nonliving things include fire, water, and viruses. Many features of living things are also found in nonliving things. Of the following features, which is most likely to be absent in nonliving things? Homeostasis 9. The plasma membrane of a photosynthetic eukaryotic cell… Isolates the cell’s contents from the external environment 10. Each of the following is a feature of all known living things EXPECT. Genes made from proteins 11. What kind of molecule forms a bilayer that is the basis for all cellular membranes? Phospholipid 12. An atom will be least likely to form chemical bond with other atoms when The valence shell is full of electrons 13. A solution with a pH of 2 has an H+ ion characteristic that is ____ than a solution with a pH of 4. 100 times higher 14. Sodium chloride is composed or molecules that are stable when dry. In the presence of water, however, the atoms that compose the molecules separate from each other. What type of chemical bond holds the dry substance together? Ionic bonds 15. According to the theory of evolution, which states that all life-forms on Earth from a common ancestor, all living organisms Share a common organic chemistry 16. What kind of bond holds the atoms of a single water molecule together? Covalent bonds that are polar 17. Imagine a newly discovered biological molecule that is mostly hydrophobic in its structure. This new molecule will most likely be classified as a Lipid 18. Which features is found in both prokaryotic and eukaryotic cells? DNA 19. Which of the following pairs of molecules can be held together by a hydrogen bond? Two polar molecules

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