A discuss the role of green plants in transforming

Info icon This preview shows pages 3–4. Sign up to view the full content.

View Full Document Right Arrow Icon
(a) Discuss the role of green plants in transforming the Sun’s energy into a form that can be used by heterotrophs. (b) Discuss the flow of energy from producers through top carnivores in a food web in terms of the laws of thermodynamics. 2005:
Image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
AP BIOLOGY 4 A controlled experiment was conducted to analyze the effects of darkness and boiling on the photosynthetic rate of incubated chloroplast suspensions. The dye reduction technique was used. Each chloroplast suspension was mixed with DPIP, an electron acceptor that changes from blue to clear when it is reduced. Each sample was placed individually in a spectrophotometer and the percent transmittance was recorded. The tree samples used were prepared as follows. *Sample 1 – chloroplast suspension + DPIP *Sample 2 – chloroplast suspension surrounded by foil wrap to provide a dark environment + DPIP *Sample 3 – chloroplast suspension that has been boiled + DPIP Percent Transmittance in Three Samples Time (min) Light, Unboiled % Transmittance Sample 1 Dark, Unboiled % Transmittance Sample 2 Light, Boiled % Transmittance Sample 3 0 28.8 29.2 28.8 5 48.7 30.1 29.2 10 57.8 31.2 29.4 15 62.5 32.4 28.7 20 66.7 31.8 28.5 (a) On the axis provided, construct and label a graph showing the results for the three samples. (b) Identify and explain the control or controls for this experiment. (c) The differences in the curves of the graphed data indicate that there were differences in the number of electrons produced in the three samples during the experiment. Discuss how electrons are generated in photosynthesis and why the three samples gave different transmittance results. 2006 In many ways, all organisms in a food web can be said to be solar-powered. The producer level of the food web is responsible for the transformation of the solar energy into a form that can be used by other living organisms. (a) Discuss the role of green plants in transforming the Sun’s energy into a form that can ultimately be used by heterotrophs. (b) Discuss the flow of energy from producers to top carnivores in a food web in terms of the laws of thermodynamics. 2009: Water is essential to all living things. (a) Discuss THREE properties of water (b) Explain each of the following in terms of the properties of water. You are not limited to the three properties discussed in part (a): The role of water as a medium for the metabolic processes of cells The ability of water to moderate temperature within living organism and in organisms’ environments The movement of water from the roots to the leaves of plants 2010 Biological molecules can be separated by using chromatographic techniques. The diagram above shows the separation of several spinach leaf pigments by paper chromatography. Using the diagram above: (a) Explain how paper chromatography can be used to separate pigments based on their chemical and physical properties. (b) Discuss the role of pigments both in capturing light energy and in converting it to the chemical energy of ATP and NADPH. (c) Use the ruler above to determine the R f value of xanthophylls. Show your calculations.
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern