You are working on a research project that involves a mutational analysis of the light harvesting complex Lhca1, which is an important light harvesting complex found in plants. Your labmate asks where this complex is located. You say it is in the.

Question

A.  outer chloroplast membrane
B.  inner chloroplast membrane
C.  thylakoid membrane
D.  stroma
E.  matrix

Clarify Question
What is the key concept addressed by the question?
What type of thinking is required?

  Gather Content
What do you already know about how light harvesting occurs in photo systems during photosynthesis? What other information is related to the question?

  Choose Answer
Do you have all the information needed to provide an explanation?

  Reflect on Process
Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?

Answer 1

C.  thylakoid membrane

Clarify Question
What is the key concept addressed by the question?
        · The question asks you to determine where the light harvesting complex Lhca1 is located so you can communicate this to your lab mate who is performing a mutational analysis.
What type of thinking is required?
        · You are being asked to take what you know about photo systems and light harvesting complexes and use, or apply, your knowledge to answer your labmate’s question.

  Gather Content
What do you already know about how light harvesting occurs in photo systems during photosynthesis? What other information is related to the question?
        · Photosynthesis is comprised of the light reactions, which produce ATP, NADPH, and oxygen and the Calvin cycle, which uses products from the light reactions to construct organic molecules from inorganic carbon dioxide. The light reactions capture and concentrate solar energy chlorophyll molecules clustered into light harvesting complexes like Lhca1. Can you recall where the light reactions and the Calvin cycle take place within chloroplasts?

  Choose Answer
Do you have all the information needed to provide an explanation?
        · Hopefully by now it should be clearer where particular photosynthetic processes take place within chloroplasts. During the light reactions, chlorophyll molecules arranged in a cluster, or light harvesting complex, absorb photons from the sun and elevate the potential energy of an electron stripped from a water molecule. The light reactions take place in the thylakoid membrane, which is the location of the photosystems and therefore complex Lhca1. The other answers can be eliminated because neither the outer nor the inner chloroplast membranes contain light harvesting molecules, and the stroma is where the Calvin cycle takes place, not the light reactions.

  Reflect on Process
Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?
        · Answering this question correctly depended on your ability to apply what you know about the light reactions, photo systems, and light harvesting clusters of pigment molecules like Lhca1 to provide an explanation to your labmate.
        · If you got a correct answer, nice job! If you got an incorrect answer, did you recall that the light reactions in photosynthesis rely on photo systems? Did you remember that photo systems contain reaction centers? Did you remember that the light reactions occur in the thylakoid membrane, and therefore the light harvesting complex Lhca1 must be located there as well?