simple biology definition question from destroyer # 4

Discussion in 'DAT Discussions' started by wkawk2416, Jun 13, 2008.

  1. wkawk2416

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    question: which is true about thylakoids

    answer : a series of disks stacked on each other that contain pigments needed for photosynthesis.

    I thought this was granum and not thylakoids.

    is it because the question is asking which is true about thylakoidS (plurals)? or i am just plain stupid.
     
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  3. osimsDDS

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    I could see how this could be tricky, but here...granum is the whole stack of thylakoids located in the stroma of chloroplasts...now the answer says they contain pigments for photosynthesis which you know thylakoids do because they contain on their membranes chloraphyll a, P700 photosystem I, p680 phhotosystem II...so yea it would be that one

    but i see wut your saying, the whole stack is whats throwing you off
     
  4. DCRedskinsRule

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    I must be confused. I thought thylakoids WERE membranes...just like folds membranes in stacks called grana. :confused:
     
  5. wkawk2416

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    i still don't get this question.

    logically the answer should be what DR romano says which is B

    but this question can throw me off easily. just to help me and some other people i got definitions off from wikipedia

    hope this helps

    thylakoid : A Thylakoid is a membrane-bound compartment inside chloroplasts and cyanobacteria. They are the site of the light-dependent reactions of photosynthesis. The word "thylakoid" is derived from the Greek thylakos, meaning "sac". Thylakoids consists of a thylakoid membrane surrounding a thylakoid lumen. Chloroplast thylakoids frequently form stacks of disks referred to as "grana" (singular: granum). "Grana" is Latin for "stacks of coins". Grana are connected by intergrana or stroma thylakoids, which join granum stacks together as a single functional compartment.

    granum : A thylakoid stack (granum, pl. grana) inside chloroplasts. A granum (plural grana) is a stack of thylakoid discs. Chloroplasts can have from 10 to 100 grana. Grana are connected by stroma thylakoids, also called intergrana thylakoids or lamellae. Grana thylakoids and stroma thylakoids can be distinguished by their different protein composition.
     
  6. osimsDDS

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    isnt the grana, a stack of thylakoids?? i think every disc is a thylakoid and many of those make up the grana no?
     
  7. Sea of ASH

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    osimsDDS ur the thylakoids is the individual sacks and the granum (pl. grana) is the stack of the thylakoids.
     

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