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    Ok, I just want to confirm a few things that im not too sure about in Biology.

    1. In Photosynthesis you have photosystem I P700nm and photosystem II P680nm. Are the "primary pigment" that exist in these two photosystems classified as Chlorophyll a each absorbing a different wavelength of light?

    2. Ok we produce reduced NADP at the end of light dependent stages. Is the equation:
    NADP+ + 2H+ + 2e- = reduced NADP

    OR

    NADP+ + H+ + 2e- = reduced NADP

    ?

    3. Do all channel proteins only open when there is ATP for energy available or can some channel proteins just be open permanently anyway?

    4. Reabsorption of substances into the blood occurs in the proximal convuluted tubule P.C.T. (of the kidney). Sodium ions are initially actively pumped into the blood from the PCT cell wall cells. Sodium from the filtrate (in the lumen of the PCT) is then allowed to move into the cells of the PCT cell wall, and cotransport glucose and amino acids. How do sodium ions from the filtrate pass through? What do glucose and amino acids pass through to be "co-transported" into these cells? I think the answer to this is protein channels, but if so, do they pass through THE SAME PROTEIN CHANNEL AT THE SAME TIME?

    All these questions are seemingly are un-answered by my textbooks, so I hope ppl on this forum can help Thanks

    (Original post by ResidentEvil)
    3. Do all channel proteins only open when there is ATP for energy available or can some channel proteins just be open permanently anyway?

    I think some are open anyway. In general passive transport (which can be diffusion through protein channels) does not require ATP

    4. Reabsorption of substances into the blood occurs in the proximal convuluted tubule P.C.T. (of the kidney). Sodium ions are initially actively pumped into the blood from the PCT cell wall cells. Sodium from the filtrate (in the lumen of the PCT) is then allowed to move into the cells of the PCT cell wall, and cotransport glucose and amino acids. How do sodium ions from the filtrate pass through? What do glucose and amino acids pass through to be "co-transported" into these cells? I think the answer to this is protein channels, but if so, do they pass through THE SAME PROTEIN CHANNEL AT THE SAME TIME?

    All these questions are seemingly are un-answered by my textbooks, so I hope ppl on this forum can help Thanks
    I think for this one there is a kind of special protein channel that moves 2 things at the same time. It's a bit hard to explain without pictures, but if you look up the sodium-potassium pump there might be a pic in your book, as this is another example of co-transportation.
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    (Original post by ResidentEvil)
    Ok, I just want to confirm a few things that im not too sure about in Biology.

    1. In Photosynthesis you have photosystem I P700nm and photosystem II P680nm. Are the "primary pigment" that exist in these two photosystems classified as Chlorophyll a each absorbing a different wavelength of light?

    2. Ok we produce reduced NADP at the end of light dependent stages. Is the equation:
    NADP+ + 2H+ + 2e- = reduced NADP

    OR

    NADP+ + H+ + 2e- = reduced NADP

    ?

    3. Do all channel proteins only open when there is ATP for energy available or can some channel proteins just be open permanently anyway?

    4. Reabsorption of substances into the blood occurs in the proximal convuluted tubule P.C.T. (of the kidney). Sodium ions are initially actively pumped into the blood from the PCT cell wall cells. Sodium from the filtrate (in the lumen of the PCT) is then allowed to move into the cells of the PCT cell wall, and cotransport glucose and amino acids. How do sodium ions from the filtrate pass through? What do glucose and amino acids pass through to be "co-transported" into these cells? I think the answer to this is protein channels, but if so, do they pass through THE SAME PROTEIN CHANNEL AT THE SAME TIME?

    All these questions are seemingly are un-answered by my textbooks, so I hope ppl on this forum can help Thanks
    1) Both are chlorophyll a, with different absorption peaks.
    2) NADP+ + 2H+ + 2e- ----> NADPH + H+
    3) Some channel proteins are passive (i.e. those involved in facilitated diffusion).
    4) It is via a cotransport mechanism, or a symport, in this case.
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    (Original post by ResidentEvil)
    Ok, I just want to confirm a few things that im not too sure about in Biology.

    1. In Photosynthesis you have photosystem I P700nm and photosystem II P680nm. Are the "primary pigment" that exist in these two photosystems classified as Chlorophyll a each absorbing a different wavelength of light?

    4. Reabsorption of substances into the blood occurs in the proximal convuluted tubule P.C.T. (of the kidney). Sodium ions are initially actively pumped into the blood from the PCT cell wall cells. Sodium from the filtrate (in the lumen of the PCT) is then allowed to move into the cells of the PCT cell wall, and cotransport glucose and amino acids. How do sodium ions from the filtrate pass through? What do glucose and amino acids pass through to be "co-transported" into these cells? I think the answer to this is protein channels, but if so, do they pass through THE SAME PROTEIN CHANNEL AT THE SAME TIME?
    1) yup, the 700 amd 680 refer to the wavelength of light i think.

    2 and 3 not sure

    4) the glucose and amino acids hitch a lift with the sodium as it were, so they do pass through the same channel simultaneously.
 
 
 
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