A family of “intrinsic proteins” named for this structure transports water and other small, uncharged molecules, like urea and hydrogen peroxide, across it. For 10 points each:
[10m] Name this structure, which contains the SV and FV channels. Proton pyrophosphatase and V-type ATPases help create a proton gradient across this structure.
ANSWER: tonoplast [accept tonoplast intrinsic proteins; accept, but DO NOT REVEAL, vacuolar membrane or the membrane of the central vacuole; prompt on, but DO NOT REVEAL, central vacuole; reject “cell membrane” or “plasma membrane”]
[10e] The tonoplast is the membrane surrounding this organelle. In plants, tonoplast transporters maintain a proton motive force that enables the storage of nutrients in a large, central one of these organelles.
ANSWER: central vacuole
[10h] This fungal toxin strongly activates the interaction between proton ATPases and 14-3-3 proteins in the plant plasma membrane, rapidly acidifying the cell wall. Unlike coronatine, this toxin’s action in guard cells causes stomata to permanently stay open.
ANSWER: fusicoccin [accept fusicoccin-A or FC-A]
<S, Biology>