A glutamine-dependent signaling cascade that initiates this process begins with de-uridylation of P-II and GlnK, culminating in the transcription of nif genes. For 10 points each:
[10m] Name this process. An enzyme central to this process uses 16 ATP molecules in tandem with molybdenum-iron or vanadium-iron cofactors to reduce its triply-bonded substrate.
ANSWER: nitrogen fixation [prompt on nitrogen assimilation; prompt on assimilation or fixation]
[10h] Low nitrogen triggers rhizobia to secrete signaling lipochitooligosaccharides (“lipo-kite-oh-oligo-saccharides”), which are factors named for stimulating and forming these structures. These structures are mutualistic interaction sites between plants and nitrogen-fixing bacteria.
ANSWER: nodules [prompt on nod factors or nodulation]
[10e] Nodules are affixed to these plant organs, which are responsible for uptake of inorganic nutrients and water from soil.
ANSWER: roots
<ASU A, Biology>