In the Regulation of Glutamine Synthetase Activity, an Important Regulatory $\alpha$

question 8

Multiple Choice

In the regulation of glutamine synthetase activity, an important regulatory protein, P_II exists in two states, one with UMP covalently bound (P_II-UMP) , the other without (P_II) . Which of the following statements regarding $\alpha$ -ketoglutarate and P_II is correct?

• A)\(\alpha\)-ketoglutarate binds to P_II causing inhibition of adenylyltransferase
• B)\(\alpha\)-ketoglutarate binds to P_II causing activation of adenylyltransferase
• C)\(\alpha\)-ketoglutarate binds to P_II-UMP causing inhibition of adenylyltransferase
• D)\(\alpha\)-ketoglutarate binds to P_II-UMP causing activation of adenylyltransferase
• E)\(\alpha\)-ketoglutarate does not bind to either form of P_II

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Definitions:

Control Circuit

An electrical circuit designed to control the operation of devices in a system, often through the use of relays, switches, and timers.

Momentary

Describes a brief, transient action, especially in the context of switches or signals, where the effect lasts only as long as the actuating force is applied.

Holding Contacts

Contacts within a relay or starter that maintain the circuit's state even after the actuating force is removed.