A second experiment used the same chloroplasts with an artificial electron donor that bypasses PSII and feeds electrons directly to the plastoquinone pool. DCMU was again added.
Why does DCMU no longer block DCPIP reduction?
- A
DCMU is destroyed by the artificial donor.
- Bcheck_circle
The artificial donor injects electrons downstream of the DCMU block, restoring flow.
- C
DCPIP becomes light-independent.
- D
PSII regenerates spontaneously.
Explanation
Bypassing the PSII blockade with an alternate electron source allows electrons to reach DCPIP via the rest of the chain - confirming where DCMU acts within the ETC.