Question

Plant Bio

Please type

What goes on inside the cell to make auxin flow downward? Draw two stacked plant

cells located in the shoot and draw the auxin influx and efflux proteins at their proper

place on the membranes. In what direction does the auxin flow through the tissue due

to the placement of the auxin transport proteins?

Answer 1

Auxin shows polar movement. This characteristic is known as polar auxin transport (PAT). PAT is achieved by specific membrane carrier protein known as PINFORMED protein. PIN proteins are auxin efflux carriers. AUX proteins are auxin influx carriers. The orientation of PIN proteins in the cell membrane determines the flow of auxin. CUP-SHAPED COTYLEDON is NAC domain contain transcription factor that reorients PIN proteins by an unknown mechanism.

Unpolarized PIN proteins Polarized PIN protein:s PIN polarization Directional flow of auxin