AP Biologymediummcq1 pt

Electron micrographs show cytoplasmic channels, lined by plasma membrane, passing straight through the walls between neighboring plant cells. What do these structures accomplish?

A.These plasmodesmata connect adjacent cytoplasms into a symplast for direct transport and signaling.
B.They seal wall gaps against water loss to the surrounding air.
C.They anchor chloroplasts at fixed spacing for uniform light capture.
D.They spin cellulose microfibrils during wall deposition.

Explanation

Core Concept

Water, sugars, amino acids, and selected RNAs or proteins pass directly between cells through them. That continuity coordinates tissue-level behavior, including the spread of defense signals after herbivore attack. Traffic bypasses crossing two membranes and a wall separately.

Correct Answer

AThese plasmodesmata connect adjacent cytoplasms into a symplast for direct transport and signaling.

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