AP BIOLOGY

Detailed explanation-1: -The apoplast pathway comprises of non living components of a plant body i.e., intercellular spaces and cell wall. The movement through apoplast is unregulated and fast. Symplast comprises of living components i.e., protoplasm, cell membrane and plasmodesmata.

Detailed explanation-2: -The apoplast comprises the intercellular space, the cell walls, and the xylem.

Detailed explanation-3: -Solution: Cytoplasmic streaming does not aid in apoplastic movement.

Detailed explanation-4: -Apoplast was previously defined as “everything but the symplast, consisting of cell walls and spaces between cells in which water and solutes can move freely". However, since solutes can neither freely move through the air spaces between plant cells nor through the cuticle, this definition has been changed.

Detailed explanation-5: -The symplast, in contrast, consists of the entire cytosol of all living plant cells and the plasmodesmata-which are the cytoplasmic channels interconnecting the cells. There are several potential pathways for molecules to move through the plant tissues: The apoplastic, symplastic, or transmembrane pathways.