The plant cell cytoplasm is surrounded by both cell wall and cell membrane. The specificty of transport of transport of substances is mostly across the cell membrane, because

Explanation

The transport takes place by the cell membrane because cell membrane is semi-permeable and composed of liquids that are arranged in bilayer structure along with proteins and carhydrate.
The lipid soluble molecules pass readily across lipid bilayer of cell membrane whereas novement of other molecules of small size is facilitated by porins, pores made up of proteins. while cell wall does not helps in transport of substances because it.
Cell wall is basically a non-living rigid structure forming outer covering over plasma membrane and it provides shape, mechanical strength and protection of the plant cell from damages and infection.