Cell membrane

(a)  

Cell wall

(a)  

Concentration gradient

(a)  

Diffusion

(a)  

Endocytosis

(a)  

Exocytosis

(a)  

Facilitated diffusion

(a)  

Protein pump

(a)  

Membrane protein

(a)  

Osmosis

(a)  

Passive Transport

(a)  

Permeability

(a)  

Semi/selectively-permeable membrane

(a)  

Vesicle

(a)