Explain why the cell membrane in animal cells is thicker than in plant cells.

Animal cells are unique in that they do not exhibit cell walls.Plant cells exhibit very stiff pecto-cellulosic walls, notably because of the presence of cellulose microfibrils, the stiffness of which compares to that of steel.

Ithink the answer is nuclear membrane

Air enters through the nose (and sometimes the mouth), moves through the nasal cavity, the  pharynx, the  larynx, enters the  trachea, moves through the  bronchi  andbronchioles  till the alveoli.