Why do plants cell contain cell wall but animal cells does not? i need an easy explanation

Hi

Explanation:

A plant cell needs a cell wall because they need a rigid structure to grow up and out. In addition, a plant cell wall makes sure that the cell does not burst  as water flows in-- a concept called "internal turgor pressure". It helps to maintain the shape and osmolarity of the cells. Animal cells don't need to do that.  

Plant cell needs cell wall whereas animal cell do not because the plants need rigid structure so that they can grow up and out so that they get lots of sunlight for making their food.  Animal cells have flexible cell membranes. So animal cells can have various shapes, but plant cells cannot and they have to take the shape of their cell walls.

i'm thinking (a) to keep sand in place; ////////////

explanation: a sand fence or sandbreak, like a snow fence, is used to force windblown, drifting sand to accumulate in a desired place. sand fences are employed to control erosion, sand dune stabilization, keep sand off roadways, and to recruit new material in desert areas.

voluntary muscles are controlled by the cerebellum.