All plants have a cell wall, all mammals have a cell membrane. a cell membrane is semi-permeable it allows mammal cells to absorb needed nutrients, oxygen and deposit waste into the blood stream where it is excreted through urine and feces. a plant cells nutrients are absorbed through the root system and leaves, waste is excreted in the form of oxygen through the plant itself.
ha incrementado la importancia de la ecología por los cambios que han ocurrido a través de el plante, en nuestra época más que nada se necesita proteger el planeta antes de que sea demasiado tarde.
