Why three reasons fail of the …

Several Objections have been raised against this two Kingdom classification. They are as following:
1) First formed organisms were neither plants nor animals.
2) Fungi differ in the structure, physiology and reproductive details from plants.
3) At the lower level of organisations there are several instances where the distinction of plants and animals actually vanish. For example, Euglena has both holophytic and holozoic nutrition and saprobic nutrition (mixotrophic nutrition or mixed form of feeding). Sponges are branched, fixed and irregular in outline just like plants. It's relatives have both holophytic and holozoic nutrition. Unicellular algae like Chlamydomonas are motile, possess regular shape, definite growth and photosynthetic organelles.
4) Groups of Unicellular algae (euglenoids, diatoms and dinoflagellates) and protozoa show sufficient degree of resemblance.