Certain group of cells are classified as Eukaryotic cells because they possess a membrane-bound nucleus that houses their genetic material (DNA) in addition to other cellular organnelles. Organisms with eukaryotic cells fall within three major groups viz: Plants, Fungi and Animal. These three distinct organisms, although all eukaryotic, have their own differences.
As stated in the question, plant cells and fungal cells share a unique structure that the animal cell does not possess. This unique structure is the CELL WALL. In addition to their cell membrane, plant and fungal cells have cell walls that is made up of cellulose and chitin respectively. The cell wall confers rigidity upon their cells. However, animal cells lack cell walls in their cells.
The liver is the largest internal organ, because it has many important functions such as making bile, collecting circulated blood, and processing chemicals.
