Animal cells have many distinct characteristics when compared to plant cells, including their varied shapes, their many types of organelles, their centrioles, cilia and lysosomes, and their cell-to-cell junctions. Animal cells also lack chloroplasts and cell walls, which are found in plant cells.
The varying and irregular shapes of animal cells are a distinct characteristic, while plant cells have regular, rectangular shapes. This is due mostly to the rigidity of the cell wall that animal cells lack.
Another characteristic of animal cells is the many types of organelles. Among these structures and organelles are the cell membrane, centrioles, cytoplasm, endoplasmic reticulum, golgi complex, lysosomes, microtubules, mitochondria, nucleus, nucleollus, nucleopore, ribosomes, cytoskeleton, cilia, flagella and peroxisomes.
Centrioles, only found in animal cells, are necessary during cell division. They organize the microtubules. Cilia are also characteristic to animal cells. They are protrusions attached to the cell that help the cell to move. Finally, lysosomes are also found exclusively in animal cells. These are enzymes that are necessary during the digestion of nucleic acids.
Finally, animal cells are characterized by their cell-to-cell junctions. These junctions come in three types. Tight junctions form seals between tissues, adhering junctions enable tissues to stretch and gap junctions form channels.