Plants and animals are both multicellular eukaryotes. Along with fungi, they are the only organisms in the world that are capable of building large bodies. Unlike most fungi, plants and animals have differentiated tissues that develop into discrete organs.
On a cellular level, plants and animals are very similar. Both have cells that are large, compared to prokaryotic cells, and internally complex. All eukaryotic cells have simple plasma membranes, unlike the complex cell walls of prokaryotes. They also have complex internal arrangements of intracellular organelles that are specialized to perform various functions in the body's chemistry. Most plant and animal cells have a nucleus, which houses the organism's genetic material.
This genetic material is organized in a similar way for both groups. In each, DNA is arranged in a linear fashion, with identifiable chromosomes laid out along its length. This pattern of multiple chromosomes in a straight line is unique to eukaryotes, as prokaryotic organisms organize their DNA into a single ring-shaped chromosome.
Animals and plants differ in their means of acquiring food, with plants autotrophically synthesizing carbohydrates from sunlight and animals harvesting those nutrients by eating plants. However, the process of chemical digestion and energy transfer within cells is nearly identical.