Why do plants have more in common at the cellular level with animals than bacteria?

Because plants, like animals, are multicellular and eukaryotic, while bacteria are unicellular and prokaryotic.

Explanation:

Plants are multicellular and eukaryotic beings. In these respects they are similar to animals and many types of fungi; however, they are different from bacteria at the cellular level, because the bacteria are prokaryotic and unicellular.

In addition, plants and animals share many cell structures in common, bacteria and plants share very few cell structures because of the different nature of their cells.

In short, plants are more similar to animals than bacteria when compared at the cellular level, because plants, like animals, are multicellular and eukaryotic.