Fungi do not contains chlorophyll and thus are unable to photosynthesise and produce their own food while on the other hand plants contain chlorophyll and they photosynthesise to produce food.
Fungi are either parasites or decomposers and depend on others for their food.
Fungi differ from plants and they have their own kingdom due to the many reasons. Plants produce their own food by the process of photosynthesis while fungi do not take part in photosynthesis. They are heterotrophs, meaning they depend on other organisms for the supply of food. While plants are autotrophs. They make their own food with the help of sunlight and water.
Another reason for Fungi which differs from the plant are that Fungi do not have chlorophyll while plants have. The plant's cell wall is made up of cellulose while fungi have a cell wall made up of a protein called chitin. They do not reproduce by seeds. fungi also reproduce asexually by nature, for example by budding in yeast or spore production in mushrooms.
