Kingdom Fungi: Fungi include heterotrophic, eukaryotic and non-photosynthetic organisms.

(a) Some fungi are known parasites, such as Puccinia, Albugo and Ustilago, and derive nutrition from hosts.

(b) Some fungi such as Mucor, Rhizopus, Penicillium and Agaricus are decomposers, saprophytes or saprobionts, deriving their nourishment from the dead remains of plants and animals.

Fungi maybe unicellular (yeast) or filamentous. The body of a filamentous fungus is called a mycelium and it is composed of several thread-like structures called appendages. Cell wall of fungi is composed of chitin and cellulose. Chitin is a tough complex of sugar. They store food in the form of glycogen. Fungi also exist in symbiotic association with algae, known as lichens. Certain fungi form a symbiotic association with an algal partner. This symbiotic association of fungi and algae is called a lichen. The algal component of the lichen is known as phycobiont and the fungal component of the lichen is known as mycobiont.