Tag: botany

In biology that lives in dead wood, leaves, or sticks, or organic debris is called as lignicolous. Lichens which grow on wood are called lignicolous, e.g., Cephalium.

Graphis scripta is a crustose lichen in Graphidaceae family.

In lichens, a relationship occurs in which the fungus lives as a dominant organism and algae like a slave, the relationship is known as helotism. It is a form of symbiosis in which one species is forced to perform tasks for another, for their mutual benefit. 

A lichen is a composite organism that arises from algae or cyanobacteria (or both) living among filaments of a fungus in a symbiotic relationship. The combined life form has properties that are very different from the properties of its component organisms. The fungus benefits from the symbiotic relation because algae or cyanobacteria produce food by photosynthesis. The algae or cyanobacteria benefit by being protected from the environment by the filaments of the fungus, which also gather moisture and nutrients from the environment, and (usually) provide an anchor to it. 

Lichens reproduce vegetatively by soredia formation. It is the most common form of reproduction where small protuberances are formed on the thallus. They may have a definite pustule or appear as greyish dust. Many lichens reproduce asexually, either by vegetative reproduction or through dispersal of diaspores, which contain a few algal cells surrounded by fungal cells. 

Lichens exhibit the symbiotic association between algae and fungi. In this plant, algae is the photosynthetic partner involved in food preparation and the fungal partner increases the surface area for the absorption of water and minerals. Also, the fungal partner is involved in sexual reproduction with the help of reproductive structures called apothecia.