Difference between Algae and Fungi (Table) | easybiologyclass
The tiny lichen is a critical part of the food chain, but how do algae and fungi work together to form these symbiotic organisms?. Algae vs Fungi: A Comparison Table of Similarities and Difference between Ø Symbiotic members are present in both groups (algae with animals, fungi with in algae, Clamp connection and crozier formation are present in higher fungi for. Discusses parasitic and mutualistic relationships of fungi. involving fungi are mycorrhiza (fungi and plant roots) and lichen (fungi and either cyanobacteria or green algae). Compare and contrast mycorrhiza and lichen.
Lichens : Symbiotic Relation Between Algae and Fungi
What is not as clear is whether most obligate species-level symbiotic relationships, such as seen in lichens and corals, also have measureable levels of codivergence. Typically, these diffuse symbiotic and mutualistic interactions are complicated by variation in partner identity or where more than one symbiotic partner is involved, such as vascular plants and their root-inhabiting mutualists Hollants et al.
Further, it is much less clear that the causal processes involved in these coevolving symbiotic relationships will produce a pattern of codivergence given the increased opportunity for host switching. Lichens are a classic example of a mutualistic symbiosis. Lichen thalli are the result of an association between a fungus the mycobiont and a photobiont, which is usually a green alga, but may also be a cyanobacterium Nash, In all lichens, the photobiont provides photosynthate to the mycobiont, which in turn provides habitat, water and nutrients to the photobiont Honegger, ; Nash, The symbionts of lichens are relatively poorly known because they are very often difficult to culture and identify, particularly many of the photobiont partners Ahmadjian, ; del Campo et al.
However, in the last two decades a great deal of molecular work has been done to address this, showing variable patterns in partner identity and other patterns of association DePriest, This variable, and seemingly diffuse, mutualism provides a complex model system for addressing questions regarding the role of evolutionary processes in forming and driving ecological patterns in species interactions and how this affects community structure. The first step in understanding how a mutualistic symbiosis might affect community structure is to determine whether or not there is specificity in the symbiosis.
For example, Widmer et al. Thus, it appears that there is variability in association patterns among different lichen taxa Fahselt, Several mechanisms are proposed to underpin the patterns in phylogenetic congruence observed for lichens. If symbiont co-dispersal is coupled with genetic drift, a pattern of co-diversification is likely to emerge. Further, most green algal photobionts commonly occur in a free-living state, although for some taxa, such as Trebouxia, much about their life cycles and availability in the environment is unknown Sanders, Peltigera canina, the dog lichen is used as medicine for hydrophobia in ancient days.
Lobaria pulmonaria, lungwort are used for the diseases of lungs respiratory diseases and T. Parmelia is useful against epilepsy. Usnea species are good against urinary diseases. Xanthoria sp is used in jaundice etc Some lichens possess anticarcinogenic properties.
The lungwort lichen is used in tanning, in perfumery. The cell walls of the fungi of certain lichens contain colouring matters. Species of Rocella and Lecanora yield a most important colouring matter known as Orchil or Cudbear. This is used in colouring woolen and silk fabrics.
It is also used for manufacturing litmus papers which are used in laboratories for acid and base identification. It is obtained from Roccella montagnei. In Russia and Sweden, lichens are used for the production of alcohol. Some lichens are harmful to industrial products because they cause considerable damage to glass surfaces and marble stones due to etching. Ecological Importance of Lichens: Lichens Contribute to Soil Formation: Lichens thrive in undisturbed sites where nothing else will grow.
They grow on rocks, barren soil and the bark of dead or live trees. They are not parasitic when they grow on trees, they just use the tree bark as a home. They enrich the soil by trapping water, dust, and silt. When lichens die they contribute organic matter to the soil, improving the soil so that other plants can grow there. Lichens producing apothecia are discussed further in the section dealing with lichen-forming discomycetes. In the case of L.
Although appearing whitish, the margin contains green algae, the photobiont, and will be seen to be green if cut lengthwise. Some lichens produce their asci in perithecia such as those in the photograph of Hydropunctaria maura at right. Perithecia are flask-shaped structures that open to the outside by a pore called an ostiole.
Lichens producing apothecia are discussed further in the section dealing with lichen-forming pyrenomycetes. The ostioles in both perithecia at right can be seen as small circular areas at their tops. There are some other ways that asci can be produced by lichens, but perithecia and apothecia are by far the most common. The photographs above illustrate two other types you may encounter. The first are structures called lyrellae. These are similar to apothecia but are greatly elongated.
In the case of Graphis scripta, shown in the photo, the lyrellae are highly branched and may resemble some kind of mysterious writing.
MUTUALISMS BETWEEN FUNGI AND ALGAE
The second photograph, of Calicium trabinellum, illustrates a mazaedium, a kind of stalked apothecium in which the asci dissolve and leave the ascospores to pile up in a powdery mass. A few basidiomycetes are also capable of forming lichens. These are not generally considered to be highly-developed relationships yet there is no doubt they function as lichens.
The first of the two photos above shows Multiclavula mucida. In this species the basidia and basidiospores line the surface of the upright "fingers" and under cool moist conditions release the spores to drift in the wind. The photobiont, a green alga, forms a thick crust of the the substrate, in this case rotten wood.
The algae are enclosed by the hyphae of the mycobiont. In the second picture the mycobiont is Lichenomphalia umbellifera, a mushroom. The photobiont and its relationship with the phytobiont are the same as in M. Since these sexual structures reproduce only the fungus, the resulting spores must be fortunate enough to land on an appropriate alga, or perish.
However, there is another way. If the lichen can disperse propagules containing both myco- and photobionts then it will be able to develop in any suitable habitat. However, this type of reproduction is strictly clonal and does not allow for the kind of genetic recombination that occurs during sexual reproduction.
Fungi Symbiosis ( Read ) | Biology | CK Foundation
Clonal reproduction of lichens can occur in several ways. The simplest of these is simply to separate a piece of the thallus containing both alga and fungus and send it off by wind or water to develop in a new place.
This kind of reproduction is common among lichens and generally effective. There are more highly developed forms of clonal reproduction, two of which are represented in the photographs above. In the first the lichen has produced soredia. Soredia are small bundles of algae held together by fungal hyphae.
They are small enough to be carried by wind yet guarantee the presence of both partners. The illustration above left shows a young thallus of the foliose lichen Peltigera didactyla. In this species the upper surface becomes dotted with soralia, special structures for the production of soredia.
In the photograph, the soralia have released granular masses of soredia. The other photograph above is a highly magnified view of isidia, small coral-like branches containing both mutualists that can break off and drift to a new habitat.
The lichen in the picture is Xanthoparmelia conspersa, a common lichen on exposed rock in New Brunswick. Lichen habitats One of the fascinating aspects of lichen biology is the ability of these organisms to occupy habitats that would be totally in inhospitable to other organisms.