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General characters:The intimate symbiotic association of fungi and algae is called lichens.Algae get protection and get moisture from fungus.Fungi get nutrition from the algae.The food substances diffuse from algae to fungi.The algae of lichens mostly belong to Chlorophyta and cyanobacteria. Distribution: Lichens have worldwide distribution. The form major part of vegetation in Polar Regions. They can withstand extreme temperatures. Classification: ...

General structure Physcia is foliose lichen. Physcia is divided into four regions internally. These regions are: 1. Upper cortex: It is present at the upper regions. It is composed of closely packed hyphae. Spaces are absent between them. if spaces are present, they are filled by gelatinous material. The upper surface may be smooth or it has hair like structures. ...

Scientific classification Division Bryophyta Class Hepaticae Order Marchantiales Family Ricciaceae Genus Riccia OCCURRENCE The genus Riccia has aboutI30 species. Some botanists have reported its 200 species. Many of its species are found in Punjab. Kashmir and Western Himalayas. The species are found scattered from hilly and plains areas. All the species are terrestrial. They grim on damp soil or moist ...

Occurrence Anthoceros grows on moist soil. They are present in shady places or ;n the crevices of rocks. Anthoceros erecrus, A. himalayensis, and A. chambensis are commonly found in Westeni Himalayas General structure Anthoceros has thallus body. It is lobed and it has irregular or dichotomous branches. The lobes have a wavy margin. Anthoceros form small rosette like plant. Unicellular ...

Occurrence It grows on moist rocks. It also occurs on shaded sides of tree trunks. It forms dense mats closely covering the substratum. Some are aquatic and grow in cool waters. General structure Plant body is gametophyte. It is composed of three parts: I.  Stem: The mature plant consists of a slender dorsoventral stem. it branches extensively. The prostrate stems ...

Occurrence Of Polytrichum  Polytrichum have worldwide distribution. They are very common in cool temperature and tropical regions. Plants live in cool and shady places. General structure of Polytrichum  The main plant body is gametophyte. The adult plant consists of two parts: rhizome and upright leafy shoot. 1.  Rhizome: It is horizontal portion and grows underground. It bears three rows of small brown ...

Funaria Occurrence Funaria is  terrestrial moss. It grows in the form of bright green velvety patches in shady and damp places. Genus Funaria is composed of 117 species. Funaria hygrometrica is most common and worldwide species. It grows well on burnt soil. It grows best in the presence of calcium, potassium, nitrogen and phosphorus. Vegetative structure of gametophyte Structure of ...

Fossil & Fossilization – importance , types and divisions PALEOBOTANY The study of fossils of plant life of the geologic past is called paleobotany. Paleobotany tells us the story of preserved vestiges of the plant life of the past. In simplified language paleobotany may be defined as a branch of botany which deals with the study of such plants which ...

Occurrence and evolution of Pteridophytes Pteridophyta is a group of ancient plants. They formed the dominant part of the earths during Palaeozoic and Mesozoic periods. Majority of Pteridophytes became extinct. They are preserved in the form of fossils or coal deposits. Only a few living Pteridophyta are left. General structure The vegetative plant body is a sporophyte in Pteridophytes. Sporophyte ...

PSILOPSIDA TYPE PSILOTUM Occurrence Psilotum is distributed in tropical and subtropical regions. It may grow as an epiphyte on the bark of trees. It also grows on soil where humus is abundantly available. General structure The plant body is sporophyte. The plant is a small shrub. The plant body is differentiated into rhizome and aerial branches. 1.  Rhizome: Rhizome is ...