Quiz_Lichens 1. Which of the following lichens is harmful? Usnea Umbellicaria Cetraria Labaria Explanation:Labaria is a type of lichen that can be harmful due to its production of toxic compounds. These compounds can be detrimental to other organisms in the environment. 2. Which of the following would appear as the pioneer organism on bare rocks : Liverworts Lichens Green algae Mosses Explanation:Lichens are often the first organisms to colonize bare rocks, initiating the process of ecological succession. Their ability to withstand harsh conditions and break down rocks into soil makes them pioneers in these environments. 3. Common phycobiont in a lichen is : Trebouxia Microsystis Cetrarea Euglena Explanation:Trebouxia is a common genus of green algae that forms symbiotic relationships with fungi in lichens. It is one of the most widespread phycobionts in lichen symbiosis. 4. A lichen having a branching form and growing either prostrate or erect on the ground is called : Foliose Crustose Fruticose Thallose Explanation:Fruticose lichens have a bushy or shrubby appearance and can grow either prostrate or erect. They are often found on the ground or attached to tree branches. 5. Lichens reproduce by : Gonidia Soredia Oidia Conidia Explanation:Soredia are small clusters of algal cells surrounded by fungal filaments. They are a common means of asexual reproduction in lichens, allowing them to disperse and colonize new areas. 6. Which of the lichen live as a crust over soil, rocks and branches of trees? Fruticose Foliose Crustose Filamentous Explanation:Crustose lichens form a crust-like growth on various substrates, including soil, rocks, and tree branches. They are tightly adhered to their substrate and are difficult to remove without damaging the lichen. 7. Lichens show : Commensalism Mycorrhiza relationship Parasitic relationship of algae and fungi Symbiosis of algae and fungi Explanation:Lichens are a classic example of symbiosis, where algae and fungi live together in a mutually beneficial relationship. The algae provide food through photosynthesis, while the fungi offer protection and structure. 8. Majority of lichens are : Basidiolichens Ascolichens None of these Phycolichens Explanation:Most lichens are classified as Ascolichens because their fungal partner belongs to the Ascomycetes group. These fungi form a symbiotic relationship with algae or cyanobacteria. 9. The lichens growing on rocks are called : Terricoulus Corticoulus None of these Saxicolous Explanation:Saxicolous lichens grow on rocks and are adapted to survive in harsh, exposed environments. They play a crucial role in weathering rocks and contributing to soil formation. 10. Helotism word is used for the symbiosis between : Pinus and fungi Algae and fungi Germ and bacteria Algae and Cycas Explanation:Helotism refers to a type of symbiotic relationship where one organism (the fungus) dominates and controls the other (the algae). This relationship is seen in lichens where the fungus provides structure and protection while the algae perform photosynthesis. 11. The foliose lichens are attached to substratum by means of : Rhizinae Roots None of these Rhizoids Explanation:Foliose lichens are attached to their substrate by rhizinae, which are root-like structures. These structures anchor the lichen to the surface and help absorb nutrients. 12. Which of the following structures help in respiration of lichens? Soredium Cephalodium Cyphella Isidium Explanation:Cyphellae are small, pore-like structures found on the lower surface of some lichens. They facilitate gas exchange, aiding in the respiration of the lichen. 13. Sweet scented lichen thalli used for making soaps, cosmetics are : Xanthoria and Physcia Everina and Ramalina None of the above Peltigera and Lobaria Explanation:Everina and Ramalina are lichens known for their pleasant fragrance. They are used in the production of soaps, perfumes, and cosmetics due to their aromatic properties. 14. Sexual reproduction of lichen is due to : Fungi Algae None of these Both Explanation:The fungal component of lichens is responsible for sexual reproduction. Fungi produce spores in specialized structures, which can then disperse and form new lichens. 15. Lichens form the first community in Xerosere Hydrosere Psammosere Halosere Explanation:Lichens are often the first organisms to colonize dry, barren environments, initiating the process of ecological succession in a xerosere. Their ability to withstand harsh conditions makes them pioneers in these areas. 16. Name the scientist who gave dual hypothesis for lichens? Theophrastus Schwendener De Bary Reininke Explanation:Simon Schwendener proposed the dual hypothesis for lichens, suggesting that lichens are a symbiotic association between fungi and algae. This hypothesis revolutionized our understanding of lichen biology. 17. On the basis of distribution of algal component in the thallus, lichens are classified as : Heteromerous Homoiomerous None of the above Homoiomerous or heteromerous Explanation:Lichens can be classified based on the distribution of their algal component within the thallus. Homoiomerous lichens have an even distribution of algae, while heteromerous lichens have a layered structure with distinct algal and fungal layers. 18. Most of the lichens are composed of : Blue-green algae and ascomycetes Blue-green algae and basidiomycetes Green algae and ascomycetes Green algae and phycomycetes Explanation:The majority of lichens consist of green algae and ascomycete fungi. This combination allows them to thrive in various environments, from arid deserts to moist forests. 19. Lichen show : Fast growth Very fast growth Normal growth Very slow growth Explanation:Lichens grow very slowly, often only a few millimeters per year. Their slow growth rate is due to their reliance on photosynthesis and the limited availability of nutrients in their environments. 20. The source of litmus is : Laminaria Roccella Lecanora Aspergillus Explanation:Litmus is a water-soluble mixture of different dyes extracted from lichens, particularly Roccella species. It is commonly used as a pH indicator in laboratories. 21. Lichens are ecologically important because : They can grow in greatly polluted areas They are associations of algae and fungi They are pioneers of vegetation in a lithosere They are symbiotic with higher plants Explanation:Lichens are among the first organisms to colonize bare rock surfaces, initiating the process of soil formation and ecological succession. They play a crucial role in breaking down rocks into soil over time. 22. Parmelia belongs to : Foliose lichens Fruticose lichens Liverworts Crustose lichens Explanation:Parmelia is a genus of foliose lichens, which have a leaf-like structure and are loosely attached to their substrate. They are commonly found on tree bark and rocks. 23. In Gymnocarpeae the fruiting body is : Perithecium Apothecium None of these Cleistothecium Explanation:The apothecium is a type of fruiting body found in certain lichens, particularly those in the Gymnocarpeae group. It is an open, often disc-shaped structure where spores are produced. 24. Lichens are the indicator of pollution : As they grow well in polluted environment As they are sensitive to pollution None of the above As they cause pollution Explanation:Lichens are sensitive to various pollutants, especially sulfur dioxide. Their presence or absence in an area can indicate the level of air pollution, making them valuable bioindicators. 25. Elongated structure on upper cortex of lichen, having some algal and fungal partners as in main thallus is : Isidium Soredium Cyphelle Cephalodium Explanation:Isidia are elongated, outgrowths on the surface of lichens that contain both algal and fungal components. They aid in vegetative reproduction and help the lichen spread. 26. Which lichen is called Reindeer moss? Cetraria islandica Cladonia rangiferina Parmelia Lecanora Explanation:Cladonia rangiferina, commonly known as Reindeer moss, is a type of lichen that serves as an important food source for reindeer and caribou in Arctic and sub-Arctic regions. 27. Fruiting body of lichens is : Perithecium Apothecium None of these Both (a) and (b) Explanation:Lichens can produce various types of fruiting bodies, including apothecia and perithecia. These structures are involved in the sexual reproduction of the fungal component of the lichen. 28. Lichens are pioneers of vegetation in a : Psammosere Hydrosere Halosere Lithosere Explanation:Lichens are often the first organisms to colonize bare rock surfaces, initiating the process of ecological succession in a lithosere. Their ability to break down rocks into soil makes them pioneers in these environments. 29. Lichens reproduce by : Gonidia Soredia Oidia Conidia Explanation:Soredia are small clusters of algal cells surrounded by fungal filaments. They are a common means of asexual reproduction in lichens, allowing them to disperse and colonize new areas. 30. Master-slave relationship between fungi and algae in the lichens is called : Epiphytism Helotism Saprophytism Parasitism Explanation:Helotism describes the master-slave relationship in lichens, where the fungus (master) controls the algae (slave). The fungus provides a protective environment, while the algae produce nutrients through photosynthesis. 31. A structure in lichen that is similar to stomata in function is : Isidium Soredium Cynanelle Cyphellae Explanation:Cyphellae are small, pore-like structures found on the lower surface of some lichens. They facilitate gas exchange, similar to the function of stomata in plants. 32. Which of the following structures help in retaining moisture? Soredia Cephalodia Syphella Isidia Explanation:Cephalodia are specialized structures in lichens that help retain moisture. They contain cyanobacteria and are often found on the surface of the lichen thallus. 33. Lichens are indicators of : Air pollution Water pollution Noise pollution Soil pollution Explanation:Lichens are highly sensitive to air quality and are used as bioindicators of air pollution. Their presence or absence can provide valuable information about the levels of pollutants in the environment. Loading …
