20 Questions with Answers and Explanations on “Kingdom Fungi” for Biology Students.
1. Lichens indicate SO2 pollution because they
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(a) show association between algae and fungi
(b) grow faster than others
(c) are sensitive to SO2
(d) flourish in SO2 rich environment.
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Answer and Explanation:
1. (c): Lichens are found in Artie Tundra region where no other plant can grow. Lichens prefer to grow in pollution free environment. They are often used as a indicator of pollution and also they are very sensitive to SO2. They are first to die in a polluted environment (more SO2).
2. Absorptive heterotrophic nutrition is exhibited by
(a) algae
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(b) fungi
(c) bryophytes
(d) pteridophytes.
Answer and Explanation:
2. (b): The true fungi or the eumycetes are special types of achlorophyllous thallophytic organisms living a parasitic or a saprophytic mode of existence; they are always heterophytes and never autophytes. They depend on others for food, but all other groups as algae, bryophytes and pteridophytes are chlorophyll containing green plants that are autotrophic.
3. Organisms which are indicator of SO2 pollution of air
(a) mosses
(b) lichens
(c) mushrooms
(d) puffballs.
Answer and Explanation:
3. (b): Lichens are the indicator of pollution. By studying the behaviour of lichens the type of pollution can be detected. They are the most sensitive and die in S02 rich area.
4. Mycorrhiza exhibits the phenomenon of
(a) parasitism
(b) symbiosis
(c) antagonism
(d) endemism.
Answer and Explanation:
4. (b): Association between roots of higher plants e.g pine, birch and fungal hyphae is called mycorrhiza. It exhibits the phenomenon of symbiosis. Here both the organisms in association are mutually benefitted. In this, fungal hyphae take nutrition from the plant and in return increase surface area for absorption of water and minerals for the plant. Mycorrhizal roots occur in superficial layers of the soil.
They are thick, irregular with wooly covering devoid of root hairs and root cap. They are of two types – ectomycorrhiza and endomycorrhiza. In the roots of Pinus is seen ectotrophic mycorrhiza as the root hairs are poorly developed. In ectomycorrhiza, the fungus partner is commonly a basidiomycete.
It lives in intercellular spaces of cortex and forms a thick wooly covering on the outside. In endomycorrhiza, the fungus is commonly a zygomycete. The tips of fungal hyphae pass into cortical cells producing swollen vesicles or finely branched masses called arbuscules. Endomycorrhiza is, therefore, also called VAM or vesicular-arbuscular mycorrhiza.
Outer covering is small. Parasitism is a phenomenon that involves a parasite which lives in constant association of the host and gets its food directly or indirectly without killing the host. Antagonism is the inhibition of growth of one organism by another. Endemism is the permanent occurance of an organism inside another organism.
5. The black rust of wheat is a fungal disease caused by
(a) Albugo Candida
(b) Puccinia graminis tritici
(c) Melampsora lini
(d) Claviceps purpurea.
Answer and Explanation:
5. (b): Puccinia graminis tritici belongs to basidiomycotina and causes black rust of wheat. It is internal obligate parasite. It is found everywhere, where wheat is grown. The teleutospore of the fungus causes the rust. They are produced inside teleutosori. These telia form elongated, dark brown to black pustules on the surface of stems and leaves of the wheat. Albugo Candida causes white rust of crucifers. Melampsora lini causes linseed rust. Clavicepspurpurea causes ergot of graminae.
6. Mycorrhiza is correctly described as
(a) parasitic association between roots and some fungi
(b) symbiotic relationship between fungi and roots of some higher plants
(c) symbiosis of algae and fungi
(d) relation of ants with the stem of some trees.
Answer and Explanation:
6. (b): Association between roots of higher plants and fungal hyphae is called mycorrhiza. Both the organisms are benefitted in this relationship. The fungal hyphae take nutrition from the plant and in return increase surface area for absorption of water and minerals for the plant. Mycorrhizas are found in the roots of Pinus.
7. Which one of the following statement about lichens is wrong?
(a) these grow very rapidly (2 cm per day)
(b) they show fungal and algal symbiotic relationships
(c) some of its species are eaten by reindeers
(d) these are pollution indicators.
Answer and Explanation:
7. (a): Lichens grow by extending their thallus outwards from either tips or edges. They grow very slowly. Rates of growth can vary from 0.5 mm per year to 500 mm per year. This slow growth rate equates with their long life.
8. Most of the lichens consist of
(a) green algae and ascomycetes
(b) brown algae and higher plant
(c) blue green algae and basidiomycetes
(d) red algae and ascomycetes.
Answer and Explanation:
8. (a): Lichens are peculiar dual organisms produced by the intimate association of two organisms – a fungus and an alga. The association between the two organisms is called symbiosis. On the basis of fungal partner, lichens are of 2 types:
(i) Ascolichens: In which ascomycete’s member is the fungal partner? Further in ascolichens, algal partner is mostly member of green algae and rarely blue- green algae.
(ii) Basidiolichens: Where basidiomycetes member is fungal partner. In them algal partner is generally blue-green algae. In 80% cases algal partner is member of green algae or chlorophyceae and in 20% cases, blue-green algae or myxophyceae.
Important members of green algae found in lichens are: Trebauxia, Pleurococcus, Trentepohlia and Cladophora.
9. Puccinia forms uredia and
(a) telia on wheat leaves
(b) aecia on barberry leaves
(c) pycnia on barberry leaves
(d) aecia on wheat leaves.
Answer and Explanation:
9. (a): Puccinia is a macrocyclic and heteroecious rust fungus. It produces uredia and telia stages on wheat plant. The spores produced on wheat are uredospores (stage II) and teleutospores (stage III). Uredospores can re-infect wheat but teleutospores cannot do it. Instead they give rise to basidia (stage IV).
Basidiospores infect barberry. Pycnidia (stage I) develop on the upper surface of barberry leaves. Dikaryotisation occurs. It gives rise to aecidial stage (stage zero). Aecidia develop on the lower surface of barberry leaves. They form aecidiospores which infect Wheat. Thus basidial stage is produced on ground and pyenidial and aecidial stages are produced on barberry plant.
10. Columella is a specialized structure found in the sporangium of
(a) Spirogyra
(b) Ulothrix
(c) Rhizopus
(d) none of these.
Answer and Explanation:
10. (c): Rhizopus is a saprophytic fungus that grows on dead organic matter. The mycelium is differentiated into three kinds of hyphae rhizoidal, stolons and sporangiophores.
The rhizoidal hyphae are for anchorage and absorbing food by secreting enzymes. Stolons grow horizontally over the surface of the substratum. Sporangiophores are specialized hyphae that bear a sporangium at their tip (inside columella a dome shaped sterile portion the sporangia). It helps in dispersal of spores and usually persists even after bursting of the sporangium.
11. Black rust of wheat is caused by
(a) Puccinia
(b) Ustilago
(c) Albugo
(d) Phytophthora.
Answer and Explanation:
11. (a): Black rust of wheat is caused by Puccinia gramini tritici it is heteroecious parasite which completes its life cycle in two hosts namely wheat and barberry.
12. Adhesive pad of fungi penetrate the host with the help of
(a) mechanical pressure and enzymes
(b) hooks and suckers
(c) softening by enzymes
(d) only by mechanical pressure.
Answer and Explanation:
12. (a): The adhesive pad of fungi penetrates the host with the help of mechanical pressure and enzymes. It pushes against the cell wall of the host and then releases cellulase to digest cellulose of the host cell wall so that the hypha is able to penetrate the host cell wall.
13. Which of the following secretes toxins during storage conditions of crop plants?
(a) Aspergillus
(b) PeniciIlium
(c) Fusarium
(d) Colletotrichum.
Answer and Explanation:
13. (a, b): PeniciIlium and Aspergillus both produce toxins in stored seeds and grains. Aspergillus produces aflatoxin in fruits, vegetables, food grains and seeds etc. Penicillium produces yellow rice toxins in rice, barley and corns.
14. Which fungal disease spreads by seed and flowers?
(a) loose smut of wheat
(b) corn smut
(c) covered smut of barley
(d) soft rot of potato.
Answer and Explanation:
14. (a): Loose smut of wheat infects the healthy wheat plants at the time of flowering. Here chlamydospores, from smutted heads (blown by the wind) germinate on the stigmas and produce infection threads, infecting the ovaries and stigma. Ultimately, the fungus continues to grow within the embryo, as the seed matures.
With the germination of these infected seeds, internal dormant fungal mycelium resumes its activity again. In covered smut of Barley, fungal spores are liberated out only by rupturing the wall of the grains, especially at the time of threshing. This type of infection takes place during the young seedling stage. Seedling infection occurs in covered smut of Barley. Shoot infection occurs in corn smut.
15. Which fungal disease spreads by seed and flowers?
(a) loose s.nut of wheat
(b) corn smit
(c) covered smut of barley
(d) soft rot of potato.
Answer and Explanation:
15. (a): Loose smut of wheat infects the healthy wheat plants at the time of flowering. Here chlamydospores, from smutted heads (blown by the wind) germinate on the stigmas and produce infection threads, infecting the ovaries and stigma. Ultimately, the fungus continues to grow within the embryo, as the seed matures. With the germination of these infected seeds, internal dormant fungal mycelium resumes its activity again.
In covered smut of Barley, fungal spores are liberated out only by rupturing the wall of the grains, specially at the time of threshing. This type of infection takes place during the young seedling stage. Seedling infection occurs in covered smut of Barley. Shoot infection occurs in corn smut.
16. Lichens are well known combination of an alga and a fungus where fungus has
(a) a saprophytic relationship with the alga
(b) an epiphytic relationship with the alga
(c) a parasitic relationship with alga
(d) a symbiotic relationship with alga.
Answer and Explanation:
16. (d): Lichen are peculiar dual organisms produced by the intimate association of two organisms a fungus and an alga. The association between the two organisms is symbiosis. Both the organisms are mutually benefitted in this association and are dependent on each other. The algal cell photosynthesizes with the help of chloroplast.
Therefore lichens are autotrophic. A part of these manufactured carbohydrates are used by the alga in its nutrition, the rest is supplied to the fungal partner. The fungus in turn provides water and nutrients which it absorbs from the soil using the rhizoidal hyphae. Thus 2 both the partners get benefitted from each other. The algal partner is called phycobiont and the fungal partner is called mycobiont.
17. There exists a close association between the alga and the fungus within lichen. The fungus
(a) provides protection, anchorage and absorption for the algae
(b) provides food for the alga
(c) fixes the atmospheric nitrogen for the alga
(d) releases oxygen for the alga.
Answer and Explanation:
17. (a): Refer answer 16.
18. Which of the following environmental conditions are essential for optimum growth of Mucor on a piece of bread?
A. Temperature of about 25° C
B. Temperature of about 5° C
C. Relative humidity of about 5%
D. Relative humidity of about 95%
E. A shady place
F. A brightly illuminated place
Choose the answer from the following options?
(a) B, C and F only
(b) A, C and E only
(c) A, D and E only
(d) B, D and E only
Answer and Explanation:
18. (c): Mucor is a filamentous fungus found in the humus of soil decaying fruits, vegetables. It is commonly known as black mould. Most of the Mucor sp. are unable to grow at 37°C and the strains isolated from human infections are usually one of the few thermotolerant 4, Mucor sp. colonies of Mucor grow rapidly at 25-30°C, humidity about 90-95% and quickly cover the surface of the agar. It requires moist and shady place for its growth.
Many sp. of Mucor are responsible for causing roting of fruit and vegetables. A few sp. eg. Mucor pusillus are pathogenic to man.
19. Which pair of the following belongs to basidiomycetes?
(a) Puffballs and Claviceps
(b) Peziza and stink horns
(c) Morchella and mushrooms
(d) Birds nest fungi and puffballs.
Answer and Explanation:
19. (d): The Cyathus is known as bird’s nest fungi, and Lycoperdon is called puffballs. Both these fungi belong to the group of club fungi or basidiomycetes. These fungi produce spores inside club shaped fruit bodies called basidium. Typically basidium has 4 basidiospores produced exogenously. Peziza and Morchella, Claviceps belong to ascomycetes (produce ascospores in ascocarps). Mushrooms are basidiomycete’s fungi.
20. Ergot of rye is caused by a species of
(a) Uncinula
(b) Ustilago
(c) Claviceps
(d) Phytophthora.
Answer and Explanation:
20. (c): Calviceps purpurea (ergot fungus) causes ergotism in rye. The ear of rye develops sclerotium of the fungus and contains hallucinogen such as LSD (diethyl lysergic acid). LSD induces chronic psychosis and severe damage of the central nervous system in humans and other mammals.
