NCERT Exemplar for Class 11 Biology Chapter-2 Biological Classification (Book Solutions)

Multiple Choice Questions (MCQs)

1. All eukaryotic unicellular organisms belong to 

(a) Monera 

(b) Protista 

(c) Fungi 

(d) Bacteria 

Ans: (b) Protista 

Explanation: Monera consists of all the prokaryotic organisms and bacteria comes under Monera. Thus, options (a) and (d) are incorrect. Fungi have both unicellular as well as multicellular organisms.  So, the correct answer is Protista. 

Hence, option ‘b’ is the correct option.

2. The five-kingdom classification was proposed by 

(a) R.H. Whittaker 

(b) C. Linnaeus 

(c) A. Roxberg 

(d) Virchow 

Ans: (a) R. H. Whittaker 

Explanation: The five kingdom classification was proposed by R.H. Whittaker in 1959. The five kingdoms introduced by R.H. Whittaker are namely: Protista, Monera, Animalia, Plantae and Fungi. 

3. Organisms living in salty areas are called as 

(a) Methanogens 

(b) Halophiles 

(c) Heliophytes 

(d) Thermoacidophiles 

Ans: (b) Halophiles 

Explanation: Organisms living in salty areas are called Halophile because ‘Halo’ means ‘salt’ and phile means ‘loving’. 

Hence, option ‘b’ is the correct answer.

4. Naked cytoplasm, multinucleated and saprophytic are the characteristics of 

(a) Monera 

(b) Protista 

(c) Fungi 

(d) Slime molds 

Ans: (d) Slime molds 

Explanation: Slime molds are considered belonging to the Monera kingdom due to multinucleate character and naked cytoplasm. 

Hence, option (d) is the correct answer.

5. An association between roots of higher plants and fungi is called 

(a) Lichen 

(b) Fern 

(c) Mycorrhiza 

(d) BGA 

Ans: (c) Mycorrhiza 

Explanation: The association between the fungi and algae is called Lichen. BGA is the short form for blue-green algae and ferns belonging to Pteridophyta. 

Hence, option (c) is the correct answer. 

6. A dikaryon is formed when 

(a) Meiosis is arrested 

(b) The two haploid cells do not fuse immediately 

(c) Cytoplasm does not fuse 

(d) None of the above 

Ans: (b) The two haploid cells do not fuse immediately 

Explanation: A dikaryon is formed when two haploid cells do not fuse immediately as ‘di’ means two and ‘karyon’ means nucleus. 

Hence, option (b) is the correct answer. 

7. Contagium vivum fluidum was proposed by 

(a) D.J. Ivanowsky 

(b) M.W. Beijerinck 

(c) Stanley 

(d) Robert Hook 

Ans: (b) M.W. Beijerinck 

Explanation: Contagium vivum fluidum was proposed by Beijerinek by demonstrating that the extracts of infected tobacco plants can cause infection in healthy plants. The fluid was termed as contagium vivum fluidum.

8. Association between Mycobiont and Phycobiont are found in 

(a) Mycorrhiza 

(b) Root 

(c) Lichens 

(d) BGA 

Ans: (c) Lichens 

Explanation: The association between Mycobiont and Phycobiont is found in Lichens. The fungal components in a lichen is called Mycobiont and the algal component is called phycobiont. 

9. Difference between Virus and Viroid is 

(a) Absence of protein coat in viroid but present in virus 

(b) Presence of low molecular weight RNA in virus but absent in viroid 

(c) Both a and b 

(d) None of the above 

Ans: (a) Absence of protein coat in viroid but present in virus 

10. With respect to fungal sexual cycle, choose the correct sequence of events 

(a) Karyogamy, Plasmogamy and Meiosis 

(b) Meiosis, Plasmogamy and Karyogamy 

(c) Plasmogamy, Karyogamy and Meiosis 

(d) Meiosis, Karyogamy and Plasmogamy 

Ans: (c) Plasmogamy, Karyogamy and Meiosis 

Explanation: Plasmogamy happens first followed by Karyogamy and Meiosis at last with respect to the fungal sexual cycle. 

11. Viruses are non-cellular organisms but replicate themselves once they infect the host cell. To which of the following kingdoms do viruses belong? 

(a) Monera 

(b) Protista 

(c) Fungi 

(d) None of the above 

Ans: (d) None of the above 

Explanation: Viruses do not belong to any kingdom as they are considered to be the borderline case between non-living and living things. 

12. Members of phycomycetes are found in 

(i) Aquatic habitats 

(ii) On decaying wood 

(iii) Moist and damp places 

(iv) As obligate parasites on plants 

Choose from the following options 

(a) None of the above 

(b) (i) and (iv) 

(c) (ii) and (iii) 

(d) All of the above 

Ans: (d) All of the above 

Explanation: Phycomycetes live in aquatic habitats, places having high humidity and moisture, as obligate parasites on plants as well as on decaying wood and belong to the Fungi kingdom.

Very Short Answer Type Questions

1. What is the principle underlying the use of cyanobacteria in agricultural fields for crop improvement? 

Ans: Cyanobacteria are used in agricultural fields as they can carry out nitrogen fixation in the soil and thus help in crop improvement. 

2. Suppose you accidentally find an old preserved permanent slide without a label. In your effort to identify it, you place the slide under microscope and observe the following features: 

(a) Unicellular 

(b) Well defined nucleus 

(c) Biflagellate–one flagellum lying longitudinally and the other transversely. 

What would you identify it as? Can you name the kingdom it belongs to? 

Ans: The kingdom Protista consists of all unicellular eukaryotes. Hence, this organism belongs to Protista. 

3. How is the five–kingdom classification advantageous over the two-kingdom classification? 

Ans: In the two kingdom classification, many unrelated organisms were also placed in the same kingdom having different characteristics from one another. This issue was resolved with the introduction of five-kingdom classification by R.H. Whittaker. Example: In two kingdom classification, the bacteria were clubbed with plant kingdom previously but many bacteria are heterotrophic which lead to difference in characteristics. Now, a separate kingdom has been made for bacteria in five kingdom classification. 

4. Polluted water bodies usually have a very high abundance of plants like Nostoc and Oscillatoria. Give reasons. 

Ans: Organisms such as Nostoc and Oscillatoria get a good amount of nutrients in polluted water and hence, they often bloom in such conditions and are found in polluted water. 

5. Are chemosynthetic bacteria-autotrophic or heterotrophic? 

Ans: Chemosynthetic bacteria use chemicals as a source of energy during chemosynthesis and hence are autotrophic as they can synthesize food on their own.

6. The common name of pea is simpler than its botanical (scientific) name Pisum sativum. Why then is the simpler common name not used instead of the complex scientific/ botanical name in biology? 

Ans: The common name ‘pea’ is an English word and this could have distinct names in distinct languages. It is way more easy to keep a standard scientific name in mind as compared to other names. Therefore, instead of using simple common names; it is said to use scientific names that might seem complicated however are universally accepted. 

7. A virus is considered as a living organism and an obligate parasite when inside a host cell. But viruses are not classified along with bacteria or fungi. What are the characteristics of viruses that are similar to non-living objects? 

Ans: Characteristics of virus that are similar to non-living objects are as follows: 

(a) They possess crystalline structures that are inert outside of the living cells. 

(b) They do not consist of any cell organelle. 

8. In the five-kingdom system of Whittaker, how many kingdoms are eukaryotes? 

Ans: In the five-kingdom classification introduced by Whittaker, four kingdoms are eukaryotes which are as follows: 

(a) Protista 

(b) Fungi 

(c) Plantae 

(d) Animalia

Short Answer Type Questions

1. Diatoms are also called ‘pearls of ocean’, why? What is diatomaceous earth? 

Ans: Diatoms are known as ‘pearls of ocean’ as they are the main producers in the marine environment. Since the walls of the diatoms are made up of silica, a large amount of cell deposits is left behind in their habitat. The accumulation of these cell deposits is called diatomaceous earth. Diatomaceous earth is used for polishing and for filtration of oils and syrups due to its gritty nature. 

2. There is a myth that immediately after heavy rains in the forest, mushrooms appear in large numbers and make a very large ring or circle, which may be several metres in diameter. These are called ‘Fairy rings’. Can you explain this myth of fairy rings in biological terms? 

Ans: The mushrooms absorb nutrients from the ground through the use of mycelium. As with time, the nutrients at the centre get exhausted. So as a result, they grow in diameter and form a circle. The diameter of the ring keeps increasing every year. The ring is actually the fruiting body of the fungus and is called the ‘Fairy Ring’.

3. Neurospora - an ascomycetes fungus has been used as a biological tool to understand the mechanism of plant genetics much in the same way as Drosophila has been used to study animal genetics. What makes Neurospora so important as a genetic tool? 

Ans: The model organism to study plant genetics is Neurospora. There are a variety of characteristics of this organism that makes it ideal to be used for genetic studies. Some of these features are as follows: 

• Quick reproduction

• Easy to culture 

• Minimum media requirement for survival

4. Cyanobacteria and heterotrophic bacteria have been clubbed together in Eubacteria of kingdom Monera as per the “Five Kingdom Classification” even though the two are vastly different from each other. Is this grouping of the two types of taxa in the same kingdom justified? If so, why? 

Ans: The kingdom Monera consists of all the prokaryotes. Both the cyanobacteria and heterotrophic bacteria are prokaryotes and hence are kept in the same kingdom. The only major difference in the characteristics is the mode of nutrition between cyanobacteria and heterotrophic bacteria. So, this classification is justified. 

5. At a stage of their cycle, ascomycetes fungi produce the fruiting bodies like apothecium, perithecium or cleistothecium. How are these three types of fruiting bodies different from each other? 

Ans: The ascocarp is the fruiting body of ascomycetes. These can be further classified into three types: 

1. Apothecium 

2. Perithecium 

3. Cleistothecium

Apothecium has a saucer-shaped structure and is open from the upper side. Perithecium has a flask-like structure and has a pore-like opening. Cleistothecium is a closed structure and has no opening at all. 

6. What observable features in Trypanosoma would make you classify it under kingdom Protista? 

Ans: Trypanosoma is a unicellular organism and has a centrally located nucleus. The Trypanosoma follows asexual method of reproduction and reserves food materials in the form of granules. These characteristics of Trypanosoma make us classify it under the Protista kingdom.

7. Fungi are cosmopolitan, write the role of fungi in your daily life. 

Ans: The roles of fungi in our daily lives is as follows:

1. Fungi such as yeast helps in the fermentation process.

2. Some fungi cause dangerous diseases of plants and animals. 

3. Fungi are also used for making antibiotics.

4. Fungi also rotten food materials such as fruits and vegetables. 

Long Answer Type Questions

1. Algae are known to reproduce asexually by variety of spores under different environmental conditions. Name these spores and the conditions under which they are produced. 

Ans: Algae reproduce through asexual mode of reproduction by a variety of spores under different environmental conditions. The spores and the conditions under which they are produced are as follows: 

2. Apart from chlorophyll, algae have several other pigments in their chloroplast. What pigments are found in blue-green, red and brown algae that are responsible for their characteristic colours? 

Ans: Algae have a variety of other pigments in their chloroplast in addition to chlorophyll. The following table depicts the various pigments present in algae and colour imparted by them: 

3. Make a list of algae and fungi that have commercial value as a source of food, chemicals, medicines and fodder. 

Ans: Algae of commercial importance are as follows:

Some fungi of commercial importance: 

4. ‘Peat’ is an important source of domestic fuel in several countries. How is ‘peat’ formed in nature? 

Ans: Peat is formed by the action of bacteria on partially degraded and decayed vegetation or any other organic matter.

Formation of Peat: Peat is formed when plant or vegetation material is inhibited from decomposing fully due to acidic and anaerobic conditions. This usually happens in wet areas due to the presence of moisture. Peat is majorly composed of wetland vegetation and its main producer is Sphagnum. The modern peats are formed at high altitudes after the retreat of the glaciers at the end of the last Ice Age. The accumulation of peat is very slow, about one millimetre per year. 

Peat is an important source of domestic fuel in many countries and is also used in agriculture to add to the soil fertility. 

5. Biological classification is a dynamic and ever evolving phenomenon which keeps changing with our understanding of life forms. Justify the statement by taking any two examples. 

Ans: The fact that the biological classification of the organisms is a dynamic and ever evolving process which keeps on changing our perspective towards the various life forms. Initially, the organisms were classified into two groups broadly: Animals and Plants. This classification was done on the basis of apparent morphological features which were easy to understand. But later, scientists discovered some flaws in the classification and began thinking of a better classification of organisms. The Five kingdom classification proposed by Robert Whittaker is the widely accepted classification. 

The structural organization and phylogenetic relationship are taken into account in the five kingdom classification of organisms. As per this classification, all the prokaryotes are kept under one kingdom, i.e. Monera and all the eukaryotes have been divided into four kingdoms. All the autotrophs that practice photosynthesis have been kept under plant kingdom and all the eukaryotic heterotrophs not having any cell wall are kept under animal kingdom. However, this classification also has certain limitations. For example; the chemosynthetic autotrophs have been kept under the kingdom Protista. In recent times, some scientists have also suggested the existence of three domains of life and others have suggested a Six-Kingdom classification. Such newer attempts of classification are in tune with our changing understanding of life forms.

Benefits of NCERT Exemplar for Class 11 Biology Chapter 2

NCERT exemplar binds your concepts and increases the clarity of the topics. Chapter 2 questions from exemplar design by the expert faculties of NCERT. It brings clear images to the student’s minds and makes them understand their progress. Chapter 2 from the NCERT exemplar is an important part of the preparation as it gives you a more detailed view of the biological classification.

Download Chapter 2 Biological Classification NCERT Exemplar Solutions 

Biological classification is the scientific process. By which we group living organisms and sub-groups based on similarities and dissimilarities. Vedantu provides a PDF of the solved NCERT Exemplar questions from Chapter 2. Click on the given link to download it by signing in with your email id.

Questions in NCERT Exemplar of Class 11 Biology Chapter 2

To help students gain good marks, NCERT provides Exemplars for every subject. These questions increase the problem-solving abilities of the students. 

Exemplar includes questions different from the ones available in the NCERT textbook of class 11 Biology. It develops better knowledge of the subjects in the students. 

Types of Questions in the NCERT Exemplar Chapter 1

1. Multiple Choice Questions (MCQs)

NCERT includes Twelve MCQs. Each MCQ has given four questions, one of which is     the right one.

2. Very Short Answer Type Question

This part includes eight questions. These questions test the basic knowledge of the students.

3. Short Answer Type Question

The second chapter of the exam consists of seven short answer type questions. These questions help a student to acquire higher-order thinking skills (HOTS).

4. Long Answer Type Questions

NCERT has added five questions. All these questions help students to revise the main topics from the chapter.