NCERT Exemplars - The Living World (Part-1) NEET Notes | EduRev

MULTIPLE CHOICE QUESTIONS

Q.1. As we go from species to kingdom in a taxonomic hierarchy, the number of common characteristics
(a) Will decrease
(b) Will increase
(c) Remain same
(d) May increase or decrease
Ans. (a)
Solution.
As we go higher from species to kingdom, the number of common characteristics goes on decreasing. Lower the taxa, more are the characteristics that the members within the taxon share. Higher the category, greater is the difficulty of determining the relationship to other taxa at the same level.

Q.2. Which of the following ‘suffixes’ used for units of classification in plants indicates a taxonomic category of 'family’?
(a) —Ales
(b) —Onae
(c) —Aceae
(d) —Ae
Ans. (c)
Solution.
(a) —Ales —> Order (plant)
(b) —Onae —> Class (plant)
(c) —Aceae —> Family (plant)
(d) —Ae —> Phylum (plant)

Q.3. The term ‘systematics’ refers to
(a) Identification and study of organ systems of plants and animals
(b) Identification and preservation of plants and animals
(c) Diversity of kinds of organisms and their relationship
(d) Study of habitats of organisms and their classification
Ans. (c)
Solution.
Human beings were, since long, not only interested in knowing more about different kinds of organisms and their diversities, but also the relationships among them. This branch of study was referred to as systematics. Systematics takes into account evolutionary relationships between organisms.

Q.4. Genus represents
(a) An individual plant or animal
(b) A collection of plants or animals
(c) A group of closely related species of plants or animals
(d) None of these
Ans. (c)
Solution.
Genus comprises a group of related species which has more characters in common in comparison to species of other genera.

Q.5. The taxonomic unit ‘Phylum’ in the classification of animals is equivalent to which hierarchical level in classification of plants?
(a) Class
(b) Order
(c) Division
(d) Family
Ans. (c)
Solution.
Classes comprising animals like fishes, amphibians, reptiles, birds along with mammals constitute the next higher category called Phylum. All these classes are included in the phylum chordata. In case of plants, classes with a few similar characters are assigned to a higher category called Division.

Q.6. Botanical gardens and zoological parks have
(a) Collection of endemic living species only
(b) Collection of exotic living species only
(c) Collection of endemic and exotic living species
(d) Collection of only local plants and animals
Ans. (c)
Solution.
Botanical gardens and zoological parks have collection of endemic and exotic living species.

Q.7. Taxonomic key is one of the taxonomic tools in the identification and classification of plants and animals. It is used in the preparation of
(a) Monographs
(b) Flora
(c) Both (a) and (b)
(d) None of these
Ans. (c)
Solution.
(i) Flora contains the actual account of habitat and distribution of plants of a given area. These provide the index to the plant species found in a particular area.
(ii) Manuals are useful in providing information for identification of names of species found in an area. Monographs contain information on any one taxon, i.e. any one genus or family at a particular time. They also help incorrect identification.

Q.8. All living organisms are linked to one another because
(a) They have common genetic material of the same type
(b) They share common genetic material but to varying degrees
(c) All have common cellular organization
(d) All of the above
Ans. (b) 
Solution.
All living organisms - present, past and future are linked to one another by the sharing of the common genetic material, but to varying degrees.

Q.9. Which of the following is a defining characteristic of living organisms?
(a) Growth
(b) Ability to make sound
(c) Reproduction
(d) Response to external stimuli
Ans. (d)
Solution.
Response to external stimuli is a defining characteristic of living organisms.

Q.10. Match the following and choose the correct option.

(a) D—(i), C—(ii), E—(iii), B—(iv), A-(v)
(b) E—(i), D—(ii), B—(iii), A—(iv), C-(v)
(c) D—(C), E—(ii), B—(iii), A—(iv), C-(v)
(d) E—(i), C—(ii), B—(iii), A—(iv), D-(v) 
Ans. (a)
Solution.

VERY SHORT ANSWER TYPE QUESTIONS

Q.1. Linnaeus is considered as Father of Taxonomy. Name two other botanists known for their contribution to the field of plant taxonomy ?
Ans. Natural system of classification for flowering plants was given by George Bentham and Joseph Dalton Hooker, in three volume of Genera Plantarum.

Q.2. What does ICZN stand for?
Ans. ICZN stands for International Code of Zoological Nomenclature.

Q.3. Couplet in taxonomic key means _____
Ans. The keys are based on the contrasting characters generally in a pair called couplet. It represents the choice made between two opposite options. This results in acceptance of only one and rejection of the other.

Q.4. What is a Monograph?
Ans. Monographs contain information on any one taxon, i.e. any one genus or family at a particular time.

Q.5. Amoeba multiplies by mitotic cell division. Is this phenomena growth or reproduction? Explain.
Ans. Amoeba is a unicellular organism and mitotic cell division is therefore reproduction as it lead to the formation of two new individual cells. A parent cells divides to produce two daughter cells and the process continues in most unicellular organisms.

Q.6. Define metabolism.
Ans. The sum total of all the chemical reactions occurring in our body is metabolism.

Q.7. Which is the largest botanical garden in the world? Name a few well known botanical gardens in India.
Ans. Largest famous botanical garden of world is Royal Botanical Garden, Kew (London), England. Largest botanical garden of India is Indian Botanical Garden, Sibpur, Howrah, Kolkata, West Bengal. National Botanical Research Institute is situated at Lucknow (India)

SHORT ANSWER TYPE QUESTIONS

Q.1. A ball of snow when rolled over snow increases in mass, volume and size. Is this comparable to growth as seen in living organisms? Why?
Ans. No, this is not comparable to growth as seen in living organisms. Non-living objects like snow ball also grow if we take increase in body mass as a criterion for growth. However, this kind of growth exhibited by non-living objects is by accumulation of material on the surface (accretion). In living organisms, growth is from inside.

Q.2. In a given habitat we have 20 plant species and 20 animal species. Should we call this as ‘diversity’ or ‘biodiversity’? Justify your answer. –
Ans. In a given habitat we have 20 plant species and 20 animal species. We can call this as ‘biodiversity’. because “bio” refers to living and diversity means “variation or variety”. Each different kind of plant, animal or organism that we see, represents a species. This refers to biodiversity or the number and types of organisms present on earth.

Q.3. International Code of Botanical nomenclature (ICBN) has provided a code for classification of plants. Give hierarchy of units of classification botanists follow while classifying plants and mention different ‘Suffixes’ used for the units.
Ans.

Q.4. A plant species shows several morphological variations in response to altitudinal gradient. When grown under similar conditions of growth, the morphological variations disappear and all the variants have common morphology. What are these variants called?
Ans. These variants are called biotypes. All biotypes are similar genetically but they are different morphologically. The morphological difference happens because of the differences in abiotic factors like temperature, pH of soil, climate etc. The difference in abiotic factors is the result of different altitudinal gradients.

Q.5. How do you prepare your own herbarium sheets? What are the different tools you carry with you while collecting plants for the preparation of a herbarium? What information should a preserved plant material on the herbarium sheet provide for taxonomical studies?
Ans. Following are the various steps of preparing herbarium:
(a) Collection: This step involves collection of a particular species.
(b) Pressing: This step involves spreading the specimen and pressing it between two sheets of paper so as to preserve most of the parts.
(c) Drying: This step usually involves drying under the sun.
(d) Poisoning: Sometimes, antifungal treatment needs to be given to the specimen to preserve it for longer duration.
(e) Mounting: This step involves mounting the specimen over a herbarium sheet.
(f) Labelling: This step involves writing full information and classification of the specimen.
Different tools which need to be carried while collecting plants for the preparation of a herbarium are; digger and pruning knife, sickle, vasculum, polythene bags, old newspaper or magazine, blotting paper, plant press, field notebooks, herbarium sheets, glue, labels, etc.
The preserved material should have thorough information and classification. This should include the names of division, order, family, genus and species.

Q.6. What is the difference between flora, fauna and vegetation? Eichhornia crassipes is called as an exotic species while Rauwolfia serpentina is an endemic species in India. What do these terms exotic and endemic refer to?
Ans.  The sum of plant species in a given geographical area is called flora of that area. The sum of animal species in a given geographical area is called fauna of that area. The term ‘vegetation’ has wider scope than the term ‘flora’. Vegetation is often used for much wider geographical area than a particular ecosystem. In many cases, the term ‘vegetation’ is used for all the plants on the global scale.
Endemic Species: A species which is found only in a particular geographical area is called the endemic species for that area. For example; Rauvolfia serpentina is found only in India. So, it is an endemic species in India.
Exotic Species: A species which is not naturally found in a particular area but may be living because of careful selection and breeding or because of being imported is called an exotic species. For example, Eichhornia crassipes is native of other country but it was introduced in India. So, it is an exotic species in India.

Q.7.  A plant may have different names in different regions of the country or world. How do botanists solve this problem?
Ans.  There are many languages and even more dialects being spoken in different parts of the world. This means a plant may have different names in different regions of the country or world. This compounds the problem for anybody because nobody can remember all those names. To solve this problem, botanists have devised the system of binomial nomenclature so that a particular species can have unique name for the purpose of scientific study. A botanical name is usually composed of two terms, viz. genus name and species name. Care is taken to make a unique name for a particular species.

Q.8. Brinjal and potato belong to the same genus Solarium, but to two different species. What defines them as separate species?
Ans. “Species is a group of potentially interbreeding groups that are reproductively isolated from other such groups”. Brinjal and potato belong to the same genus Solarium, but to two different species as they are reproductively isolated.

Q.9. Properties of cell organelles are not always found in the molecular constituents of cell organelles. Justify.
Ans. All living phenomena are due to underlying interactions. Properties of tissues are not present in the constituent cells. Similarly, properties of cellular organelles are not present in the molecular constituents of the organelle but arise as a result of interactions among the molecular components comprising the organelle. These interactions result in emergent properties at a higher level of organization. This phenomenon is true in the hierarchy of organizational complexity at all levels.

Q.10. The number and kinds of organism is not constant. How do you explain this statement?
Ans. The number and kinds of organisms are variable according to the seasonal changes like, population of certain insects’ increases during rainy season. The IUCN Red List (2004) documents the extinction of 784 species (including 338 vertebrates, 359 invertebrates and 87 plants) in the last 500 years and evolution leads to the formation of new species. The number of species keeps on increasing or decreasing due to extinction, evolution and seasonal changes..