Students can download Class 8 Science Chapter 6 Classification of Living Organisms Important Questions, KSEEB Class 8 Science Important Questions and Answers helps you to revise the complete Karnataka State Board Syllabus and to clear all their doubts, score well in final exams.
Karnataka State Syllabus Class 8 Science Important Questions Chapter 6 Classification of Living Organisms
Question 1.
Why is there a need to classify living organisms?
Answer:
More than a million species of living organisms have been discovered and described so far. The vast number of species of organisms that have been identified and described, exhibit a great deal of variation in their form, structure, mode of life and various other aspects. Unless they are divided into discrete groups based on the differences and similarities between them, it becomes practically impossible to study them.
Question 2.
What are the advantages of classifying living organisms?
Answer:
Classifying organisms brings the following advantages:
- It makes the study of living organisms convenient and easy.
- It helps in the specific identification of any given organism.
- The study of a few representatives from each distinct group helps us to know the characteristics of the rest of the members of the group.
- It reveals the relationships among various groups of organisms.
- It provides information about plants and animals which occur in specific geographical regions.
- It indicates the evolutionary relationship by establishing the gradually increasing complexity of form and structure in different groups of organisms.
Question 3.
What is meant by classification of organisms? What is the field of study called?
Answer:
The scientific practice of identifying, naming and grouping of living organisms is called classification. The branch of biology that deals with the classification of organisms is called taxonomy.
Question 4.
Classify the following animals as herbivores and carnivores: Tiger, Cow, Elephant, Wolf, Deer, Crocodile, Squirrel and Parakeet.
Answer:
- Herbivores: Cow, Elephant, Deer, Squirrel, Parakeet.
- Carnivores: Tiger, Wolf, Crocodile.
Question 5.
Classify the following as food crops, timber plants (furniture) and medicinal plants: Tulasi, Ragi, Honne, Garlic, Teak and Potato.
Answer:
- Food-yielding plants: Ragi and Potato
- Timber-yielding plants: Honne and Teak
- Medicinal plant: Tulasi, Garlic.
Question 6.
Which Indian saint is called the ‘father of Ayurveda’? Name the book in which he has enlisted about 340 plants and about 200 types of animals.
Answer:
Charaka, an ancient Indian sage, who lived in 600 BC is called the ‘father of Ayurveda’. The book titled ‘Charaka Samhitha’ describes about 340 plant types and about 200 types of animals.
Question 7.
How did Aristotle classify living organisms?
Answer:
Aristotle classified living organisms into plants and animals.
Question 8.
Who is popularly known as the father of biology’?
Answer:
Aristotle is popularly known as the ‘father of biology’.
Question 9.
Aristotle’s classification includes both fish and whale under one group. How are they unrelated?
Answer:
Aristotle included both fish and whale under one group in his classification because both fish and whale were ‘water-dwelling’ animals.
A whale and a fish, however, have many differences. A fish does not feed its young one while a whale does. Fish is a cold-blooded animal while whale is a warm-blooded animal. Whale has lungs whereas fish has gills for breathing. Fish lay eggs while whales give birth to young ones.
Question 10.
Name at least two books written by the ancient Indian saint Parashara.
Answer:
Parashara, an ancient Indian saint, wrote several books which include ‘Vrikshaayurveda’ and ‘Krishiparashara’.
Question 11.
Who authored the book ‘Species Plantarum’? What does this book describe?
Answer:
The book ‘Species Plantarum’ published in 1753 was authored by the Swedish biologist Carolus Linnaeus. Carolus Linnaeus has described about 6000 species of plants in this book.
Question 12.
Name the book in which Carolus Linnaeus has classified various species of plants and animals.
Answer:
Carolus Linnaeus has given a detailed system of classification of organisms in his book ‘Systema Naturae’. In this book, he has classified about 4400 species of animals and about 7700 species of plants.
Question 13.
What is binomial nomenclature? Who introduced this system?
Answer:
A scientific system of naming organisms scientifically by using two terms, the first one indicating the genus and the second the species, is known as binomial nomenclature. The binomial nomenclature system of naming organisms was introduced by Carolus Linnaeus.
Question 14.
Explain the concept of binomial nomenclature.
Answer:
The modern system of naming each species of plants and animals is called binomial nomenclature. This system was developed by the Swedish botanist Carl Linnaeus. In this system each species is given a name that consists of two parts.
The first part is the name of the genus to which the species belongs. The second part is the species of the organism within the genus. The binomial nomenclature of human beings is known as Homo sapiens. Here, Homo indicates the genus of the humans and sapiens indicates the species.
Question 15.
Briefly explain Carolus Linnaeus’ contribution to the classification of organisms.
Answer:
The greatest contribution of Linnaeus to the natural system of classification is that he recognised species as the basic natural unit of classification. He proposed two kingdoms, kingdom Plantae and kingdom Animalia in his classification. He used four specific categories in his classification namely class, order, genus and species. These units of classification are in use even in the modem system of classification.
Linnaeus also introduced the scientific method of naming organisms called binomial nomenclature. It is because of these significant contributions that Linnaeus is considered as the Father of Modern Taxonomy.
Question 16.
Give the binomial nomenclature of the following: Mango, Humans, Dog and Tiger.
Answer:
Question 17.
Donkey belongs to the species ‘asinus’ while horse belongs to ‘caballus’. Both donkey and horse belong to the same genus called ‘equus’. What is the binomial nomenclature of horse and donkey?
Answer:
The donkey belongs to the genus ‘equus’ and it belongs to the species ‘asinus’. Therefore, the binomial nomenclature of donkey is Equus asinus. Similarly, horse belongs to the genus ‘equus’ and it belongs to the species ‘callabus’. Therefore, the binomial nomenclature of horse is Equus callabus.
Question 18.
Explain Carolus Linnaeus’ system of classification of organisms.
Answer:
Linnaeus classified the organisms into two kingdoms namely
- kingdom Plantae and
- kingdom Animalia.
In Linnaeus’ system of classification, the organisms in each kingdom were grouped into species, genus, order, class and kingdom. Here, species is the smallest unit of grouping while kingdom is the biggest unit.
Question 19.
Give the modern system of classification of organisms in the form of a schematic diagram.
Answer:
The modern system of classification of organisms is an extension of Linnaeus’ system of classification. The modern system of classification only adds two more categories to the Linnaeus’ system. Thus, we may say that the modern system of classification is modified Linnaean hierarchy.
In the modern system, each Kingdom is divided into smaller groups called Phyla (singular Phylum). Each phylum contains more closely related organisms. Each phylum, in turn, is subdivided into smaller groups called Classes.
A class is composed of many Orders. Each order contains a number of Families. A family of living things is made up of several Genera (singular Genus). Finally, each genus is divided into the smallest and most closely related group of organisms called the species.
Each of these groups represents a rank in the hierarchy. The smallest grouping in the taxonomy hierarchy is the species, which contains organisms that are very closely related. The biggest grouping (rank) is kingdom.
Question 20.
What is systematic position of an organism?
Answer:
The description of an organism in terms of its rank (position) at various levels in a hierarchical classification is called the systematic position of that organism.
Question 21.
Write the systematic position of mango in seven-stage classification.
Answer:
Question 22.
Write the scientific name of mango tree.
Answer:
Mango tree belongs to the genus mangifera and the species is indica. Therefore, its scientific name is Mangifera indica.
Question 23.
Give the modern hierarchical classification of human beings.
Answer:
Question 24.
What is the present number of kingdoms into which living organisms are classified? Can this number change? Why?
Answer:
Presently, the living organisms are grouped into five kingdoms. This number may change in future. This is because, more and more organisms are being discovered every day. If any of them cannot fit into the five kingdom classification, we may have to increase the number of kingdoms to accommodate the new organisms.
Question 25.
What is natural system of classification of organisms?
Answer:
The system of classification of organisms which takes into account multiple features such as anatomy, physiology, mode of reproduction, habitat and life processes is known as natural system of classification. This is a more systematic and scientific approach to classification of organisms.
Question 26.
How many kingdoms were there in Linnaeus’ classification of organisms? Name them.
Answer:
In Linnaeus’ classification, there were two kingdoms namely kingdom Plantae and kingdom Animalia.
Question 27.
Why did it become necessary to revise Linnaeus’ two kingdom classification of living organisms?
Answer:
During Linnaeus’ time, the diversity that existed in life forms was not fully known. With the discovery of different life forms which had some unique characteristics it became necessary to modify Linnaeus’ two kingdom classification.
Question 28.
Who proposed the three kingdom classification? Name the new kingdom proposed by him.
Answer:
The three kingdom classification was proposed by Ernst Haeckel in 1866. He proposed a third kingdom ‘Protista’.
Question 29.
Draw a neat sketch of euglena and label the parts.
Answer:
Question 30.
What is the difference between prokaryotes and eukaryotes?
Answer:
Prokaryotes are organisms which do not have a well formed or definite nucleus in their body cells. Eukaryotes are organisms which have a well formed or definite nucleus in their body cells.
Question 31.
Give two examples for prokaryotic organisms. In which kingdom do you place them in the classification proposed by Whittaker?
Answer:
Examples of prokaryotic organisms include bacteria and blue-green algae. In the five kingdom classification proposed by Robert Whittaker, we place these organisms under the kingdom Monera.
Question 32.
What type of organisms do you put in the kingdom protista?
Answer:
We put all single celled eukaryotic organisms in the kingdom protista. E.g., bacteria, algae, fungi, etc.
Question 33.
Why are animals included under eukaryotes?
Answer:
The cells in animals have clear, well-defined nucleus bound by the nuclear membrane. Such cells are called eukaryotic cells. The body of animals is made of eukaryotic cells. Hence, animals are included under eukaryotes.
Question 34.
Represent Whittaker’s five kingdom classification of organisms by a diagram. Give examples for
each of the five kingdoms.
Answer:
Question 35.
In which kingdom do you include multi-cellular,primitive, heterotrophic eukaryotes?
Answer:
Multi-cellular, primitive, heterotrophic eukaryotes are included in the kingdom Monera (Fungi).
Question 36.
What is the difference between plants and animals with regard to nutrition?
Answer:
Most of the plants prepare their own food with the help of sunlight. They are autotrophs. Animals depend on plants or other animals for their food and nutrition. Hence, they are heterotrophs.
Question 37.
Place the following organisms in their respective kingdoms: Deer, Paramecium, Mushroom.
Answer:
| Organism | Kingdom it belongs to |
| 1. Deer | Animalia (Metazoa) |
| 2. Paramecium | Protista |
| 3. Mushroom | Mycola |
Question 38.
Which one of the following is a prokaryotic cell, A or B? Why?
Answer:
Between A and B, B is a prokaryotic cell. This is because, it does not contain a well formed nucleus with a clear nuclear membrane.
Question 39.
Why do viruses form a separate living entity?
Answer:
Viruses do not have a cellular structure and hence they are not considered as organisms. They cannot be included either under prokaryotes or eukaryotes. Hence, viruses form a separate living entity.
Question 40.
In which kingdom of organisms are viruses placed?
Answer:
Viruses cannot be placed under any of the five kingdoms because they do not have a cell structure and hence they cannot be called organisms. Therefore, they are studied as a separate group.
Question 41.
Write notes on:
- Viruses,
- Vivoids,
- Lichens.
Answer:
- Viruses do not have a cellular structure and hence they are not considered as organisms. They have genetic material – either RNA or DNA.
- Vivoids are smaller than viruses. They have free RNA without a protein coat.
- Lichens are the products of associations of algae and fungi. They are mutually useful.
Question 42.
Why are bread moulds grouped under mycota?
Answer:
Bread moulds have plant-like cells but do not have chlorophyll. Hence they cannot synthesize their own food. They feed on decaying organic matter. Hence they are classified under the kingdom Mycota.
Multiple Choice Questions
Question 1.
The kingdom consisting of single celled, prokaryotic organisms is
(a) mycota
(b) monera
(c) plantae
(d) protista
Answer:
(b) monera
Question 2.
Viruses are denied a kingdom of their own because
(a) they are too poorly understood
(b) they are too small
(c) their genetics cannot be determined
(d) they are not organisms
Answer:
(d) they are not organisms
Question 3.
Which one of the following is the basic unit of classification of living organisms?
(a) family
(b) species
(c) genus
(d) kingdom
Answer:
(b) species
Question 4.
The most primitive organisms from among the following are
(a) Monerans
(b) Protists
(c) Fungi
(d) Algae
Answer:
(a) Monerans
Question 5.
Unicellular eukaryotes are grouped under
(a) mycota
(b) monera
(c) protista
(d) animalia
Answer:
(c) protista
Question 6.
The classification level in which classes with similar characteristics are grouped are called
(a) class
(b) phylum
(c) order
(d) taxonomy
Answer:
(b) phylum
Question 7.
Human beings are vertebrates belonging to the kingdom animalia. What is the name of humans, according to binomial nomenclature?
(a) Animalia homo
(b) Homo sapiens
(c) Sapiens erectus
(d) Animalia sapiens
Answer:
(b) Homo sapiens
Question 8.
Which of the Linnaean classification categories listed below is the highest level?
(a) genus
(b) species
(c) class
(d) order
Answer:
(c) class
Question 9.
A true nucleus is not present in
(a) multi-cellular animals
(b) multi-cellular plants
(c) fungi
(d) some bacteria and primitive algae
Answer:
(d) some bacteria and primitive algae
Question 10.
Which one of the following is grouped with whales according to modern classification of organisms?
(a) Shark
(b) Dolphin
(c) Snake
(d) Tortoise
Answer:
(b) Dolphin
Question 11.
Hierarchy of categories was introduced by
(a) Linnaeus
(b) Aristotle
(c) Whittaker
(d) Copeland
Answer:
(a) Linnaeus
Question 12.
Common name, generic name and species name are common in case of
(a) Felis
(b) Gorilla
(c) Mangifera
(d) Canis
Answer:
(b) Gorilla
Question 13.
Binomial nomenclature is
(a) not applicable to primitive organisms
(b) not accepted by a number of countries
(c) universal with one specific name to each organism
(d) universal with two specific names to each organism
Answer:
(c) universal with one specific name to each organism
Question 14.
Identify the correct sequence oftaxomic categories.
(a) Class-phylum-order-family
(b) Phylum-family-class-order
(c) Family-order-class-phylum
(d) Order-family-genus-species
Answer:
(d) Order-family-genus-species
Question 15.
Prokaryotic cells are characterised by
(a) absence of nuclear envelope
(b) presence of nuclear envelope
(c) presence of distinct chromosome
(d) absence of genetic material
Answer:
(a) absence of nuclear envelope
Question 16.
Single-celled eukaryotes belong to the kingdom
(a) mycota
(b) animalia
(c) monera
(d) protista
Answer:
(d) protista
Fill In The Blanks
1. Grouping of things on the basis of certain common characteristics is called classification
2. Protozoa belong to the kingdom Protista
3. Animals without backbone are called invertebrates
4. Most of the organisms depend directly or indirectly upon ______ for their food, green plants
5. According to modern classification, organisms such as amoeba and euglena are classified under the kingdom protista
6. The four kingdom classification of organisms was introduced by Copeland
7. Group of organisms that breed among themselves and produce fertile offspring make a species
Match The Following
Question 1.
| A | B |
| 1. Familiaris | a. Class |
| 2. Primates | b. Genus |
| 3. Anacardiaceae | c. Species |
| 4. Magnoliophyta | d. Order |
| e. Family | |
| f. Division | |
| g. Kingdom |
Answer:
1 – c, 2 – d, 3 – e. 4 – f.
Question 2.
| A | B |
| 1. Carolus Linnaeus | a. Three kingdom classification |
| 2. Robert Whittaker | b. Father of Ayurveda |
| 3. Ernst Haeckel | c. Five kingdom classification |
| 4. Copeland | d. Discovered microorganisms |
| 5. Leeuwenhoek | e. Two kingdom classification |
| 6. Charaka | f. Four kingdom classification |
| g. Binomial nomenclature |
Answer:
1 – g, 2 – c, 3 – a, 4 – f, 5 – d, 6 – b.