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Chapter Review:  

• A eukaryotic cell has membrane-bound organelles, including a nucleus, which allow cellular processes to be carried out efficiently in isolation from each other.
• Organisms which do not have a clearly demarcated nucleus and other organelles would need to have their biochemical pathways organised in very different ways.
• Nucleated cells would have the capacity to participate in making a multicellular organism because they can take up specialised functions.
• Cells that group together to form a single organism use the principle of division of labour.
• Groups of cells will carry out specialised functions.
• Organisms that perform photosynthesis are called plants. 
• Some groups of organisms which have ancient body designs that have not changed very much are called as ‘primitive’ or ‘lower’
  organisms.
• Some other groups of organisms that have acquired their particular body designs relatively recently are called ‘advanced’ or ‘higher’ organisms.
• There is a possibility that complexity in design will increase over evolutionary time, it may not be wrong to say that older organisms are simpler, while younger organisms are more complex.
• The warm and humid tropical regions of the earth, between the tropic of Cancer and the tropic of Capricorn, are rich in diversity of plant and animal life. This is called the region of megadiversity.
• Rough estimates state that there are about ten million species on the planet, although we actually know only one or two millions of them.
• All living organisms are categorised into broad categories, called kingdoms.
• There are five kindoms in the classification proposed by Whittaker: Monera, Protista, Fungi, Plantae and Animalia.
• Kingdoms further divides into phylum for animals and divisions for plants. 
•  

Text-Book Questions With Solutions:

 

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Q1. Why do we classify organisms?

ans: We classify organism so that 

(i) We could study each of the organisms in our lifetime, as classification enables easy the study of organisms. 

(ii) It is neccessary to classify the organisms into various group to study their diversities and varieties. 

(iii) we could find out the group of organisms on the basis of similarities. 

Q2. Give three examples of the range of variations that you see in lifeforms around you.

Ans: Three examples of the range of variations;

(i) We have microscopic bacteria of a few micrometre in size. While on the other hand we have blue whale and red wood trees of california of approximate sizes of 30 metres and 100 metres repectively.

(ii) Some pine trees live for thousands of years while insects like mosquitoes die within a few days.

(iii) Some organisms like plants make their own food themselves while others like animals obtain from others. 

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Q1. Which do you think is a more basic characteristic for classifying organisms?
      (a)  the place where they live.
      (b)  the kind of cells they are made of. Why?

Ans: The kind of cells they are made of is a more  basic characteristic for classifying organisms. Because,

(i) It open the way for the further division of classification.

(ii) This is the characteristics that decides the broadest divisions among living organisms.

(iii) It decides the variety in the next level. 

Q2. What is the primary characteristic on which the first division of organisms is made?

Ans: The primary characteristic is the cellular variety of organisms such as prokaryotic and eukaryotic cells. This is the basic characteristic of classification of organism.  

Q3. On what bases are plants and animals put into different categories?

Ans: Plants and animals are put into different categories on the following basis:

(i)     Organisms which have cell-wall and they make their own food i.e autotrophs are put into plants kingdom.

(ii)    Organisms which have no cell-wall and they do not make their own food i.e hetrotrophs are put into animals kingdom. 

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Q1. Which organisms are called primitive and how are they different from the so-called advanced organisms?

Ans: Organisms which have ancient body designs that have not change very much. Such organisms are called primitive organisms. On other side advanced organisms which have developed themselves and much differentiated their body design by formation of organs and organ system.  

Q2. Will advanced organisms be the same as complex organisms? Why?

Ans: Yes, advanced organisms have changed themselves in their body design. And they have quite complex body structure. Since there is a possibility that
complexity in design will increase over evolutionary time, therefore advanced organisms also gain complexity and be the same as complex organism. 

Q1. What is the criterion for classification of organisms as belonging to kingdom Monera or Protista?

Ans: Organims which are completely prokaryotes are kept in the kingdom of Monera, while the  organisms of kingdom Protista are belong to eukaryotic organisms but unicelular. This is the criterion for classification of organisms as belonging to kingdom Monera or Protista.

Q2. In which kingdom will you place an organism which is singlecelled, eukaryotic and photosynthetic?

Ans: Kingdom Protista.

Q3. In the hierarchy of classification, which grouping will have the smallest number of organisms with a maximum of characteristics in common and which will have the largest number of organisms?

Ans: Species will have smallest number of organisms with a maximum of characteristics in common and Kingdom will have largest number of organisms.

Q1. Which division among plants has the simplest organisms?

Ans: Division Thallophyta.

Q2. How are pteridophytes different from the phanerogams?

Ans: 

Pteridophytes	Phanerogams
1. They have naked embryos that are called spores. 2. The reproductive organs of plants in Pteridophytes are very inconspicuous.	1. have naked embryos that are called spores. 2. These are plants with welldifferentiated reproductive tissues.  3. Reproductive tissues that ultimately make seeds.

Q3. How do gymnosperms and angiosperms differ from each other?

Ans: 

Gymnosperms	Angiosperms
They bear necked seed. They are usually perennial, evergreen and woody.	The seeds develop inside fruit. They are flowering plants.

 

Q1. How do poriferan animals differ from coelenterate animals?

Q2. How do annelid animals differ from arthropods?

Q3. What are the differences between amphibians and reptiles?

Q4. What are the differences between animals belonging to the Aves group and those in the mammalia group?

 

 

EXERCISE:

Q1. What are the advantages of classifying organisms?

Ans: The advantages of classification of Organisms.

(i)   It tells relations among the various classes of organisms.

(ii)  It describe about the evolution of organisms.

(iii) It makes simple the study of various organisms. 

Q2. How would you choose between two characteristics to be used
for developing a hierarchy in classification?

Ans: 

(i) The characteristics which is more fundamental or basic should be choosen first.

(ii) Choose the characteristics that decide the broadest divisions among living organisms.

(iii) Chose the characteristics that would decide the variety in the next level for forming a hierarchy in a classification.

 

Q3. Explain the basis for grouping organisms into five kingdoms.

Ans: The basis for grouping organisms into five kingdoms: 

(i) On the basis of cellular structure: like prokaryotic or eukaryotic cells.

(ii) On the basis of number of cells: like unicellular or multicellular.

(iii) On the basis of presence and absent of cell wall.

(iv) Mode of nutrition, like Performing photosynthesis or getting food from outside . 

Q4. What are the major divisions in the Plantae? What is the basis
for these divisions?

Ans: The major divisions in kingdom plantae are:

1. Thallophyta 2. Bryophyta 3. Pteridophyta 4. Gymnosperms and 5. Angiosperms

The following points constitute the basis of these divisions.

(i)  The first level of classification among plants depends on whether the plant body has welldifferentiated, distinct components.

(ii) The next level of classification is based on whether the differentiated plant body has special tissues for the transport of water and other substances within it.

(iii) Further classification looks at the ability to bear seeds and whether the seeds are enclosed within fruits.

 

Q5. How are the criteria for deciding divisions in plants different
from the criteria for deciding the subgroups among animals?

Q6. Explain how animals in Vertebrata are classified into further
subgroups.

 

Additional And Important questions: 

 

SHORT-ANSWER TYPE:

Que: Who is called the father of taxonomy?

Ans: Carolus Linnaeus.

Que: Write the scientific name of human being.

Ans: Homo sapience.

Que: Write the scientific name of frog.

Ans: Rana tigrigna.

Que: Write the scientific name of cat.

Ans: Fallish domestica 

Que: Write  the scientific name of tiger.

Ans: Fallish forestica.

Que: Which is the largest phylum of animal Kingdom?

Ans: Arthropoda.

Que: Name the organisms which are outside of the classification.

Ans: Virus and Prions. 

Que: Name the phylum in which organisms have bilaterally symmetrical and segmented body and jointed leg.

Ans: Arthropoda.

Que: Name the group of animals which have spiny skinned.

Ans: Echinodermata.

Que: Give two examples of Echinodermata.

Ans: Star fish , Echinus.

Que: Name the organ of Echinodermata group of animals by which they use to move around.

Ans: Peculiar water-driven tube.

Que: By which material in Echinodermata group of animal’s skeleton is made of ?

Ans: Hard Calcium Carbonate.

Que: Which type of circulatory system does Mollusca have?

Ans: Open circulatory System.

Que: Name four animals of Mollusca group.

Ans: Snails, Unio, Octopus, chiton etc.

Que: Write one major function of Notochord.

Ans: It provides a place for muscles to attach for ease (easiness) of movement.

Que: Where are the organisms of Protochordata mainly found ?

Ans: Protochordates are marine (sea) animals.

Que : What is generally called the organisms of Porifera?

Ans : Sponges.

Que : Where are the organisms of Porifera generally found?

Ans : Marine habitats.

Que : Name two mammals which lay eggs?

Ans : Platypus and Echidna.

Que : Name the phylum of the animal kingdom whose skin is covered with scales and plates.

Ans : Pisces

Que : Name the phylum of animal kingdom which has mammary glands for production of milk to nurish their baby.

Ans : Mammals.    

Que: Where are the organisms of thallophyta found.

Ans: In water (Aquatic animal)

Que: name cell-wall made of a tough complex sugar in fungi.

Ans: Chitin.

Que: Name that organism which uses decaying organic material as food.

Ans: saprophytes.

Que: Name two organisms of fungi.

Ans: (i) Yeast    (ii) Mushrooms. 

Que: Write the name of that living group in which structures named cilia and flagella are found for moving around.

Ans: Protista group.

Que: What is the primary characteristic on which the first division of organisms is made?

Ans: cellular structure and their function.

 

 

Additional Questions with solutions:

 

SHORT-ANSWER TYPE:

 

Que. -  What is called primitive organism?

Ans. – Some groups of organisms which have ancient body designs that have not change very much. Such organisms are called primitive organisms.

Que. – What are called advanced organism?

Ans. – Some groups of organisms which have acquired their particular body designs relatively recently. Such organisms are called advanced organisms.

Que. – Define plants. 

Ans. – Those which synthesize their own food in taking part in photosynthesis process are called plants. 

Que – Define symbiotic?

Ans – Some fungal species live in permanent mutually dependent relationships with bluegreen algae (or cyanobacteria). Such relationships are called symbiotic. Ex. Lichens.

Que - Define Taxonomy. 

Ans: The branch of science that classify living organisms among different categories or group is called taxonomy. It is the science of identifying and naming species into system of classification.

Que – Which type of organisms found in Protista class. Give two example.

Ans – The organisms of unicellular Eukaryotic are found in Protista. Give two example. E x. Ameoba and Paramecium.

 

Que – What are phanerogams?

Ans – plants with well differentiated reproductive tissues that ultimately make seeds are called phanerogams.

Que – What are cryptogams?

Ans - The reproductive organs of plants in such groups are very inconspicuous, and they have hidden reproductive organs’. Therefore they are called  ‘cryptogamae’.

 

Que – What is Nomenclature?

Ans - There need for systematic naming of living organisms for identifying them as we can’t identify the organisms by their general name anywhere in the world. This is also known as scientific name. There are two names with Nomenclature, the first genus and second for species.  

 

Que – What is Notochord?

Ans – The notochord is a long rod-like support structure (chord=string) that runs along the back of the animal separating the nervous tissue from the gut.

 

Que : There are holes or pores all over the body of the Porifera organisms, What is the function of these holes?

Ans : These holes lead to a canal system that helps in circulating water throughout the body to bring in food and oxygen.

 

Que – Write the advantage of nomenclature.

Ans – we can’t identify the organisms by their general names anywhere in world. As organisms have different name in different localities. Organisms can be identified by the nomenclature (Scientific name). Nomenclature provides organisms’ scientific name.      

 

Additional Questions With Solutions

 

LONG ANSWER TYPE: 

 

Que: In How many classes Plantae is divided?

Ans:  Plantae is divided into five parts.

(i)   Thallophyta

(ii)  Pteridophyta

(iii)  Bryophyta

(iv) Gymnosperms

(v)  Angiosperms   

Que: write the properties of THALLOPHYTA.

Ans:

(i)  Plants that do not have well-differentiated body design fall in this group.

(ii)  he plants in this group are commonly called algae

(iii)  These are aquatic plants. Examples are Spirogyra, Ulothrix, Cladophora and Chara

​

Que: Write the properties of BRYOPHYTA.

Ans:

(i)  These plants are both aquatic and teristetial so this group is called the amphibian of plant kingdom.

(ii)  The plant body is commonly differentiated to form stem and leaf-like structures.

(iii)  There is no specialized tissue for the conduction of water and other substances from one part of the plant body to another.

(iv)  Examples are moss (Funaria) and Marchantia

​

Que: Write the properties of Pteridophyta.

Ans:

(i)   The plant body is differentiated into roots, stem and leaves.

(ii)  It has specialised tissue for the conduction of water and other substances.

(iii) Examples are Marsilea, ferns and horse-tails.

(iv) It has naked embryos that are called spores.

(v)  The reproductive organs of plants in all these three groups are very inconspicuous.

Que: Write the properties of gymnosperms.

Ans:  

(i)  This group bear naked seeds.

(ii)  These are usually perennial, evergreen and woody.

(iii) Examples – Pines such as Deodar , and Cycas. 

 

Que: Write the properties of angiosperms.

Ans:

(i) The seeds develop inside an organ which is modified to become a fruit.

(ii) These are also called flowering plants.

(iii) plant embryos in seeds have structures called cotyledons.

 

Que: Write two differences between Gymnosperms and Angiosperms.

Ans:

Gymnosperms	Angiosperms
They bear necked seed. They are usually perennial, evergreen and woody.	The seeds develop inside fruit. They are flowering plants.

 

Que: In How many part animalia kingdom is divided?

Ans:  Animalia kingdom is divided into two part.

(i)     Chordate

(ii)    Non chordate

 

Que: What are the advantages of classification of Organisms?.

Ans: The advantages of classification of Organisms.

(i)   It tells relations among the various classes of organisms.

(ii)  It describe about the evolution of organisms.

(iii) It makes simple the study of various organisms. 

Que : Write the difference between Pteridophyta and Phanerogams.      

Ans:   

Pteridophyta:

(i)   It has no ability to produce seeds.

(ii)  The reproductive organs are very inconspicuous (hidden).

Phanerogams:

(i)   Seeds are the result of the reproductive process.

(ii)  Reproductive tissues are well differentiated (developed).

Que: What features do All chordates possess?

Ans: All chordates possess the following features:

(i)   They have a notochord
(ii)  They have a dorsal nerve cord
(iii) They are triploblastic
(iv) They have paired gill pouches
(v)  They are coelomate.

 

Que: Explain the basis for grouping organisms into five kingdoms.

Ans: The major characteristics considered for classifying all organisms into five major kingdoms are:

(a)   whether they are made of prokaryotic or eukaryotic cells

(b)   whether the cells are living singly or organised into multicellular and thus            complex organisms

(c)   whether the cells have a cell-wall and whether they prepare their own food.