CBSE – 9th Standard Science

Class 9 Question Bank Chapter 7 – Diversity in living Organism

Q1. How Aristotle classified animals?

Ans. Greek thinker Aristotle classified animals according to whether they lived on land, in water or in the air.

Q2. What is Evolution?

Ans. Most life forms that we see today have arisen by an accumulation of changes in body design that allow the organism possessing them to survive better.

Q3. What is Biodiversity?

Ans. Biodiversity means the diversity of life forms. It is a word commonly used to refer to the variety of life forms found in a particular region.

Q4. What is Megadiversity?

Ans. 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.

Q5. What is Species?

Ans. By separating organisms on the basis of a hierarchy of characteristics into smaller and smaller groups, we arrive at the basic unit of classification, which is a ‘species’.

Q6. What do you mean by Monera?

Ans. These organisms do not have a defined nucleus or organelles, nor do any of them show multi-cellular body designs.

Q7. What do you mean by Protista?

Ans. This group includes many kinds of unicellular eukaryotic organisms. Some of these organisms use appendages, such as hair-like cilia or whip-like flagella for moving around.

Q8. What is Fungi?

Ans. These are heterotrophic eukaryotic organisms. They use decaying organic material as food and are also called saprophytes.

Q9. What is Chitin?

Ans. Fungi have cell-walls made of a tough complex sugar called chitin.

Q10. What are Lichens?

Ans. Some fungal species live in permanent mutually dependent relationships with blue green algae. Such relationships are called symbiotic. These symbiotic life forms are called lichens.

Q11. What are Plantae?

Ans. These are multicellular eukaryotes with cell walls. They are autotrophs and use chlorophyll for photosynthesis.

Q12. What is Animalia?

Ans. These include all organisms which are multicellular eukaryotes without cell walls.

Q13. What do you mean by Thallophyta?

Ans. Plants that do not have well-differentiated body design fall in this group. The plants in this group are commonly called algae.

Q14. What is Bryophyta?

Ans. These are called the amphibians of the plant kingdom. The plant body is commonly differentiated to form stem and leaf-like structures.

Q15. What is Pteridophyta?

Ans. In this group, the plant body is differentiated into roots, stem and leaves and has specialized tissue for the conduction of water and other  substances from one part of the plant to another. It has naked embryos called Spores.

Q16. What do you mean by Cryptogamae?

Ans. The reproductive organs of plants in all thallophytes, the bryophytes and the pteridophytes are very inconspicuous, and they are therefore called Cryptogamae.

Q17. What are Phanerogams?

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

Q18. What is Gymnosperms?

Ans. The plants of this group bear naked seeds and are usually perennial, evergreen and woody.

Q19. What is Angiosperms?

Ans. The seeds develop inside an organ which is then modified to become a fruit. These are also called flowering plants.

Q20. What are Cotyledons?

Ans. The seeds develop inside an organ which is modified to become a fruit. These are also called flowering plants.

Q21. What is Monocot?

Ans. Plants with seeds having a single cotyledon are called monocotyledonous or monocots.

Q22. What is Dicot?

Ans. Plants with seeds having two cotyledons are called dicots.

Q23. What are Animalia?

Ans. These are organisms which are eukaryotic, multicellular, heterotrophic and mobile. Their cells do not have cell-walls.

Q24. What is Porifera?

Ans. The word Porifera means organisms with holes. These are non-motile animals attached to some solid support. They are commonly called sponges.

Q25. What is Cnidaria?

Ans. These are animals living in water. They show more body design differentiation. There is a cavity in the body.

Q26. What are Plathylminthes?

Ans. The body of animals in this group is far more complexly designed than in the others. The body is bilaterally symmetrical.

Q27. What do you mean by triploblastic?

Ans. There are three layers of cells from which differentiated tissues can be made, which is why such animals are called triploblastic.

Q28. What are Flatworms?

Ans. The body is flattened from top to bottom, which is why these animals are called flatworms. They are either freeing living or parasitic.

Q29. What are Nematoda?

Ans. The body is cylindrical rather than flattened. There are tissues, but no real organs, although a sort of body cavity or a pseudocoelom, is present.

Q30. Who are Annelida?

Ans. They have a true body cavity which allows true organs to be packaged in the body structure.

Q31. What are Arthropoda?

Ans. In this group there is an open circulatory system, and so the blood does not flow in well defined blood vessels. The coelomic cavity is blood-filled. They have jointed legs.

Q32. What is Mollusca?

Ans.  In this group the coelomic cavity is reduced, little segmentation and has an open circulatory system and kidney-like organs for excretion.

Q33. What is Echinodermata?

Ans. These are spiny skinned organisms. These are exclusively free-living marine animals. They are triploblastic and have a coelomic cavity.

Q34. What is Protochordata?

Ans. They show a new feature of body design, namely a notochord.

Q35. What is Notochord?

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

Q36. What are Vertebrata?

Ans. These animals have a true vertebral column and internal skeleton, allowing a completely different distribution of muscle attachment points to be used for movement.

Q37. Into how many types Vertebrates are grouped into?

Ans. Vertebrates are grouped into five classes.

Q38. What are Pisces?

Ans. These are fishes exclusively aquatic animals. Their skin is covered with scales. They obtain oxygen dissolved in water by using gills. The body is streamlined, and a muscular tail is used for movement.

Q39. What is Amphibia?

Ans. These animals differ from the fish in the lack of scales, in having mucus glands in the skin, and a three-chambered heart. Respiration is through either gills or lungs.

Q40. What do you mean by Reptilia?

Ans. These animals are cold-blooded, have scales and breathe through lungs. While most of them have a three-chambered heart.

Q41. What are Aves?

Ans. These are warm-blooded animals and have a four-chambered heart. They lay eggs. There is an outside covering of feathers, and two forelimbs are modified for flight.

Q42. What is Mammallia?

Ans. Mammals are warm-blooded animals with four-chambered hearts. They have mammary glands for the production of milk to nourish their young. Their skin has hairs as well as sweat and oil glands.

Q43. What do you mean by Scientific name of an organism?

Ans. The scientific name for an organism is unique. The system of scientific naming or nomenclature we use today was introduced by Carolus Linnaeus in the eighteenth century.


  • Which division among plants has the simplest organisms?
  • How are pteridophytes different from the phanerogams?
  • How do gymnosperms and angiosperms differ from each other
  • What are the advantages of classifying organisms?
  • How would you choose between two characteristics to be used for developing a hierarchy in classification?
  • Explain the basis for grouping organisms into five kingdoms.
  • What are the major divisions in the Plantae? What is the basis for these divisions?
  • How are the criteria for deciding divisions in plants different from the criteria for deciding the subgroups among animals?
  • Explain how animals in Vertebrata are classified into further subgroups