Diversity in Living Organisms class 9 biology MCQ & SAQ

Diversity in Living Organisms class 9 biology NCERT solution

Q1. Why do we classify organisms?

Ans. We classify organisms for easier and convenient study of a variety of lifeforms.

 

Q2. Give three examples of the range of variations that you see in life-forms around you.

Ans. (a) Small cat and big cow

(b) Grass and banyan tree

(c) Black crow and green parrot

 

Q3. 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. Classification based on the kind of cells they are made of is more basic as there can be wide variations in organisms living in a given place, hence it can’t be a basic characteristic of classifying organisms.

 

Q4. What is the primary characteristic on which the main broad division of organisms is made?

Ans. Nature of cells is the primary characteristic on which the main broad division of organisms is decided.  Based on this criterion, life forms can be classified into prokaryotes or eukaryotes.

 

Q5. On what bases are plants and animals put into different categories?

Ans. Mode of nutrition and presence or absence of cell walls.

 

Q6. Which organisms are called primitive and how are they different from the so-called advanced organisms?

Ans. Organisms with simple cellular structure and no division of labor are called primitive.

Advanced organisms, like mammals, have millions of cells and there are different organs and organ systems for different biological functions.

 

Q7. Will advanced organisms be the same as complex organisms? Why?

Ans. Yes, advanced organisms means greater degree of evolution which leads to more complexity.

 

Q8. What is the criterion for classification of organisms as belonging to the kingdom Monera or Protista?

Ans. It is the presence or absence of a well defined nucleus. Monera has no nuclear membrane, while Protista shows a well defined nucleus.

 

Q9. In which kingdom will you place an organism which is single-celled, eukaryotic and photosynthetic?

Ans. Protista.

 

Q10. 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. In the hierarchy of classification, species will have the smallest number of organisms with a maximum of characteristics in common and the kingdom will have the largest number of organisms.

 

Q11. Which division among plants has the simplest organisms?

Ans. Thallophyta or algae.

 

Q12. How are pteridophytes different from the phanerogams?

Ans. Pteridophytes have naked embryos and inconspicuous reproductive organs whereas phanerogams have well-differentiated reproductive organs and covered embryos.

 

Q13. How do gymnosperms and angiosperms differ from each other?

Ans. Seeds are naked in gymnosperms and are covered in angiosperms.

 

Q14. How do porifera animals differ from coelenterate animals?

Ans. – Animals from Porifera show cellular level of organization, while those from Coelenterata show tissue level of organization.

– In Porifera there is no division of labor, while in Coelenterata some division of labor is seen.

– Porifera do not have coelom, while coelenterates have coelom.

 

Q15. How do annelid animals differ from arthropods?

Ans.

Arthropoda	Annelida
Exoskeleton present.	No skeleton.
Body is segmented into the head, thorax and abdomen.	Body is segmented into rings.
Sexes are usually separate.	Sexes may be united (Hermaphrodite) or separate.

 

Q16. What are the differences between amphibians and reptiles?

Ans.

Amphibia	Reptilia
1. Adapted to live in water and land, can breathe by skin in water.	Can live in water but needs to come to the surface to breathe in oxygen.
2. Skin is moist and soft.	Skin is hardened.
3. Respiration is either through gills or lungs.	Respiration is through the lungs.
4. Can jump.	Move by crawling.
5. Development is indirect through the tadpole stage.	Development is direct with no intermediate stage in life cycle

 

Q17. What are the differences between animals belonging to the Aves group and those in the mammalia group?

Ans.

Amphibia	Reptilia
1. Body is covered with feathers.	Body is covered with hair.
2. Beak is present, teeth absent.	Teeth present, beak absent.
3. Forelimbs modified for flying.	Forelimbs modified for various activities.
4. Hollow bones for flying.	No hollow bones.
5. Streamlined body.	Body is not streamlined, except in whales, dolphins.

 

 

NCERT Textual Questions Solved

Q1. What are the advantages of classifying organisms?

Ans. Advantages of classification:

– Better categorization of living beings based on common characters.

– Easier study for scientific research.

– Better understanding of human’s relation and dependency on other organisms.

– Helps in cross breeding and genetic engineering for commercial purposes.

 

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

Ans. Gross character will form the basis of the start of the hierarchy and fine character will form the basis of further steps of the single hierarchy.

Example:

– Presence of the vertebral column in human beings can be taken under the vertebra.

– Presence of four limbs makes them members of Tetrapoda.

– Presence of mammary glands keeps them under mammals.

 

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

Ans. Basis of Classification:

(a) Number of cells: unicellular or multicellular.

(b) Complexity of cell structure : Prokaryote & Eukaryote.

(c) Presence or absence of cell wall

(d) Mode of nutrition

(e) Level of organization

 

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

Ans. Major Divisions of Kingdom Plantae:

Division	Basis for classification
Thallophyta or Algae	Thallus-like body, plant body is not differentiated into  roots, stems etc.
Bryophyta	Body is divided into leaf and stem, lacking vascular tissue.
Pteridophyta	Body is divided into root, stem and leaf, lacking seeds.
Gymnosperm	Seed bearing, naked seeds, lack flowers.
Angiosperm	Seed bearing covered seeds produce flowers.

 

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

Ans. In plants basic structure of their body is a major criteria based on which Thallophytes are different from Bryophytes. Apart from this absence or presence of seeds is another important criteria. Gymnosperms and angiosperms are further segregated based on if seeds are covered or not. It is clear that it is the morphological character which makes the basis for classification of plants.

In animals classification is based on more minute structural variations. So in place of morphology, cytology forms the basis. Animals are classified based on layers of cells, presence or absence of coelom. Further higher the hierarchy animals are classified based on presence or absence of smaller features, like presence or absence of four legs.

 

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

Ans. Vertebrata is divided into two superclasses, viz. Pisces and Tetrapoda. Pisces have streamlined bodies with fins and tails to assist in swimming. Animals of Tetrapods have four limbs for locomotion.

Tetrapoda is further classified into following classes:

(a) Amphibia: Are adapted to live in water and on land. Can breathe oxygen through skin when under water.

(b) Reptilia: These are crawling animals. Skin is hard to withstand extreme temperatures.

(c) Aves: Forelimbs are modified into wings to assist in flying. Beak is present. Body is covered with feathers.

(d) Mammalia: Mammary glands present to nurture young ones. Skin is covered with hair. Most of the animals are viviparous.

Diversity in Living Organisms class 9 biology MCQ 

Question: What is the phylum of Octopus?

• a) Mollusca

• b) Arthropoda

• c) Annelida

• d) Cnidarian

Answer: Mollusca 

Question: What is the mode of nutrition in bacteria?

• a) Autotrophic and heterotrophic

• b) Autotrophic

• c) Heterotrophic

• d) None of the options

Answer: Autotrophic and heterotrophic 

Question: What does a bacteria lack?

• a) Endoplasmic reticulum

• b) DNA

• c) Cell wall

• d) Cytoplasm

Answer: Endoplasmic reticulum 

Question: Which of the these are found filamentous

• a) Spirogyra

• b) Euglena

• c) Chlamydomonas

• d) Amoeba

Answer: Spirogyra 

Question: In which organism flame cells form the excretory system?

• a) Flatworms

• b) Earthworms

• c) Insects

• d) Crabs

Answer: Flatworms 

Question: Choose the vascular plants out of these

• a) Ferns

• b) Mosses

• c) Liverworts

• d) Hornworts

Answer: Ferns 

Question: Which sub group in the plant kingdom produces flowers?

• a) Angiosperms

• b) Fungi

• c) Mosses

• d) Ferns

Answer: Angiosperms 

Question: The excretory system in annelids consists of tubes called?

• a) Nephridia

• b) Flame cells

• c) Metanephridia

• d) Protonephridia

Answer: Nephridia 

Question: What is not poisoning among these?

• a) Crab

• b) Scorpion

• c) Centipede

• d) Spider

Answer: Crab 

Question: What does Arthropod mean?

• a) Jointed legs

• b) Bonus legs

• c) Cartilaginous legs

• d) Largest legs

Answer: Jointed legs

Question: What is not possessed by bacteria?

• a) All of the options

• b) Membrane bound organelles

• c) Nucleus

• d) Nucleolus

Answer: All of the options

 

Question: The mode of nutrition in fungi

• a) Saprotrophic or parasitic

• b) Only saprotrophic

• c) Only parasitic

• d) None of the options

Answer: Saprotrophic or parasitic

 

Question: What is the exclusive marine phylum?

• a) Echinodermata

• b) Porifera

• c) Cnidarians

• d) Protozoa

Answer: Echinodermata

 

Question: Which phylum of animals is also called flatworms?

• a) Platyhelminthes

• b) Porifera

• c) Coelenterata

• d) Nematoda

Answer: Platyhelminthes

 

Question: In which the reproductive organs are hidden?

• a) Cryptogamae

• b) Phanerogamae

• c) Gymnosperms

• d) Angiosperms

Answer: Cryptogamae

 

Question. Which among the following produce seeds?

(a) Thallophyta

(b) Bryophyta

(c) Pteridophyta

(d) Gymnosperms

Answer :   D

Question ………………. Is a living organism which does not lived in sea water

(a) Corals

(b) Cactus

(c) Whales

(d) Octopus

Answer :   B

Question. Which among the following is a common feature of chordates?

(a) Presence of notochord

(b) Presence of triploblastic condition

(c) Presence of coelom

(d) Presence of gill pouches

Answer :   A

Question. In which group of animals, coelom is filled with blood?

(a) Arthropoda

(b) Annelida

(c) Nematoda

(d) Echinodermata

Answer :   A

Question.Find out the false statement.

(a) Aves are warm-blooded, egg-laying and have a four-chambered heart.

(b) Aves have a feather covered body, their forelimbs are modified as wings and breathe through their lungs.

(c) Most of the mammals are viviparous.

(d) Fishes, amphibians and reptiles are oviparous.

Answer :   D

Question.The locomotory organs of Echinodermata are

(a) tube feet

(b) muscular feet

(c) jointed legs

(d) parapodia

Answer :   A

Question. Choose the option that best describes the characteristics of the kingdom to which the mushroom belongs:

(a) Unicellular prokaryotic organisms

(b) Saprophytic, eukaryotic, multicellular organisms

(c) Unicellular eukaryotic organisms

(d) Autotrophic eukaryotic organisms

Answer :   B

Question. Organisms which makes their own food called……….

(a) Autotrophic

(b) Heterotrophic

(c) Consumer

(d) Decomposer

Answer :   A

Question. The book Systema Naturae was written by

(a) Linnaeus

(b) Haeckel

(c) Whittaker

(d) Robert Brown

Answer :   A

Question.…………………. Is flowering plants

(a) Phanerogams

(b) Bryophyte

(c) Angiosperm

(d) Gymnosperm

Answer :   C

Question. Well defined nucleus is absent in

(a) blue green algae

(b) diatoms

(b) algae

(d) yeast

Answer :   A

Question. Which phylum of animals is also called flatworms?

(a) Porifera

(b) Coelenterata

(c) Platyhelminthes

(d) Nematoda

Answer :   C

Question. What does Arthropod mean?

(a) bonus legs

(b) cartilaginous legs

(c) largest legs

(d) jointed legs

Answer :   D

Question. Sycon is the example of …………….. from Animalia

(a) Porifera

(b) Dicots

(c) Cnidarian

(d) Platyhelminthes

Answer :   A

Question. In which organism flame cells form the excretory system?

(a) flatworms

(b) earthworms

(c) insects

(d) crabs

Answer :   A

Question. Among the following choose the correct option that best describes the characteristics of spirogyra(a)

(a) Multicellular, autotrophic, root-like rhizoids.

(b) Cytoplasmic strands, autotrophic, presence of rhizome.

(c) Presence of male cones, nonvascular, filaments.

(d) Filamentous, presence of Cytoplasmic strands, presence of pyrenoids.

Answer :   D

Question. Autotrophs uses ……………. For photosynthesis

(a) Monera

(b) Protista

(c) Chlorophyll

(d) Oxygen

Answer :   C

Question……………………. Runs along the back of animal separating the nervous tissue from the gut

(a) Cilia

(b) String

(c) Notochord

(d) Bones

Answer :   C

Question. Hydra is the example of……………….. from Animalia

(a) Human being

(b) Cactus

(c) Dicots

(d) Cnidaria

Answer :   D

Question. What is the phylum of Octopus?

(a) Arthropoda

(b) Mollusca

(c) Annelida

(d) cnidarian

Answer :   B

Question. Pteridophyta with hidden reproductive organs called………….

(a) Thallophyta

(b) Bryophyte

(c) Angiosperm

(d) Cryptogams

Answer :   C

Question. Worms causing elephantiasis

(a) Bacteria

(b) Virus

(c) Filarial worms

(d) Pinworms

Answer :   C

1. Which among the following is a common feature of chordates?

(a) Presence of notochord

(b) Presence of triploblastic condition

(c) Presence of coelom

(d) Presence of gill pouches

► (a) Presence of notochord

2. Which of the following organisms is not triploblastic?

(a) Tapeworm

(b) Roundworm

(c) Jellyfish

(d) Liver Fluke

► (c) Jellyfish

3. Who proposed artificial system of classification

(a) John Ray

(b) Lamarck

(c) Linnaeus

(d) Wallace

► (c) Linnaeus

4. Corals are  

(a) Poriferans attached to some solid support

(b) Cnidarians, that are solitary living

(c) Poriferans present at the sea bed    

(d) Cnidarians that live in colonies

► (d) Cnidarians that live in colonies

5. Sound producing organ in birds is :-

(a) Trachea

(b) Pneumatic bones

(c) Syrinx

(d) Plumage

► (c) Syrinx

6. In which phylum pseudocoelom is present ?

(a) Coelenterata

(b) Annelida

(c) Aschelminthes

(d) Mollusca

► (c) Aschelminthes

7. Which of the following is not a feature of flatworms?

(a) Bilateral symmetry

(b) Pseudocoelomate

(c) Dorsiventrally flattened

(d) Triploblastic

► (b) Pseudocoelomate

8. Which of the following organisms shows the presence of jointed appendages?

(a) Pila

(b) Spider

(c) Sea-cucumber

(d) Chiton

► (b) Spider

9. Which of the following is a member of Phylum Echinodermata?

(a) Lionfish

(b) Starfish

(c) Jellyfish

(d) Sawfish

► (b) Starfish

10. One of the following is not an Annelid.

(a) Nereis    

(b) Earthworm    

(c) Leech    

(d) Urchins

► (d) Urchins

11. Who classified animals according to their habitat (air, water or land)?

(a) Socrates

(b) Aristotle

(c) Linnaeus

(d) Plato

► (b) Aristotle

12. Meena and Hari observed an animal in their garden. Hari called it an insect while Meena said it was an earthworm. Choose the character from the following which confirms that it is an insect.

(a) Bilateral symmetrical body 

(b) Body with Joint leg

(c) Cylindrical body

(d) Body with little segmentation

► (b) Body with Joint leg

13. Which of the following is not a bony fish ?

(a) Labeo rohita

(b) Anabas

(c) Hippocampus

(d) Chimera

► (d) Chimera

14. On the basis of origin of mouth, animals have been categorized into

(a) Deuterostomia and protozoa

(b) Protostomia and deuterostomia

(c) Protozoa and metazoa

(d) Protostomia and metazoa

► (b) Protostomia and deuterostomia

15. Canal system is present in phylum:

(a) Porifera

(b) Cnidaria

(c) Echinodermata

(d) Protozoa

► (a) Porifera

16. Skin is kept moist in earthworms. It helps in

(a) Locomotion

(b) Respiration

(c) Protection

(d) Both (a) and (b)

► (b) Respiration

17. Earthworm has an unsegmented band called :

(a) Clitellum

(b) Cephalothorax

(c) Thorax

(d) Metathorax

► (a) Clitellum

18. Which of the following is not the characteristic of animals?

(a) Eukaryotic

(b) Heterotrophic

(c) Multicellular

(d) Photosynthetic

► (d) Photosynthetic

19. The locomotory organs of Echinodermata are

(a) tube feet

(b) muscular feet

(c) jointed legs

(d) parapodia

► (a) tube feet

20. How many germ layers are present in the embryo of a highly advanced animal?

(a) 1

(b) 2

(c) 4

(d) 3

► (d) 3

21. Which phylum has a reduced coelomic cavity?

(a) Phylum Nematoda

(b) Phylum Echinodermata

(c) Phylum Arthropoda

(d) Phylum Mollusca

► (d) Phylum Mollusca

22. The first wall layer of cell is :-

(a) Tertiary wall, if present

(b) Secondary wall

(c) Primary wall

(d) Middle lamella, if present

► (c) Primary wall

23. Animals having identical right and left sides are also known as

(a) Radially symmetrical

(b) Bilaterally symmetrical

(c) Laterally symmetrical

(d) Asymmetrical

► (b) Bilaterally symmetrical

24. Which of the following is incorrectly matched ?

(a) Porifera - Sycon

(b) Coelenterata - Hydra

(c) Platyhelminthes - Fasciola

(d) Nematoda - Taenia solium

► (d) Nematoda - Taenia solium

25. Organ system grade of body organization is found in :-

(a) Sponges

(b) Protozoa

(c) Arthropodes

(d) Platyhelminthes

► (c) Arthropodes

26. Which of the following phyla possess radial symmetry?

(a) Phylum Coelenterata

(b) Phylum Platyhelminthes

(c) Phylum Nematoda

(d) Phylum Annelida

► (a) Phylum Coelenterata

27. Binomial system of nomenclature means that every organism has:

(a) a name given by two scientists

(b) one scientific name consisting of a generic name and a specific name

(c) one scientific name and one popular name

(d) a number in an international catalog by which an organism is identified

► (b) one scientific name consisting of a generic name and a specific name

28. Stinging cell organelles - nematocysts are found only in:

(a) Phylum - Coelenterata

(b) Phylum - Porifera

(c) Phylum - Echinodermata

(d) Phylum - Arthropoda

► (a) Phylum - Coelenterata

29. In which class birds are included ?

(a) Amphibia

(b) Pisces

(c) Reptilia

(d) Aves

► (d) Aves

30. Which of the following have cells that are properly arranged into tissues and organs?

(a) Parazoa

(b) Fungi

(c) Monera

(d) Eumetazoa

► (d) Eumetazoa

31. In Whiitaker’s classification, unicellular eukaryotic organisms are grouped under

(a) Protozoa

(b) Porifera

(c) Fungi

(d) Protista

► (d) Protista

32. Pteridophyta do not have  

(a) root

(b) stem

(c) flowers

(d) leaves

► (c) flowers

33. Which of the following is a diploblastic organism?

(a) Tapeworm

(b) Sea anemone

(c) Earthworm

(d) Planaria

► (b) Sea anemone

34. Balanoglossus is an example of:

(a) Urochordata

(b) Cephalochordata

(c) Protochordata

(d) Vertebrata

► (c) Protochordata

35. Mosquito belongs to the phylum

(a) Mollusca

(b) Chordate

(c) Arthropod

(d) Annelid

► (c) Arthropod

36. In Earthworm the body is divisible into :

(a) 30-35 segments

(b) 70-75 segments

(c) 90-100 segments

(d) 100-120 segments

► (d) 100-120 segments

37. The correct order of the biological hierarchy from Kingdom to Species is

(a) Kingdom, Phylum, Order, Family, Class, Genus, Species

(b) Kingdom, Phylum, Class, Order, Family, Genus, Species

(c) Kingdom, Class, Family, Order, Phylum, Genus, Species​

(d) Kingdom, Class, Order, Phylum, Family, Genus, Species

► (b) Kingdom, Phylum, Class, Order, Family, Genus, Species

38. Well defined nucleus is absent in 

(a) blue green algae

(b) diatoms    

(c) algae    

(d) yeast

► (a) blue green algae

Diversity in Living Organisms class 9 biology SAQ

Which organisms are called primitive ? How are they different from the advanced organisms ? [SAII-2014]

Answer.

Primitive organisms: Organisms which have simpler ancient body designs that have not changed much over evolutionary time are called primitive organisms.

Advanced organisms : Organisms which have complex body designs that have changed over evolutionary time are called advanced organisms.

identify the group comprising specialized tissue for the conduction of water in the plant body. Name one such plant. [SAII-2014]

Answer. The group pteridophyta shows specialized tissue for the conduction of water in the plant body. Marsilea is one such plant that belongs to this group.

Name the type of flowers that can be seen in a: (i) Monocot plant, (ii) Dicot plant.

Answer.

(i) Monocot plant: Trimerous flower having one cotyledon in the seed.

(ii)Dicot plant: Pentamer Qips flower having two cotyledons in the seed.

State which were the first terrestrial plants ? Mention two characteristic features of these plants.

Answer.

(a) Bryophyta are the first terrestrial plants. These are called the “amphibians of the plant kingdom.

(b) The two characteristics features of these plants are :

(i) The plant body is commonly differentiated into stem and leaf-like structures.

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

What are Phanerogams ? Name its two groups along with the criteria of division. [SAII-2013]

Answer.

The plants with well differentiated reproductive tissues that ultimately make seeds are called phanerogams. Seeds are the result of the reproductive process. They consist of the embryo along with the stored food, which serves for the initial growth of the embryo during germination.

The phanerogams are further divided into two groups, based on whether the seeds are naked or enclosed within fruits – gymnosperms and angiosperms.

Name the phylum to which the following organisms belong.

(a) Earthworm (6) Planaria (c) Sycon

(d) Starfish (e) Housefly (f) Octopus

Answer.

(a) Earthworm-Annelida

(b) Planaria – Platyhelminthes

(c) Sycon – Porifera

(d) Starfish – Echinodermata

(e) Housefly – Arthropoda

(f) Octopus – Mollusca

Write three characteristics each of the following groups of animals: [SAll-2012, 2014]

(a) Platyhelminthes (b) Nematoda

Answer.

(a) Platyhelminthes:

(i) The body is bilaterally symmetrical.

(ii) They are triploblastic.

(iii) Body is flattened dorsiventrally.

(b) Nematoda:

(i) Body is bilaterally symmetrical.

(ii)They are triploblastic.

(iii)Body is cylindrical.

Name the following:

(a) An egg laying mammal.

(b) A reptile with four chambered hearts.

(c) Scientist who proposed the five kingdom classification.

(d) A mammal which can fly.

(e) An aquatic mammal.

(f) Group of animals having fins for locomotion.

Answer.

(a) Platypus, (b) Crocodile, (c) Robert Whittaker, (d) Bat, (e) Whale, (f) Pisces.

 Out of the various phyla under animal kingdom, choose the one that fits the given description. Also give an example in each case:

(a) Have dorsoventrally flattened body.

(b) Water driven tube system is present for locomotion.

(c) Mostly with shells, some are without shells.

(d) Holes are present all over the body.

(e) Longest phylum due to a variety of adaptation. [SAII-2013, 2014]

Answer.

(a) Platyhelminthes (Planaria),

(b) Echinodermata (Starfish),

(c) Mollusca (Pila)

(d) Porifera (Sycon),

(e) Arthropoda (Spiders)

What do you understand about nomenclature ?

(b) Who introduced this system ?

(c) Give any four conventions while writing scientific names.

Answer.

(a) Nomenclature is the system of scientific naming of living beings so that they can be uniformly identified all over the world.

(b) The system of scientific naming was introduced by Carolus Linnaeus.

(c) Conventions:

(i) The name of the genus begins with a capital letter.

(ii) The name of a species begins with a small letter.

(iii) When printed, the scientific name is typed in italics.

(iv) When written by hand, the genus name and species names have to be underlined

What was the modification introduced by Woese in the kingdom of Monera ? [SAII -2012]

Answer. Carl Woese modified the Kingdom Monera by dividing it into Archae-bacteria and Eubacteria.

Define the term hermaphrodite. Give one example [SAII – 2014]

Answer. A hermaphrodite is an organism that has both male and female genitalia.

Example: Earthworm.

What do you understand by diploblastic ? Give one example of an organism which is diploblastic. [SAII -2014]

Answer. Diploblastic is a condition of the blastula in which there are two primary germ layers — the ectoderm and the endoderm.

Example: Jellyfish.

a pore bearing organism like creature ‘A’ belongs to a phylum ‘B’ of kingdom Animalia. Identify ‘A and B’ [SAII- 2014]

Answer. A — Sponges, B — Porifera.

Homo sapiens is the scientific name of human beings. What do these two terms imply ? [SAII – 2014]

Answer. Homo sapiens : Homo is the humangenus and sapiens is the only surviving species of the genus Homo.

write the scientific names correctly (i) panthera tigris (ii) periplaneta Americana. [SAII – 2014]

Answer. (i) Panthera tigris (ii) Periplaneta americana.

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

Answer. The primary characteristics on which the first division of organisms is made in : Do the cells

occur singly or are they grouped together and do they live as an indivisible group

 Which division among plants has the simplest organisms ?

Answer. The division ‘Thallophyta’ among plants has the simplest organisms as they do not have well- differentiated body design.

In which two categories, the organisms are divided on the basis of evolution ? How are the two categories different from each other ? [SAII – 2014]

Answer. On the basis of evolution, the organisms are divided into two categories :

(a) ‘Primitive’ or ‘lower’ organisms

(b) ‘Advanced’ or ‘higher’ organisms

Advanced organisms result from the gradual development of more complex organisms from the simpler ones /.eprimitive organisms.

 Why is it difficult to classify bacteria ? Give two reasons. [SAII -2014]

Answer. It is difficult to classify bacteria because :

(i) These organisms do not have a well defined nucleus or organelles and do not have multicellular body designs.

(ii) Mode of nutrition of these organisms can be either autotrophic or heterotrophic.

What are species ? State in terms of (1) hierarchy of classifications and (2) in relation to reproduction. [SAII -2014]

Answer.

1. Hierarchy of classification: Species is the lowermost category in the hierarchy of classification of groups of organisms.

2. In relation to reproduction : A species includes all organisms that are similar enough to breed and perpetuate.

What are Cryptogams ? Why are they called so ?

Answer. Thallophytes, Bryophytes and Pteridophytes are classified as Cryptogams as they have hidden reproductive organs.

We start classification of plants on the basis of differentiation of the plant body.

(i) Which division lacks a well differentiated body design ?

(ii). Where are such plants predominantly found ? [SAII -2014]

Answer.

(i) Thallophyta

(ii)These plants are predominantly found in aquatic habitat.

What is meant by warm-blooded and cold-blooded animals ? Explain. [SAII – 2014]

Answer. Warm-blooded animals have a relatively higher blood temperature and can maintain the constant  internal body temperature through metabolic processes. Mammals and birds are warm-blooded animals.

Cold-blooded animals like reptiles, amphibians and fish continuously change their body temperature

with change in the temperature of the environment.

Write the type of body cavity and symmetry possessed by nematodes. [SAII-2014]

Answer. Body cavity: Pseudocoelom.

Symmetry: Bilateral.

On what basis are plants and animals put into different categories ?

Answer. Plants and animals are put into different categories on the basis of their ability to make their own food. Being able to produce one’s own food versus having to get food from outside would make very different body designs necessary.

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

Answer. Yes, advanced organisms are the same as complex organisms because there is a possibility that complexity in design will increase over evolutionary time. Thus, it may not be wrong to say that ‘older’ (‘primitive’ or ‘lower’) organisms are simpler while ‘younger’ (‘advanced’ or ‘higher’) organisms are more complex.

 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? [SAII – 2011]

Answer. The grouping having the smallest number of organisms with a maximum of characteristics in ; common is the ‘species’. While the group having the largest number of organisms with a maximum of characteristics in common is the ‘kingdom’. 

Explain the basis for grouping organisms into five kingdoms.[SAII – 2011]

Answer. The basis for grouping organisms into five kingdoms depends on their:

(a) Cell structure.

(b) Mode and source of nutrition.

(c) Body organization.

classify the following organisms into their respective kingdoms as per Whittaker’s five kingdom classification:

Amoeba, Euglena, Birds, Herbs, Cats, Lactobacillus.

Answer. Amoeba — Protist Euglena — Protist

Birds — Animalia Herbs — Plantae

Cats — Animalia Lactobacillus — Monera

What is meant by the characteristics of an organism ? Mention two characteristics of class reptilia. [SAII- 2014]

Answer.

Characteristics of an organism are the features that help us in knowing, identifying and classifying the organism.

The two characteristics of class Reptilia are as follows :

1. These are cold-blooded animals.

2. They respire through lungs.

Diversity in Living Organisms class 9 biology long question:

State any two characteristics of mammalia. Name two egg laying mammals. [SAII – 2014]

Answer. Characteristics of mammalia :

1. Mammals are warm-blooded animals having hairs on their body.

2. They have four chambered hearts.

3. They have mammary glands for the production of milk to nourish their young ones

4. Skin has sweat or oil glands.
   Egg laying mammals: Platypus, Echidna.

xplain the following terms:

(i) Bilateral symmetry, (ii) Triploblastic animals and (iii) Open circulatory system.[SAII-2014]

Answer.

(i) Bilateral symmetry : It means that the left and right halves of the body have the same design. It is found in Platyhelminthes.

(ii) Triploblastic animals : In triploblastic animals, there are three layers of cells from which differentiated tissues can be made.

(iii) Open circulatory system : In an open circulatory system, blood does not flow in well defined blood vessels. Blood is pumped by a heart into the body cavities, where tissues are surrounded by the blood.

Give three examples of the range of variations that you see in life forms around you.

Answer. The following range of variations can be seen in different life forms which occur on Earth.

1. Variation in size: Some microscopic bacteria are few micrometer in size whereas blue whale
   and redwood trees of California are approximately 30 meters and 100 meters respectively.

2. Variation in lifespan : Some pine trees live for thousands of years while insects like mosquitoes die within a few days.

3. Variation in body colors: Some life forms such as worms are colorless or even transparent whereas many of the birds, insects, flowers etc., are brightly coloured.

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?

Answer. The more basic characteristic for classifying organisms is the kind of cells they are made of because:

(a) An eukaryotic cell has membrane-bound organelles, including a nucleus, which allow cellular processes to be carried out efficiently in isolation from each other.

(b) Further, nucleated cells would have the capacity to participate in making a multicellular organism because they can take up specialized functions. Therefore, this is a basic characteristic of classification.

Which organisms are called primitive and how are they different from the so-called advanced organisms ? [SAII – 2011]

Answer.

13 How are pteridophytes different from the phanerogams? [SAII-2011]

Answer.

Question.14 How do gymnosperms and angiosperms differ from each other ? [SAII -2011]

Answer.

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

Answer. The characteristics of body design used for classification of plants will be very different from those important for classifying animals. This is because the basic designs are different, based on the need to make their own food (plants) or acquire it (animals). Therefore, these design features (having a skeleton) are to be used to make subgroups, rather than making broad groups.

X, Y and Z are living organisms.

(a) Identify the group to which they belong on the basis of following features. .

(i) X — Microscopic, unicellular, prokaryotic.

(ii) Y — Microscopic, unicellular, eukaryotic, and shows locomotion with the help of pseudopodia/flagella.

(iii) Z — Multicellular, filamentous, eukaryotic, autotrophic and aquatic.

(b) Which amongst the above is most advanced ?

(c) Name one organism each belonging to the groups of X, Y and Z. [SAII-2014]

Answer.

(a) (i) Monera, (ii) Protista, (iii) Plantae (Thallophyta)

(b) Fungi are the most advanced organisms as compared to Protista and Monera.

(c) X — Bacteria

Y — Amoeba

Z —Spirogyra.

Give the appropriate term for each of the following:

(а) Complex sugar that makes the fungal cell wall.

(b) Plants which bear naked seeds.

(c) Blue-green algae.

(d) Basic unit of classification.

(e) Group of unicellular eukaryotic organisms. [SAII – 2014]

Answer.

(a) Chitin

(b) Gymnosperms

(c) Cyanobacteria

(d) Cell structure

(e) Protista.

(a) Why are angiosperms so called ? In which structures do the seeds develop ? Why are cotyledons considered an important part of seed ?

(b) Differentiate between the two categories of angiosperms giving an example of each. [SAII – 2014]

Answer.

(a) Angiosperms are so called because these plants have covered seeds.

Seeds develop within the ovary which later modify into fruit.

Cotyledons are considered an important part of seed as these are seed leaves. In many instances, they emerge and become green when the seed germinates.

(b) The angiosperms are divided into two categories depending upon the number of cotyledons present in the seeds:

(i) Monocot — Plants having single cotyledon, e.g., Paphiopedilum, maize.

(ii) Dicot — Plants having two cotyledons, e.g., Ipomoea, sunflower.

(a) Identify the organism shown in the picture and write the common name and scientific name of the organism.

(b) Name its phylum and kingdom.

(c) Which organ of the digestive system normally harbors this organism ?

Answer.

(a) It is Ascaris.Common name is Roundworm.Scientific name is Ascaris lumbricoides.

(b) Phylum — Nematoda and Kingdom-Animalia.

(c) Small intestine (an organ of the digestive system) normally harbors this organism.

(a) Identify three features possessed by all chordates.

(b) Name the classes of vertebrates which have the following characteristics:

(1) Animals that have streamlined bodies and gills for breathing.

(2) Animals that are found both on land and in water.

(3) Animals that have mammary glands for the production of milk to nourish their young ones.

Answer.

(a) Features of chordates:

• They have notochord.

• They have a dorsal hollow nerve cord.

• They are triploblastic.

• They have paired gill pouches.

• They are coelomates.

(b)

1. Pisces

2. Amphibians

3. Mammals.

Question.6 What is the criterion for classification of organisms as belonging to the kingdom Monera or Protista? [SAII – 2011]

Answer.Criterion for classification of organisms belonging to kingdom Monera:

(i) These organisms do not have a defined nucleus or organelles, nor do any of them show multicellular body designs.

(ii) Some of them have cell walls while some do not.

The mode of nutrition of organisms in this group can be either by synthesizing their own food (autotrophic) or getting it from the environment (heterotrophic).

(iv) This group includes bacteria, blue-green algae or cyanobacteria and mycoplasma.

Criterion for classification of organisms belonging to kingdom Protista:

(i) This group includes many kinds of unicellular eukaryotic organisms.

(ii) Some of these organisms use appendages, such as hair-like cilia or whip-like flagella for moving around.

(iii) Their mode of nutrition can be autotrophic or heterotrophic.

(iv) This group includes unicellular algae, diatoms and protozoans.

How do poriferan animals differ from coelenterate animals ? [SAII -2011]

Answer.

Question.8 How do annelid animals differ from arthropods ? [SAII -2014]

Answer.

Question.9 What are the differences between amphibians and reptiles ? [SAII – 2011]

Answer.

Question.10 What are the differences between animals belonging to the Aves group and those in the Mammalia

group ? [SAII- 2011]

Answer.

What are the major divisions in the plantae ? What is the basis for these divisions ? [SAII – 2014]

Answer.

The major divisions in the kingdom plantae are :

(i) Thallophyta (ii) Bryophyta

(iii) Pteridophyta (iv) Gymnosperms

(v) Angiosperms.

The basis of these divisions are :

(a) Whether the plant body has well differentiated, distinct components.

(b) Whether the differentiated plant body has special tissues for the transport of water and other substances within it.

(c) The ability to bear seeds.

(d) Whether the seeds are enclosed within fruits.