Class 9 Science Chapter 2 Classification of Organisms Notes

1. Short answer type questions.

a. What is classification ? On what basis are living  organisms classified?

= Organizing all the living organism into groups and on the basis of similar dissimilar characteristics is called classification of  living beings. Living Organisms are classified on the basis of similar a dissimilar characteristics.

b. What is taxonomy?

= The science of naming describing and classifying organisms is called taxonomy.

c. Who developed the system for naming living organisms?

= Carolus Linnaeus developed the system for naming living organisms.

d. What are the seven classification groups?

= i. King doom

ii. Phylum

iii. Order

iv. Class

v. Family

vi. Species

vii. Genus

e. Who is known as the father of taxonomy?

→ Carolus Linnaeus is known as the bather of taxonomy.

f. What is binomial nomenclature?

= The system of assigning the scientific name to living organisms in two Latin words, first name generic name and second specific name is. called binomial nomenclature.

2. Long answer type questions:

a. Who proposed the five-kingdom classification? On what basis is this classification proposed? Explain.

= Robert H. Whitaker proposed the five kingdom classification.

- The classification proposed on the basis of the following criteria:

i. Complexity of cell: Prokaryotic cells, Eukaryotic cells 

ii. Lifesyles: Decomposers, Consumers

iii. Body organization: Unicellular organisms, Multicellular organisms

iv. Phylogenetic relationship of organisms: Monera, Protista

v. Mode of nutrition: Autotrophs, Hererotrophs

vi. Fungi: Plantae, Animalia

b Write the scientific name of mango, dog tiger, pea, wheat and mustard?

= Mango ----------- Mangifera indica

Dog ----------------- Canis familiaris

Tiger ---------------- Panthera tigris

Cow ----------------- Bos taurus

Pea ------------------ Pisum sativum

Wheat --------------- Triticum aestivum

Mustard ------------ Brassica campestris

c. Write about the merits of five kingdom classification.

= The merits of the kingdom classification are:

i. It separates unicellular eukaryotic organisms from multicellular eukaryotic organisms.

ii. This system has separated con photosynthesic Fungi from the photosynthesic green plants.

iii. The Five-kingdom classification is based on the phylogenetic relationship of the organisms which reflect the phylogency of different lifestyles.

iv. This system is based upon the mode of obtaining nutrition, so it demarks the multicellulars organisms into three kingdoms (plantae, fungs and animalia) based the modes of nutrition.

d. Where do archaeabacteria typcally live? Explain.

= Archaeabacteria typically live in harsh environment. Their types are

i. Halophiles can survive in the highly salty environments. Example, Halobacterium, Halococcus, etc.

ii. Methanogens can thrive in marshy places and produce methane during metabolic activities. They are anaerobic autotrophs. Example, Methanococcus.

iii. Thermoacidophiles live in hat and acidic environment such as hot sulphur springs and sulfataric ervironments within deep sea vents or in other environments of geothermal activity.

e. List the general features that characterize protista?

= The general features that characterize protita are:

i. The protistians have membrare bound cell organelles like mitochondria, endoplasmic reticulum, ribosone, etc.

ii. They are primitive eukaryotic as they have a true nucleus.

iii. They usually hear flagella, cilia or pseudopodia locomotory organs fox locomotion.

iv. Thing reproduce by both asexual and sexual methods.

v. They don't exhibit cellular differentiation, hence tissue system is absent.

f. Write the importance of classification.

= The importance of classification are:

i. It makes the study of wide variety of organisms easy and in a systematic manner.

ii. It helps to understand how different organisms have evolved with time.

iii. It helps to understand the inter-relationships among different organisms.

iv. It forms a base for the study of other biological science, like biogeography.

v. It also forms the basis for giving scientific names to the living organisms. This helps to universalize their names so that people around the world can recognize the organism irrespective of their local.

g. Enlist the characteristics of the kingdom monera.

= The characteristics of the kingdom monera are:

i. They are unicellular, microscopic prokaryotic organisms.

ii. They have incipient nucleus which is represented by coiled naked double stranded deoxyriko nucleic acid (DNA).

iii. The membrane bound cell organelles like mitochondria, Golgi complex, etc. are absent.

iv. Generally, they have a rigid cell wall.

v. Their modes of nutrition are autotrophic, parasitic are symbiotic and saprotrophic.

h. Why is it it necessary to classify living organism? Give reason.

= It is necessary to classify living organism because it helps in the identification of living organisms and in understanding the diversities at organisms by helping to learn more about them easily and practically.

i. What is scientific name of an organism and how is it written?

= Scientific name is the internationally identified name combined using genus and species. It is formed by combining genus and species. At first the genus particular organisms is written and then species of same organisms is written. The first letter of should be in upper case, and rest all, let it bein lower case.

j. What kinds of organisms are grouped under Protista? Would you consider 0this kingdom a natural one?

= The Organisms which have the membrane bound cell oragnelles like mitochondria, endoplasmic reticulum ribosome, etc have a true nucleus and reproduce by both asexual and sexual method, etc are grouped under protista. Yes, I would consider this kingdom a natural one.

k. Illustare the taxonomical hierarchy with suitable example of a plant and an animal.

= Taxonomial hierarchy is the arrangement of categories by providing the back to each category Species, genus, family, order, class, phylum and kingdom represent the seven categories in the hierarchy. The category or rank is the unit of classification. The taxonomic category which has the lowest rank (species) is placed at the bottom of the hierarchy and the one with the highest rank (kingdom) is placed at the top at the hierarchy. Examples: housefly (musca domestica) belongs to genus and wheat (Triticum aestivam) belongs to genus that belongs to Family that belongs to order.

l. Which kingdom do the Following organisms belong to?

= Mucor = Fungi

Mushroom = Fungi

Nostoc = Monera

Mustard = Plantae

Pea = Plantae

Paramecium = Protista

Azotobacter = Monera.

Euglena = Protista

Plasmodium = Protista

Yeast = Fungi

m. How do Fungi digest their food?

= Fungi digest their food externally by some secreting enzymes onto the Food and then absorbing the soluble and similar nutrients that result from digestion.

3. Give reasons:

a. The five kingdom classification is more advantagenous than the two-kingdom classification.

= Because It have wider field to classify organisms and this system classify animals on the basis of complexity of cell, body organization, mode of nutrition, lifestyles.

b. Classification of human beings is essential.

= Because its helps in identification of living organisms and in understanding the diversities of organisms by helping to learn more about them easily and practically.

c. The protistans are more advanced than the moneras.

= Because protistians contains eukaryotic cells whereas Moneras contains prokaryotic cells.

d. Mushroom is a saprophytic fungus.

= Because this fungi derives their food from dead and decayed organic matter.

e. We classify organisms.

= Because it makes us easy to /study about different organisms.