Question 1

Q1: Why are living organisms classified?

Accepted Answer

Living organisms are classified for the following reasons: 1.  Convenient Study: The vast diversity of life, with millions of species, makes it impossible to study each organism individually. Classification groups organisms into convenient categories (taxa) based on shared characteristics, making th...

Question 2

Q10: Illustrate the taxonomical hierarchy with suitable examples of a plant and an animal.

Accepted Answer

The taxonomical hierarchy is the arrangement of various taxonomic categories in descending order, from kingdom to species. As we move down the hierarchy, the number of common characteristics increases. Example of a Plant (Mango):    Kingdom: Plantae    Division: Angiospermae    Class: Dicotyledonae...

Question 3

Q2: Why are the classification systems changing every now and then?

Accepted Answer

Classification systems are dynamic and change over time because our understanding of organisms and their interrelationships is constantly improving. The factors contributing to these changes are: 1.  New Discoveries: As new species are discovered, they need to be placed appropriately within the exis...

Question 4

Q3: What different criteria would you choose to classify people that you meet often?

Accepted Answer

To classify people I meet often, I could use various criteria based on easily observable characters, similar to the principles of taxonomy. The choice of criteria would depend on the purpose of the classification. Some possible criteria are: 1.  Relationship: Grouping them as family, friends, collea...

Question 5

Q4: What do we learn from identification of individuals and populations?

Accepted Answer

From the identification of individuals, we learn the specific identity of an organism. Identification is the process of determining the correct name and placement of an organism within the established system of classification. This allows us to know its species, genus, family, and other taxonomic ra...

Question 6

Q5: Given below is the scientific name of Mango. Identify the correctly written name. Mangifera Indica Mangifera indica

Accepted Answer

The correctly written scientific name of Mango is Mangifera indica. This is based on the universally accepted rules of binomial nomenclature: 1.  The first word represents the genus and starts with a capital letter (e.g., Mangifera). 2.  The second word represents the specific epithet and starts wit...

Question 7

Q6: Define a taxon. Give some examples of taxa at different hierarchical levels.

Accepted Answer

A taxon (plural: taxa) is the scientific term for any unit or category in the system of biological classification. It represents a group of one or more organisms that are considered to form a unit at a particular level in the taxonomic hierarchy. Each taxon represents a rank in classification. Examp...

Question 8

Q7: Can you identify the correct sequence of taxonomical categories? (a) Species → Order → Phylum → Kingdom (b) Genus → Species → Order → Kingdom (c) Spec...

Accepted Answer

The correct sequence of taxonomical categories in ascending order is: (a) Species → Order → Phylum → Kingdom Explanation: The taxonomic hierarchy is an arrangement of categories in a definite sequence from lower to higher ranks. The standard ascending order is: Species → Genus → Family → Order → Cla...

Question 9

Q8: Try to collect all the currently accepted meanings for the word 'species'. Discuss with your teacher the meaning of species in case of higher plants a...

Accepted Answer

The term 'species' is a fundamental unit of classification. Two currently accepted meanings are: 1.  Morphological Species Concept: This defines a species as a group of individual organisms with fundamental morphological similarities. Based on distinct observable structural differences, one can dist...

Question 10

Q9: Define and understand the following terms: (i) Phylum (ii) Class (iii) Family (iv) Order (v) Genus

Accepted Answer

(i) Phylum: Phylum is a taxonomic category placed below Kingdom and above Class. It consists of related classes sharing common fundamental features. For example, Phylum Chordata includes classes like Amphibia, Reptilia, and Mammalia, all of which share features like the presence of a notochord and a...

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