CLASS ELEVEN BIOLOGY CHAPTER 1 DIVERSITY IN THE LIVING WORLD QUESTIONNAIRE FOR TESTS AND REVISION.

It can be used as reference material for competitive exams also.

Q1. The no. Species that are known and describe range between?

Ans. 1.7- 1.8 billion

Q2. Define biodiversity.

Ans. The number and types of organisms present on earth.

Q3.  Define nomenclature.

Ans. The naming of living organisms

Q4. Define identification.

Ans. Describing an organism.

Q5. What is the significance of giving scientific names?

Ans.  The scientific names ensure that each organism has only one name. Description of any organism should enable the people (in any part of the world) to arrive at the same name. They also ensure that such a name has not been used for any other known organism.

Q6. What system of naming organisms uses a two-part format?

Ans. Binomial nomenclature

Q7. What are the two components of a scientific name?

Ans. Generic name and the specific epithet.

Q8. Who is credited with developing binomial nomenclature?

Ans. Carolus Linnaeus

Q9. Why is binomial nomenclature preferred over common names?

Ans. Binomial names are universal and avoid confusion caused by different languages having different common names for the same organism.

Q10. How many parts does a scientific name according to binomial nomenclature have?

Ans. Two

Q11. What is the first part of a scientific name called?

Ans. Genus

Q12. How is the genus part of a scientific name typically written?

Ans. With a capital letter

Q13. What is the second part of a scientific name called?

Ans. Species epithet

Q14. How is the species epithet of a scientific name typically written?

Ans. With a lowercase letter

Q15. In what language are scientific names according to binomial nomenclature written?

Ans. Latin (or latinized)

Q16. How are scientific names written?

Ans. Italicized when printed, underlined when handwritten

Q17. What does the scientific name Mangifera indica tell us about a mango?

Ans. Mangifera is the genus, indicating the broader group the mango belongs to. Indica is the specific epithet, potentially referring to a specific characteristic or geographic origin of this particular mango species.

Q18. What additional information can be included after the species epithet in a scientific name?

Ans. The name of the author who first described the species, written in a standardized abbreviated form. (e.g., Mangifera indica linn. Indicates Linnaeus first described this mango species)

Q19. Who is known as the ‘The Darwin of the 20th century’?

Ans. ERNST MAYR

Q20. What is classification?

Ans. Classification is the process by which anything is grouped into convenient categories based on some easily observable characters.

Q21. Why is classification important in biology?

Ans. Because it's nearly impossible to study every organism individually, classification allows us to:

• Organize living things into manageable groups based on shared characteristics.
• Make comparisons between organisms within and across groups.
• Develop a framework for understanding the relationships and diversity of life.

Q22. What is the basic unit of classification?

Ans. Taxa (singular: taxon) - these are categories used to group organisms.

Q23. Can taxa encompass different levels of classification?

Ans. Yes. "plants" and "wheat" are both taxa, but "plants" represents a broader category than "wheat." this demonstrates hierarchical classification, where groups are nested within larger groups.

Q24. How does hierarchical classification work?

Ans. Taxa at different levels have a nested relationship. For example, "dogs" are a type of "mammal," which is a type of "animal." each level represents a more specific grouping based on shared characteristics.

Example:

• Thinking of "dogs" conjures an image of a specific animal within the broader category of "mammals."
• Similarly, "mammals" refer to animals with fur or hair and mammary glands, a more specific group within "animals."

Q25. What does this hierarchical structure tell us about the relationships between organisms?

Ans. It suggests that organisms within a smaller taxon share more recent common ancestors with each other compared to those in a broader taxon. This reflects the evolutionary history of life.

Q26. What process assigns living things to groups based on shared characteristics?

Ans. Classification

Q27. What is the scientific study of classifying organisms called?

Ans. Taxonomy

Q28. What information do taxonomists consider when classifying organisms today?

Ans. External and internal structures, cellular structure, development processes, and ecological information.

Q29. How does modern taxonomy differ from earlier classification methods?

Ans. Modern taxonomy goes beyond simple "use" and considers a broader range of biological data to establish evolutionary relationships.

Q30. What are the four fundamental processes of taxonomy?

Ans. Characterization, identification, classification, and nomenclature.

Q31. Why were early classifications of organisms likely developed?

Ans. To identify sources for basic needs like food, clothing, and shelter.

Q32. What principle formed the basis of these early classifications?

Ans. The "use" of the organism for human needs.

Q33. What are some limitations of using "use" as the sole criterion for classifying organisms?

Ans. It doesn't reflect evolutionary relationships, may group unrelated organisms based on similar uses, and ignores organisms with no direct human use.

Q34. How did the focus of classification change over time?

Ans. From a focus on immediate human use to a more scientific understanding of biological relationships and shared characteristics.

Q35. What advancements allowed for more sophisticated classification systems?

Ans. Developments in microscopy, cell biology, and evolutionary theory provided a deeper understanding of organismal structures and relationships.

Q36. How does modern taxonomy contribute to our understanding of the natural world?

Ans. By organizing life forms, studying their relationships, and providing a framework for further biological research and conservation efforts.

Q37. What field of study focuses on understanding the diversity of organisms and their relationships?

Ans. Systematics

Q38. What is the etymology of the word "systematics"?

Ans. Derived from the Latin word "systema," meaning systematic arrangement.

Q39. What famous publication by Carolus Linnaeus exemplifies the systematic approach?

Ans. Systema naturae

Q40. Beyond understanding relationships, what other tasks does modern systematics encompass?

Ans. Identification, nomenclature (naming), and classification.

Q41. How does the scope of systematics differ from earlier classification methods?

Ans. Modern systematics goes beyond simple grouping and actively investigates evolutionary relationships.

Q42. What critical aspect sets systematics apart from basic classification?

Ans. Its emphasis on understanding the evolutionary relationships between organisms.

Q43. How does systematics determine these evolutionary relationships?

Ans. By analysing various data points, including morphology (physical structure), development processes, and genetic information.

Q44. Why is understanding evolutionary relationships important in systematics?

Ans. It allows for a more natural and accurate grouping of organisms based on their shared ancestry and evolutionary history.

Q45. How does systematics contribute to other biological disciplines?

Ans. By providing a framework for understanding biodiversity, ecology, and conservation efforts.

Q46. How have advancements in technology impacted the field of systematics?

Ans. Technological developments in DNA analysis and molecular biology have revolutionized our understanding of evolutionary relationships and refined systematic classification.

Q47. What is the process of classifying organisms into a series of nested groups called?

Ans. Taxonomic classification

Q48. Why is taxonomic classification not a one-step process?

Ans. It involves a hierarchy of ranks or categories, progressively grouping organisms based on shared characteristics.

Q49. What is a taxonomic category?

Ans. A level within the classification system, representing a rank for grouping organisms. (e.g., insects, mammals)

Q50. What is the plural form of taxon?

Ans. Taxa

Q51. How does the example of insects illustrate the concept of taxonomic categories?

Ans. Insects share common features (three pairs of jointed legs) and represent a recognizable group assigned a specific rank within the hierarchy.

Q52. What differentiates taxonomic categories from simple morphological groupings?

Ans. Taxonomic categories represent distinct biological entities with shared evolutionary history, not just superficial similarities.

Q53. What are some common taxonomic categories established through studies of known organisms?

Ans. Kingdom, phylum/division (plants), class, order, family, genus, and species.

Q54. What is the lowest taxonomic category for all organisms, including plants and animals?

Ans. Species

Q55. What is the fundamental requirement for placing an organism within various taxonomic categories?

Ans. Knowledge of its characteristics to identify similarities and differences with other organisms.

Q56. How does comparing characteristics of individuals and groups of organism aid classification?

Ans. By analyzing similarities and dissimilarities, we can determine how closely related organisms are and group them accordingly within the taxonomic hierarchy.

Q57. Define taxonomic hierarchy.

Ans. The taxonomic hierarchy is a ranking system used in biology to classify organisms into increasingly specific groups based on their shared characteristics. It's like a nested set of boxes, where broader categories hold smaller, more defined ones.

Q58. What is the significance of taxonomic hierarchy?

Ans.   organization: provides a structured framework for understanding the diversity of life.

          relationships: helps understand evolutionary relationships between organisms.

         communication: enables scientists to communicate precisely about different organisms using a standardized system.

Q59. Give an example of taxonomic hierarchy.

Ans. Example:

• kingdom: animalia (animals)

phylum: chordata (organisms with a backbone)

class: mammalia (hairy animals with mammary glands)

order: carnivora (meat-eating mammals)

family: canidae (dog family)

genus: canis (wolves, dogs, coyotes)

Species: canis familiaris (domestic dog)

Q60. In taxonomic studies, what fundamental characteristic unites a group of individual organisms?

Ans. Shared morphological similarities (observable physical characteristics)

Q61. How do taxonomists distinguish between closely related species?

Ans. By identifying distinct morphological differences between them.

Q62. In a scientific name like Mangifera indica, what does the second word (indica) represent?

Ans. The specific epithet, referring to a particular species within the genus.

Q63. What taxonomic level does the first word in a scientific name (e.g., Mangifera) represent?

Ans. Genus, a higher- level category grouping related species.

Q64. Can a genus contain only one species?

Ans. No, a genus can have one or more species but with shared morphological similarities.

Q65. Provide an example of a genus with multiple species.

Ans. Panthera, which includes species like Panthera leo (lion) and Panthera tigris (tiger).

Q66. How does the scientific name solanum nigrum illustrate multiple species within a genus?

Ans. Solanum is the genus, and nigrum is the specific epithet for a distinct species within that genus (likely referring to a specific type of nightshade plant).

Q67. What is the scientific name for humans, and how does it follow the species and genus naming convention?

Ans. Homo sapiens. Homo is the genus (referring to humans in general), and sapiens is the specific epithet for our species.

Q68. Besides morphological characteristics, what other factors might be considered when distinguishing between species?

Ans. Modern taxonomy may also consider factors like reproductive compatibility, genetic information, and ecological niche.

Q69. How does the concept of species play a crucial role in biological studies?

Ans. Species are the fundamental unit of biodiversity, serving as a reference point for understanding evolution, ecology, and conservation efforts.

Q70. What is a genus in taxonomic classification?

Ans. A group of closely related species sharing more characteristics with each other than with species in other genera.

Q71. How can you describe the relationship between species within a genus?

Ans. They are considered aggregates of closely related species with a significant number of shared features.

Q72. How does the example of potato (solanum tuberosum) and brinjal (solanum melongena) illustrate a shared genus?

Ans. Both belong to the genus solanum, indicating they share more characteristics with each other than with species in other genera.

Q73. What big cats belong to the genus panthera, and what does this suggest about their relationships?

Ans. Lion (Panthera leo), leopard (Panthera pardus), and tiger (Panthera tigris) all belong to panthera. This suggests they share a closer evolutionary relationship compared to cats in other genera.

Q74. How does the distinction between panthera (lions, tigers) and felis (cats) demonstrate the concept of genus?

Ans. Panthera species share more characteristics with each other than with felis cats, highlighting the importance of shared features within a genus.

Q75. What kind of characteristics are typically shared by species within a genus?

Ans. These can be morphological (physical features), behavioural, physiological (body functions), or genetic.

Q76. How does the concept of a genus help us organize the diversity of life?

Ans. By grouping related species based on shared characteristics, genera provide a hierarchical level within the taxonomic classification system.

Q77. Are there any limitations to using a genus as the sole indicator of relationships between organisms?

Ans. While a genus suggests a close relationship, further investigation may reveal even closer relationships within the genus or with species in other genera.

Q78. What taxonomic category encompasses a group of related genera?

Ans. Family

Q79. How does the level of shared characteristics within a family compare to a genus or species?

Ans. Families exhibit fewer shared similarities compared to species or genus.

Q80. What criteria are typically used to classify plant families?

Ans. A combination of vegetative (non-reproductive) and reproductive features.

Q81. How do the genera solanum (potato, brinjal), petunia, and datura illustrate the concept of a plant family?

Ans. Despite being separate genera, they are placed within the solanaceae family due to shared characteristics, suggesting a closer relationship than to plants in other families.

Q82. How does the classification of panthera (lions, tigers) and felis (cats) within the felidae family demonstrate the family level?

Ans. Although distinct genera, they are grouped in felidae because they share more characteristics with each other than with animals in other families.

Q83. How can comparing a cat and a dog highlight the role of families in classification?

Ans. While sharing some similarities, their placement in separate families (felidae and canidae) reflects a significant difference in their overall characteristics.

Q84. What types of characteristics might be considered when grouping organisms into families?

Ans. These can include physical features (morphology), behaviour, physiology (body functions), and even some genetic similarities.

Q85. How does the family level contribute to the organization of life's diversity?

Ans. Families provide a broader level of classification, grouping related genera based on shared characteristics, offering a more comprehensive view of evolutionary relationships.

Q86. What taxonomic category encompasses a group of related families?

Ans. Order

Q87. How does the level of shared characteristics within an order compare to a family or genus?

Ans. Orders exhibit even fewer shared similarities compared to families or genera.

Q88. How are plant orders like convolvulaceae (morning glory family) and solanaceae (nightshade family) typically identified?

Ans. Primarily based on shared floral characteristics, suggesting a closer relationship than to plants in other orders.

Q89. How does the animal order carnivora (meat-eaters) exemplify the concept of order?

Ans. Families like felidae (cats) and canidae (dogs) are grouped within carnivora due to shared characteristics related to diet and anatomy, despite being distinct families.

Q90. What taxonomic level encompasses related orders?

Ans. Class

Q91. How does the example of order primata (primates) and order carnivora (carnivores) illustrate the class level?

Ans. Although separate orders, both belong to the class mammalia because they share more characteristics with each other than with animals in other classes.

Q92. Can a class include multiple orders?

Ans. Yes, a class can encompass several related orders based on shared features.

Q93. What taxonomic category groups classes of animals with similar characteristics?

Ans. Phylum (the term "division" is used for plants)

Q94. What features might unite various animal classes like fish, amphibians, reptiles, birds, and mammals into the phylum chordata?

Ans. The presence of a notochord (flexible rod) and a dorsal hollow neural system (arrangement of nerves) are examples of common features in this phylum.

Q95. How does the distinction between phylum and class highlight the decreasing number of shared characteristics at higher taxonomic ranks?

Ans. Classes within a phylum share more specific similarities than all the classes combined do within the phylum.

Q96. What is the highest taxonomic category in the classification system for animals?

Ans. Kingdom animalia

Q97. What kingdom encompasses all plant life within the classification system?

Ans. Kingdom plantae

Q98. How does the number of shared characteristics change as we move up the taxonomic hierarchy?

Ans. The number of common characteristics decreases as we move from lower taxa (species) to higher categories (kingdom).

Q99. Why does the problem of classification become more complex at higher taxonomic levels?

Ans. With fewer shared characteristics, determining relationships between organisms within the same high-level category becomes more challenging.

Q100. What is the purpose of subcategories within the taxonomic hierarchy?

Ans. Subcategories provide a more refined level of classification to accommodate the vast diversity of life and ensure a more accurate placement of various taxa.

Q101. Besides the decreasing number of shared characteristics, are there any other challenges faced in classifying organisms at higher taxonomic ranks?

Ans. Convergent evolution (unrelated organisms developing similar traits) can make it difficult to determine true evolutionary relationships at these levels.

Q102.  How do advancements in technologies like DNA analysis contribute to improving classification, especially at higher taxonomic levels?

Ans. By analyzing genetic information, scientists can gain deeper insights into evolutionary relationships and refine the taxonomic hierarchy to reflect a more accurate understanding of life's diversity.