Biological Classification – Summary - NEET Biology MCQs (Part 13)

Correct Answer: B

Aristotle was one of the earliest scientists to attempt a biological classification of living organisms. He classified plants and animals based on simple morphological characters. For example, he divided animals into those with red blood and those without red blood. His work laid the foundation for later developments in biological classification.

Correct Answer: C

Carolus Linnaeus proposed the two-kingdom system of classification in which all living organisms were placed into two main groups: Plantae and Animalia. Plants included organisms capable of photosynthesis, while animals included heterotrophic organisms that depended on plants or other animals for food. This system was widely used for a long time before more advanced classification systems were developed.

Correct Answer: C

R.H. Whittaker proposed the five kingdom classification system in 1969. In this system, all living organisms were grouped into five kingdoms: Monera, Protista, Fungi, Plantae and Animalia. This classification was based on important criteria such as cell structure, body organisation, mode of nutrition, reproduction and evolutionary relationships.

Correct Answer: A

R.H. Whittaker proposed the five kingdom classification based on several important biological criteria. These include the type of cell structure (prokaryotic or eukaryotic), the level of body organisation (unicellular or multicellular), the mode of nutrition (autotrophic or heterotrophic), methods of reproduction and the evolutionary or phylogenetic relationships among organisms. These criteria helped create a more scientific and natural classification system.

Correct Answer: C

In the five kingdom classification proposed by R.H. Whittaker, all prokaryotic organisms are placed in Kingdom Monera. Bacteria are prokaryotic organisms that lack a true nucleus and membrane-bound organelles. Because of these characteristics, they are classified under Kingdom Monera in this system.

Correct Answer: B

Bacteria are called cosmopolitan in distribution because they occur almost everywhere in nature. They can be found in soil, water, air, inside living organisms and even in extreme environments such as hot springs, deserts and deep oceans. Their ability to survive in a wide range of habitats makes them one of the most widely distributed organisms on Earth.

Correct Answer: C

Bacteria show the greatest metabolic diversity among all living organisms. They can obtain energy and nutrients in many different ways. Some bacteria are autotrophic and produce their own food through photosynthesis or chemosynthesis, while others are heterotrophic and obtain nutrients from organic matter. Because of this wide range of metabolic processes, bacteria can survive in many different environments.

Correct Answer: A

Bacteria show great metabolic diversity in their mode of nutrition. Some bacteria are autotrophic, meaning they can synthesize their own food from inorganic substances using light or chemical energy. Others are heterotrophic and depend on organic matter or living organisms for their nutrition. Because of these different nutritional strategies, bacteria can survive in many diverse environments.

Correct Answer: A

Kingdom Protista includes mostly single-celled eukaryotic organisms. These organisms have a true nucleus and membrane-bound organelles. Major groups included in Protista are Chrysophytes, Dinoflagellates, Euglenoids, Slime moulds and Protozoans. Many of them live in aquatic environments and show diverse modes of nutrition and reproduction.

Correct Answer: B

Protists are eukaryotic organisms, meaning their cells contain a well-defined nucleus and membrane-bound organelles such as mitochondria, endoplasmic reticulum and Golgi bodies. This distinguishes them from prokaryotic organisms like bacteria, which lack a true nucleus and membrane-bound organelles.

Correct Answer: C

Protists show a wide variety of reproductive methods. Many protists reproduce asexually through processes such as binary fission, budding or spore formation. Some protists are also capable of sexual reproduction, which involves the fusion of gametes or cell fusion followed by the formation of a zygote. This flexibility in reproduction helps them adapt to different environmental conditions.

Correct Answer: A

Fungi show a wide diversity in both structure and habitat. Some fungi are unicellular like yeast, while most are multicellular and filamentous with hyphae forming a mycelium. They can be found in many environments such as soil, water, air, decaying organic matter and even as parasites on plants and animals.

Correct Answer: B

Most fungi follow a saprophytic mode of nutrition. In this mode, fungi obtain nutrients from dead and decaying organic matter. They release enzymes onto the substrate, break down complex substances into simpler forms and absorb the dissolved nutrients. Because of this ability, fungi play a very important role as decomposers in ecosystems.

Correct Answer: C

Fungi show both asexual and sexual modes of reproduction. Asexual reproduction commonly occurs through spores such as conidia, sporangiospores or zoospores, and also by vegetative methods like fragmentation, fission and budding. Sexual reproduction occurs through the formation of spores such as oospores, ascospores and basidiospores, depending on the group of fungi.

Correct Answer: C

Kingdom Fungi is divided into four major classes based on the morphology of the mycelium, mode of spore formation and type of fruiting bodies. These four classes are Phycomycetes, Ascomycetes, Basidiomycetes and Deuteromycetes. Each class has distinct structural and reproductive characteristics.

Correct Answer: B

Kingdom Plantae includes all eukaryotic organisms that contain chlorophyll. Because of chlorophyll, these organisms can perform photosynthesis and produce their own food using sunlight, carbon dioxide and water. Plants are therefore autotrophic and play an important role as primary producers in ecosystems.

Correct Answer: A

Kingdom Plantae includes a wide variety of photosynthetic organisms. The major groups of plants included in this kingdom are algae, bryophytes, pteridophytes, gymnosperms and angiosperms. These groups show increasing complexity in structure and reproduction, from simple algae to highly developed flowering plants.

Correct Answer: A

The life cycle of plants exhibits alternation of generations. This means two phases alternate with each other: the haploid gametophytic generation and the diploid sporophytic generation. The gametophyte produces gametes, while the sporophyte produces spores. These two stages occur alternately in the life cycle of plants.

Correct Answer: B

Kingdom Animalia includes organisms that are heterotrophic, eukaryotic and multicellular. Their cells do not have a cell wall, which distinguishes them from plants and fungi. Animals obtain their food by consuming other organisms and usually show locomotion, well-developed sensory organs and complex body organization.

Correct Answer: C

Animals follow a holozoic mode of nutrition. In this type of nutrition, organisms ingest solid food, digest it internally and absorb the nutrients. Because animals cannot produce their own food like plants, they depend on other organisms for nutrition.

Correct Answer: B

Most animals reproduce by sexual reproduction. In this process, male and female gametes fuse during fertilization to form a zygote. The zygote then undergoes embryological development and grows into a new individual. Sexual reproduction helps produce genetic variation among offspring.

Correct Answer: A

Acellular organisms are entities that do not have a cellular structure. Viruses and viroids are examples of such organisms because they lack true cells and cannot carry out metabolic activities independently. They become active only when they infect a host cell. Because of this, they are not included in the five kingdom classification system.

Correct Answer: A

The five kingdom classification system proposed by R.H. Whittaker includes Monera, Protista, Fungi, Plantae and Animalia. However, some acellular organisms such as viruses and viroids are not included because they lack cellular organization. Lichens are also not placed in a separate kingdom because they are symbiotic associations of algae and fungi rather than independent organisms.