Patterns in Life Diversity and Classification Class 9 Extra Questions and Answer Science Chapter 12

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Class 9 Science Chapter 12 Patterns in Life Diversity and Classification Extra Questions

Class 9 Science Chapter 12 Extra Questions on Patterns in Life Diversity and Classification

Patterns in Life Diversity and Classification Class 9 Very Short Question Answer

Question 1.
Define endemic species.
Answer:
Species found only in a particular region and do not occur naturally anywhere else are called endemic species.

Question 2.
Name two biodiversity hotspots in India.
Answer:
Western Ghats and Indo-Burma (North East India).

Question 3.
Give one example of an endemic animal of India.
Answer:
Nilgiri tahr.

Question 4.
What is biodiversity?
Answer:
The immense variety of living organisms on Earth is called biodiversity.

Question 5.
Name the endemic plant variety of India known as the Indian pitcher plant.
Answer:
Nepenthes khasiana.

Question 6.
Who proposed the five kingdom classification?
Answer:
Robert H. Whittaker (1969).

Question 7.
Name the five kingdoms in Whittaker’s classification.
Answer:
Monera, Protista, Fungi, Plantae and Animalia.

Question 8.
What is the cell wall of fungi made oj?
Answer:
Chitin.

Question 9.
Give one example of a saprophytic fungus.
Answer:
Mushroom.

Question 10.
Name one useful bacterium.
Answer:
Lactobacillus (used in making curd) or Rhizobium (fixes atmospheric nitrogen).

Question 11.
What is the term given to bryophytes in relation to the plant kingdom?
Answer:
Amphibians of the plant kingdom.

Question 12.
Name the vascular tissues found in pteridophytes.
Answer:
Xylem (for water transport) and phloem (for food transport).

Question 13.
Give one example of a gymnosperm.
Answer:
Pine (or cycad).

Question 14.
What is a thallus?
Answer:
A thallus is a simple, undifferentiated plant body without true roots, stems or leaves, found in thallophytes.

Question 15.
Which is the most diverse plant group on Earth?
Ans:
Angiosperms (flowering plants).

Question 16.
What is a notochord?
Answer:
A notochord is a flexible, rod-shaped structure that provides internal body support in chordates.

Question 17.
Name the phylum to which sponges belong.
Answer:
Porifera.

Question 18.
Which phylum shows the first appearance of bilateral symmetry?
Answer:
Platyhelminthes (flatworms).

Question 19.
Give one example of an echinoderm.
Answer:
Starfish (or sea urchin).

Question 20.
What type of skeleton do arthropods have?
Answer:
Exoskeleton (hard external skeleton).

Question 21.
Who introduced the binomial system of nomenclature?
Answer:
Carolus Linnaeus.

Question 22.
Write the scientific name of the tiger.
Answer:
Panthera tigris.

Question 23.
What does the first word in a scientific name represent?
Answer:
Name of the genus.

Question 24.
In what language are scientific names written?
Answer:
Latin or a Latinised form.

Question 25.
Write the correct hierarchy of classification from broadest to most specific.
Answer:
Kingdom → Phylum/Division → Class → Order → Family → Genus → Species.

Patterns in Life Diversity and Classification Class 9 Short Question Answer

Question 1.
Why are biodiversity hotspots important? Give two examples from India.
Answer:
Biodiversity hotspots are regions with many endemic species that have undergone significant habitat loss. They are important for conservation because protecting them safeguards many unique species. Indian biodiversity hotspots include the Western Ghats and the Himalayans.

Question 2.
How does biodiversity support human life?
Answer:
Humans depend on biodiversity for food, shelter, medicines and livelihoods. Farmers use diverse crop varieties for food security. Algae produce oxygen, decomposers maintain soil fertility, and pollinators like bees and birds support food production.

Question 3.
Why were fungi separated from the kingdom Plantae?
Answer:
Fungi were separated from the kingdom Plantae because:

• They are heterotrophic and obtain nutrients by absorption from dead or decaying matter.
• Their cell wall is made up of chitin, not cellulose.

These differences in nutrition and cell wall composition made it necessary to place them in a separate kingdom (Fungi) under the five-kingdom classification.

Question 4.
Differentiate between prokaryotes and eukaryotes with one example each.
Answer:

Prokaryotes	Eukaryotes
1. Cells lack a nucleus and membrane bound organelles	1. Cells have a well defined nucleus and membrane bound organelles.
2. No membrane bound organelles.	2. Have membrane bound organelles like mitochondria.
3. Usually unicellular.	3. May be unicellular or multicellular.
4. Examples: Bacteria, cyanobacteria.	4. Examples: Amoeba, plants, animals, fungi.

Question 5.
Compare bryophytes and pteridophytes in terms of body structure and reproduction.
Answer:

Bryophytes	Pteridophytes
1. Lack true roots, stems and leaves.	Have true roots, stems and leaves,
2. No vascular tissues.	Have vascular tissues (xylem and phloem).
3. Small plants growing in moist places.	Larger plants, some grow into trees.
4. Examples: Moss, Marchantia.	Examples: Fem, Horsetail.

Question 6.
Why are gymnosperms well-adapted to cold and dry regions?
Answer:

1. Gymnosperms have needle-like or scale-like leaves that reduce water loss.
2. They produce seeds that protect the embryo and contain stored food.
3. They do not require water for fertilisation.

Question 7.
Differentiate between invertebrates and vertebrates.
Answer:

Invertebrates	Vertebrates
1. Notochord is absent.	Notochord is replaced by a vertebral column.
2. Generally smaller in size.	Can be large in size.
3. Skeleton may be absent or external.	Have an internal skeleton.
4. Examples: sponge, earthworm, crab.	Examples: fish, frog, bird, human.

Question 8.
What is the importance of segmentation in annelids?
Answer:
The importance of segmentation in annelids:

1. Segmentation divides the body into repeating units.
2. This allows greater flexibility and better control of movement.
3. It also allows for organ system level organisation, where different segments can specialise for different functions.

Question 9.
Name the five classes of vertebrates and give one distinguishing feature of each.
Answer:
The five classes of vertebrates and one key feature of each are:

1. Fish: breathe through gills.
2. Amphibians: live on land and water, with moist skin.
3. Reptiles: have dry scaly skin and lay shelled eggs on land.
4. Birds: have feathers and hollow bones for flight.
5. Mammals: feed their young with milk from mammary glands.

Question 10.
What are the rules for writing scientific names?
Answer:
The rules for writing scientific names are:

1. The name should have two parts: genus and species.
2. The genus name should begin with a capital letter and come first.
3. The species name should be written in lower case.
4. The complete name should be italicised in print and underlined when handwritten.
   Example: Mangifera indica (mango).

Patterns in Life Diversity and Classification Class 9 Long Question Answer

Question 1.
Explain why India is considered a biodiversity hotspot. Discuss the role of different habitats in supporting this biodiversity.
Answer:
India has a diverse natural landscape that includes:

1. Mountains in the north (Himalayas)
2. Desert in the west (Thar)
3. Rainforests in the North East (Kaziranga National Park.
4. Plateaus in the south (The Deccan Plateau)
5. Long coastlines along the Arabian Sea and the Bay of Bengal.

Each region has distinct soil types and different climatic conditions like temperature and rainfall. These diverse habitats support a wide variety of species, many of which are endemic (found only in India), such as Nilgiri tahr, Lion-tailed macaque and Neelakurinji. Regions like the Western Ghats and Indo- Burma are recognised as global biodiversity hotspots because they contain many endemic species and have experienced significant habitat loss. Protecting these regions is crucial for maintaining food webs and keeping ecosystems healthy.

Question 2.
Describe the evolution of classification systems from Aristotle to Whittaker.
Answer:
Classification systems have evolved overtime as new knowledge became available.

• Aristotle (4th century BCE) grouped animals by habitat (land, water, air) and external features, but this system had limitations.
• Linnaeus (1758) introduced the Two Kingdom System (Plantae and Animalia), but organisms like Amoeba and bacteria did not fit neatly.
• Haeckel (1866) added a third kingdom, Protista, for unicellular microscopic organisms.
• Copeland (1938) recognised that bacteria (prokaryotes) are fundamentally different from eukaryotic protists and created Kingdom Monera, forming a Four Kingdom System.
• Whittaker (1969) separated fungi from plants due to their heterotrophic nutrition and chitin cell walls, forming the Five Kingdom System— Monera, Protista, Fungi, Plantae and Animalia.

Each change reflected new scientific discoveries and tools, showing that classification is an ongoing, evolving process.

Question 3.
Describe the five classes of Kingdom Plantae with one example each. How do they show increasing complexity?
Answer:
The five classes of Kingdom Plantae, in order of increasing complexity:

1. Thallophvta (e.g. Spirogyra): Simplest plants with an undifferentiated thallus body, mostly aquatic.
2. Bryophyta (e.g. moss): First plants on land; have rhizoids and simple leaf-like structures but no vascular tissue. Need water for reproduction.
3. Pteridophyta (e.g. fern): Have true roots, stems, leaves and vascular tissues (xylem and phloem), but still need water for reproduction. No seeds.
4. Gymnosperms (e.g. pine): Produce seeds on cones (not enclosed in fruits). Needle-like leaves reduce water loss. Do not need water for fertilisation.
5. Angiosperms (e.g. mango): Flowering plants with seeds enclosed in fruits. Most complex body organisation.

This classification shows a clear progression from water-dependent simple forms to complex land- adapted plants with flowers, fruits and efficient seed dispersal.

Question 4.
Discuss the increasing complexity in body organisation from Porifera to Echinodermata.
Answer:
From Porifera to Echinodermata, animal body organisation shows a steady increase in complexity:

• Porifera (sponges): Simplest, with cellular level organisation; no tissues or orgAnswer:
• Cnidaria (e.g. Hydra): Tissue level organisation with specialised cells like tentacles for catching prey.
• Platyhelminthes (flatworms): Bilateral symmetry and organ level organisation. Single opening for food and waste.
• Nematoda (roundworms): Complete digestive system with two openings (mouth and anus).
• Annelida (earthworms): Segmented body and organ system level organisation with a body cavity.
• Arthropoda (insects, crabs): Jointed appendages and a protective exoskeleton.
• Mollusca (snails): Soft bodies often protected by shells; organ system organisation.
• Echinodermata (starfish): Internal skeleton of calcium carbonate.

This progression shows a step-by-step increase in body complexity, from simple cellular organisation to complex organ systems with internal support.

Patterns in Life Diversity and Classification Class 9 Case Based Questions

I. The Pakke Tiger Reserve in Arunachal Pradesh is a forest where scientists have recorded nearly 300 bird species. Pakke is known for supporting four species of hornbills: the Rufous-necked Hornbill, the Oriental Pied Hornbill, the Great Hornbill and the Wreathed Hornbill. These large birds nest only in large, old trees with suitable cavities and feed on specific fruits. Different hornbill species are found in different parts of the forest depending on tree size and fruit availability.

Answer the following questions:

Question 1.
How many bird species have been recorded at Pakke Tiger Reserve?
Answer:
Nearly 300 bird species have been recorded at Pakke Tiger Reserve.

Question 2.
Why are different hornbills found in different parts of the forest?
Answer:
Different hornbill species are found in different parts of the forest because they depend on specific tree sizes for nesting and particular fruits for food. The distribution of suitable trees and fruits varies across the forest.

Question 3.
What would happen if the large, old trees disappeared from the forest?
Answer:
If the large, old trees disappeared, the hornbills would lose their nesting sites. This would lead to a decline in hornbill populations and could eventually lead to their local extinction, disrupting the forest ecosystem.

Question 4.
How does classifying the four hornbill species help us understand biodiversity?
Answer:
Classifying them helps scientists identify and distinguish each species, study their unique features, understand their habitat needs and monitor their populations. This knowledge is essential for targeted conservation efforts.

II. Cyanobacteria (blue-greenalgae) were among the first organisms to produce oxygen through photosynthesis. About 2.5 billion years ago, oxygen accumulated in the atmosphere and made the Earth suitable for other forms of life. Fossils of ancient cyanobacteria are found in structures called stromatolites. They have been found in Rajasthan and Madhya Pradesh and provide some of the earliest evidence of life on Earth.

Answer the following questions:

Question 1.
In which kingdom are cyanobacteria classified?
Answer:
Kingdom Monera.

Question 2.
Why are cyanobacteria important for life on Earth?
Answer:
Cyanobacteria were among the first organisms to produce oxygen through photosynthesis. This oxygen accumulated in the atmosphere and made the Earth suitable for other oxygen-dependent life forms.

Question 3.
What are stromatolites?
Answer:
Stromatolites are layered rock structures formed by ancient cyanobacteria. They provide some of the earliest evidence of life on Earth.

Question 4.
Are cyanobacteria prokaryotes or eukaryotes? Give a reason.
Answer:
Cyanobacteria are prokaryotes because their cells lack a membrane-bound nucleus.

III. Floating grasslands, locally known as phumdis, are one of the unique habitats in the world. They are located in Loktak Lake of the Keibul Lamjao National Park in Manipur, India. The habitat supports the endangered Sangai (the dancing deer), which is endemic to Manipur. The deer was declared extinct in 1951 but was rediscovered in 1953 based on its unique characteristics. Recently, the phumdis are degenerating and the Sangai deer is listed in the IUCN Red Data List.

Answer the following questions:

Question 1.
What are phumdis?
Answer:
Phumdis are floating beds of soil with rooted vegetation and rich organic matter found in Loktak Lake, Manipur. Their thickness varies from a few centimetres to two metres.

Question 2.
Why is the Sangai deer called endemic?
Answer:
The Sangai deer is called endemic because it is found only in Manipur, India, and nowhere else naturally in the world.

Question 3.
How was the Sangai deer rediscovered after being declared extinct?
Answer:
Naturalists rediscovered the Sangai deer in 1953 by identifying it based on its unique characteristics, such as its distinctive hooves and elongated patterns.

Question 4.
Suggest two measures to conserve the Sangai deer and its habitat.
Answer:
(a) Protecting and restoring the phumdis by preventing pollution and controlling water levels in Loktak Lake.
(b) Declaring the area a strict conservation zone and limiting human activities that degrade the habitat.

Patterns in Life Diversity and Classification Extra Questions for Practice

Very Short Answer Type Questions

Question 1.
What is the meaning of the word ‘gymnosperm’?

Question 2.
Name the organism that is unicellular yet placed in Kingdom Fungi.

Question 3.
What are rhizoids?

Question 4.
Define saprophyte.

Question 5.
Write the scientific name of mango.

Question 6.
What type of nutrition do plants show?

Question 7.
Which phylum has organisms with a single opening for food intake and waste removal?

Question 8.
Name the kingdom that includes unicellular prokaryotes.

Question 9.
What are protochordates?

Question 10.
Give one example of a biodiversity hotspot in India.

Short Answer Type Questions

Question 1.
Why is biological classification important?

Question 2.
How do fungi play an important ecological role?

Question 3.
Differentiate between gymnosperms and angiosperms.

Question 4.
Why did scientists separate Monera from Protista?

Question 5.
What are the advantages of the binomial nomenclature system?

Question 6.
Why is biodiversity important for ecosystems?

Question 7.
Compare Porifera and Cnidaria in terms of body organisation.

Long Answer Type Questions

Question 1.
Explain the hierarchical nature of classification with the example of a tiger.

Question 2.
Describe the main characteristics of each of the five kingdoms with examples.

Question 3.
How do invertebrate phyla show increasing complexity from Porifera to Echinodermata?

Question 4.
Explain how plant diversity reflects solutions to the challenges of life on land.

Question 5.
Describe the three-domain system proposed by Carl Woese. How is it different from the five- kingdom system?

Question 6.
Discuss the threats to biodiversity and suggest measures for conservation.

Question 7.
Explain with examples how fossils help us understand the history of life on Earth.