The Beauty of Diversity Class 8 Questions and Answers Notes Basic Science Chapter 17 Kerala Syllabus

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Class 8 Basic Science Chapter 17 The Beauty of Diversity Question Answer Notes

Class 8 Basic Science Chapter 17 Notes Kerala Syllabus The Beauty of Diversity Question Answer

The Beauty of Diversity Class 8 Questions and Answers Notes

Let’s Assess

Question 1.
Based on Box A, identify and write the appropriate items from Boxes B and C.

A	B	C
1. Parasitism	a. At first, harm to both; later, benefit for the winner.	a. Butterfly and the flower.
2. Predation	b. Beneficial to one, neither beneficial nor harmful to another.	b. Vanda and mango tree.
3. Commensalism	c. Beneficial to both organisms.	c. Tiger and deer.
4. Mutualism	d. Beneficial to one, harmful to another. The prey becomes food for the predator.	d. Weed and crop.
5. Competition	e. One benefits, the other is harmed.	e. Cat and flea.

Answer:

A (Interaction)	B (Description)	C (Example)
1. Parasitism	e. One benefits, the other is harmed.	Cat and flea.
2. Predation	d. Beneficial to one, harmful to another. The prey becomes food for the predator.	Tiger and deer.
3. Commensalism	b. Beneficial to one, neither beneficial nor harmful to another.	Vanda and mango tree.
4. Mutualism	c. Beneficial to both organisms.	Butterfly and the flower.
5. Competition	a. At first, harm to both; later, benefit for the winner.	Weed and crop.

Question 2.
Examine the illustration and answer the following questions.

a) Rearrange the given food chain in the correct order.
b) Identify and write the producer, primary consumer, secondary consumer and tertiary consumer in the food chain.
c) Which organism belongs to the third trophic level in this food chain?
d) If the fish in this food chain completely disappear, how would it affect the ecosystem?
Answer:
a) Algae → Tadpole → Fish → Kingfisher
(Reasoning: Algae are producers (plants). Tadpoles eat algae. Fish eat tadpoles. Kingfishers eat fish.)

b)

• Producer: Algae (Makes its own food).
• Primary Consumer: Tadpole (Eats the producer).
• Secondary Consumer: Fish (Eats the primary consumer).
• Tertiary Consumer: Kingfisher (Eats the secondary consumer).

c) Fish
(Reasoning: Trophic Level 1 = Producer (Algae); Trophic Level 2 = Primary Consumer (Tadpole); Trophic Level 3 = Secondary Consumer (Fish)).

d)

• The Kingfisher population might decrease or move elsewhere due to a lack of food (fish).
• The Tadpole population might increase significantly because their main predator (fish) is gone.
• An increase in tadpoles could lead to a decrease in the Algae population due to overgrazing.
• This disrupts the balance of the ecosystem.

Question 3.
A food chain created by a student is given below. Examine it and answer the following questions.

a) Is the food chain created by the student correct? What is your opinion? What is the justification for it?
b) What would happen if decomposers like bacteria did not exist?
c) Write an example of a decomposer other than bacteria.
Answer:
a) No, the food chain is incorrect.
Justification: A food chain shows the flow of energy from producers to consumers. Bacteria are decomposers, not consumers. Decomposers break down dead organic matter from all trophic levels (including dead paddy plants), but they are not typically shown as the next step after a producer in a simple feeding chain. A correct chain would be Paddy Plant Herbivore (e.g., Rat).

b) If decomposers did not exist, dead plants and animals would not break down effectively. Nutrients locked within this dead organic matter would not be returned to the soil, water, and air. Over time, producers (plants) would run out of essential nutrients, and the entire ecosystem would eventually collapse. Dead bodies would accumulate everywhere.

c) Fungi (e.g., mushroo1ms, mould).

Basic Science Class 8 Chapter 17 Question Answer Kerala Syllabus

Texbook Page No : 269

Question 1.
Which are the living organisms that you see in the picture (Biodiversity Park)?
Answer:
Based on a typical biodiversity park setting, one would see trees, flowering plants, students (humans), birds, butterflies, and potentially insects on the ground.

Question 2.
In what different ways can you classify the organisms you identified?
Answer:

• Plants vs. Animals: Trees and bushes vs. Birds and Humans.
• Vertebrates vs. Invertebrates: Birds / Humans vs. Insects.
• Terrestrial vs. Aquatic: If there is a pond, organisms can be classified by where they live.:

Question 3.
Apart from the organisms you identified in the picture, what other organisms can be seen in a biodiversity park?
Answer:
Soil organisms (earthworms, millipedes), microorganisms (bacteria, fungi), reptiles (lizards, garden snakes), and various insects (ants, beetles).

Question 4.
Why is this place called a biodiversity park?
Answer:
Because it is a protected area designed to conserve a wide variety of plant and animal species (biodiversity) in one location, allowing them to thrive in their natural habitat.

Textbook Page No : 270 & 271

Question 5.
What conclusions can we arrive about the biodiversity?
Answer:
Biodiversity is vast and not yet fully discovered. Even today, hundreds of new species are being found, indicating that our forests and ecosystems hold many secrets and hidden species.

Question 6.
What are the organisms found only in these habitats?
Answer:
Organisms have specific adaptations that limit them to particular environments.

• Coral Reef: Corals, sea anemones, clownfish, starfishes.
• Mangrove Forest: Mangrove trees (plants with breathing roots), mud-skippers (fish that can move on mud), crabs, water birds.
• Desert: Cactus plants (modified leaves to save water), camels, rattle snakes, scorpions.
• Wetlands: Water lilies, lotus, frogs, cranes, dragonflies.

Question 7.
What are the non-living (abiotic) factors that help the survival of organisms in these habitats?
Answer:
Abiotic factors are the non-living parts of the environment that influence living organisms.

• Coral Reef: Saline (salty) water, sunlight penetration, steady water temperature. dissolved oxygen.
• Mangrove Forest: Brackish water (mix of salt and fresh water), clay-rich/muddy soil, tides,
• Desert: High temperature, intense sunlight, scarcity of water, sandy soil.
• Wetlands: Abundance of fresh water, marshy soil, moderate temperature.

Let’s Find

Question 8.
“Some organisms are able to live only in certain habitats. Why?”
Answer:
Organisms have specific adaptations (physical features or behaviors) evolved over huge periods of time that allow them to survive only in specific conditions (e.g., gills for breathing in water, thick fur for warmth in polar regions).

Question 9.
Have you noticed that a single organism can exist in different forms as shown in the pictures?
Answer:
Yes. Some organisms undergo a process called metamorphosis, where they change their form completely during their life cycle.
butterfly (Egg → Larva/Caterpillar → Pupa → Adult) or a frog (Egg → Tadpole → Frog).
Example: A frog starts as an egg, hatches into a tadpole (which lives in water and has a tail), and eventually grows legs and loses its tail to become an adult frog. This allows the organism to live in different ecosystems (water vs. land) at different stages of its life.

Textbook Page No : 273 & 274

Question 10.
Identify and write down which level of biodiversity that each of the following represents. (Based on Illustration 17.1: Ecosystem diversity, Species diversity, Genetic diversity).


Answer:

Question 11.
What does the poster (Illustration 17.2) indicate?

Answer:
It highlights the “International Day for Biodiversity” (May 22) and the theme “Our biodiversity, our food, our health,” emphasizing that our survival depends on nature.

Question 12.
How does biodiversity benefit each living organism?
Answer:
It provides food, shelter, oxygen, and maintains the ecological balance necessary for survival.

Question 13.
Shall we collect information on these topics and organize a seminar in the class on the topic “Biodiversity and the Survival of Living Beings”.
Seminar subtopics
• Food, clothing, shelter, fuel, medicines and biodiversity.
• Biodiversity and the stability of soil, water and air.
• Biodiversity in nutrient cycling, pollination, biological control and seed dispersal.
• Biodiversity and aesthetic values.
Answer:
□ Food, Clothing, Shelter, Fuel, Medicines, and Biodiversity
This section highlights the direct utilization of biodiversity by humans.

□ Biodiversity and the Stability of Soil, Water, and Air
This section focuses on the regulatory and life-support services of ecosystems.
Soil Stability:

• Plant Roots bind the soil together, preventing soil erosion by wind and water.
• Decomposers (like earthworms, bacteria, and fungi) enrich the soil by breaking down organic matter, increasing its fertility and water retention capacity.
• Water Stability (Hydrological Cycle):
  • Forests (especially rainforests and hill forests) act as natural sponges, regulating the flow of water. They absorb rainfall, reduce surface runoff, and slowly release water into streams, preventing floods and maintaining water tables.
  • Wetlands filter pollutants from water.
• Air Quality and Stability:
  • Plants (Producers) are responsible for taking in atmospheric Carbon Dioxide (CO₂) and releasing Oxygen (O₂) during photosynthesis, maintaining breathable air quality. Large forest ecosystems help stabilize the global climate by acting as carbon sinks (absorbing CO₂).

□ Biodiversity in Nutrient Cycling, Pollination, Biological Control, and Seed Dispersal These are the essential functional roles (ecosystem services) provided by living organisms.

• Nutrient Cycling (e.g., Carbon Cycle):
  • Decomposers (bacteria and fungi) break down dead organisms, releasing essential nutrients (like nitrogen, phosphorus, and carbon) back into the soil and atmosphere for reuse by plants. This process is crucial for life to continue.
• Pollination:
  • Insects (like bees, butterflies), birds, and bats transfer pollen between plants, enabling reproduction in flowering plants. This is vital for the production of fruits, vegetables, and seeds.
• Biological Control:
  • Nature uses natural predators and parasites to keep pest populations in check, reducing the need for harmful chemical pesticides.
  • Example: Ladybugs eat aphids (plant pests).
• Seed Dispersal:
  • Animals (e.g., birds, squirrels, elephants) eat fruits and carry the seeds elsewhere, often depositing them in fertile soil via their droppings, which helps plants colonize new areas. This is crucial for forest regeneration.

□ Biodiversity and Aesthetic Values
This section discusses the intangible, non-material benefits of biodiversity.

• Aesthetic Appeal: The beauty of nature, including colorful flowers, diverse wildlife, majestic landscapes, and vibrant coral reefs, provides profound sensory and emotional satisfaction.
• Recreation and Ecotourism: Natural areas (national parks, sanctuaries, beaches) are destinations for relaxation, learning, and tourism. This supports local economies.
• Cultural and Spiritual Value: Many indigenous communities and cultures have deep, spiritual connections to specific plants, animals, or natural sites (e.g., sacred groves).
• Education and Research: Biodiversity provides a living laboratory for scientific research, helping us understand genetics, ecology, and evolution.

Textbook Page No : 275
Indicators

Question 14.
From whom does the food chain begin?
Answer:
The food chain begins with Producers (Paddy green plants/algae).

Question 15.
Why are green plants called producers?
Answer:
They are the only organisms capable of producing their own food using solar energy and simple substances through photosynthesis.

Question 16.
Who are the consumers?
Answer:
The consumers are organisms that feed on producers or other consumers. In the example: Rat (Primary), Snake (Secondary), and Eagle (Tertiary).

Question 17.
What is the characteristic of primary consumers?
Answer:
They are herbivores; they feed directly on the producers (green plants).

Question 18.
What is the characteristic of second ary consumer s?
Answer:
They are carnivores or omnivores; they feed on the primary consumers (herbivores).

Question 19.
Who are the tertiary consumers?
Answer:
They are carnivores; they feed on the secondary consumers.

Question 20.
What is the role of decomposers in the food chain?
Answer:
Decomposers (like Bacteria and Fungus) break down the complex organic matter in dead organisms and remains into simpler molecules, returning essential substances and elements to nature. They play a vital role in the flow of matter.

Question 21.
Create a food web using the given organisms

Answer:
The food web starts with the Producers (Trophic Level 1) and shows how energy flows up through the different Consumers.

1. Producers (Trophic Level 1)
Plant: Produces its own food (often including Grass/Paddy/other generic plants as assumed for the ecosystem).

2. Primary Consumers (Trophic Level 2 – Herbivores)
These organisms feed directly on the Plant:

• Deer
• Rabbit
• Rat (Also an Omnivore, but eats seeds/plants)
• Grasshopper
• Squirrel

3. Secondary Consumers (Trophic Level 3 – Primary Carnivores/Omnivores)
These organisms feed on the Primary Consumers:

• Snake: Eats Rat, Frog.
• Fox: Eats Rabbit, Rat, Squirrel, Grasshopper, Frog.
• Frog: Eats Grasshopper.
• Calotes (Lizard): Eats Grasshopper.
• Vulture: Eats dead or dying animals (Scavenger, but occupies this level when eating small, newly dead herbivores).

4. Tertiary Consumers (Trophic Level 4 – Secondary Carnivores)
These organisms feed on Secondary Consumers:

• Tiger: Eats Deer (Primary Consumer) and Fox (Secondary A Tertiary Consumer).
• Fox: Eats Snake, Frog, Calotes.
• Vulture: Eats dead or dying animals (Scavenger, but occupies this level when eating larger, newly dead carnivores like snakes/foxes).

Text Book Page No : 276
Indicators

Question 22.
Trophic level with the maximum number of organisms:
Answer:
Trophic Level 1 (Producers). The base of the pyramid is always the largest.

Question 23.
Trophic level with the least number of organisms.
Answer:
The highest trophic level (e.g., Trophic Level 4, Tertiary Consumers). Energy is lost at each step, supporting fewer organisms at higher levels.

Question 24.
How does the disappearance of top-level organisms affect balance?
Answer:
The disappearance of top predators can lead to an overpopulation of organisms in the lower trophic levels (e.g., secondary consumers). This imbalance can disrupt the entire food web and ecosystem stability (e.g., herbivores might overgraze if their predators disappear).

Text Book Page No : 277

Question 25.
Types of Interactions (Illustration 17.5):

Answer:
Commensalism:
Example: Vanda (orchid) growing on a Tree. (Vanda gets support, tree is unaffected)

Mutualism:
Example: Tree providing nectar to a Butterfly, which helps in pollination. (Lichens are another example).

Competition:
Example: Crop plants and Weeds competing for nutrients and space.

Parasitism:
Example: Flea living on a Dog. (Other examples: intestinal worms, lice).

Predation:
Example: Eagle hunting a Chicken. (Other examples: Tiger hunting deer, Snake eating rat).

Text Book Page No : 278 & 279

Question 26.
Are such relationships necessary to maintain the balance and stability of an ecosystem? Discuss.
Answer:
Yes, ecological relationships are absolutely necessary to maintain the balance and stability of an ecosystem.
They ensure:

Population Control (Predation & Competition): Relationships like predation prevent overpopulation of certain species (prey), which stops them from destroying producers (plants).
Competition limits resource dominance, ensuring diversity.

Energy Flow and Cycling (Food Webs & Decomposers): They facilitate the continuous flow of energy from producers to consumers and the crucial recycling of nutrients (like carbon and nitrogen) back into the soil and atmosphere by decomposers.

Survival and Reproduction (Mutualism): Relationships like mutualism (e.g., pollination) are vital for the reproduction and survival of many plant and animal species.
Essentially, these interdependencies create a resilient web of life; if one part is lost, the entire system can collapse, making these connections essential for ecological balance.

Indicators
Question 27.
The ultimate source of energy in the food chain.
Answer:
The Sun

Question 28.
Storage of solar energy in producers.
Answer:
Plants absorb light and convert it into chemical energy via photosynthesis.

Question 29.
Energy transfer and energy loss.
Answer:
Energy is transferred from one level to the next (Plant → Herbivore → Carnivore). However, a portion is lost as heat at each stage for bodily functions.

Question 30.
Energy availability at different trophic levels.
Answer:
The amount of available energy decreases as you move up the trophic levels.

Question 31.
Which are the important elements and substances among them?
Answer:
The most important elements and substances are the basic building blocks and energy sources of life:
Elements: Carbon (C), Hydrogen (H), Oxygen (O), Nitrogen (N), and Phosphorus (P).
Substances: Water (H₂O), Proteins, Carbohydrates, and Fats (Lipids).

Text Book Page No : 280
Indicators

Question 32.
In what form is carbon present in the atmosphere?
Answer:
As Carbon dioxide (CO₂).

Question 33.
Why do plants use carbon dioxide?
Answer:
To perform photosynthesis and produce food.

Question 34.
How does carbon dioxide return to the atmosphere?
Answer:
Through the respiration of living organisms, decomposition of dead matter, and combustion (burning) of fossil fuels.

Question 35.
What situations lead to an increase in atmospheric carbon dioxide?
Answer:
Excessive burning of fossil fuels (factories, vehicles) and deforestation (cutting down trees).

Question 36.
How does biodiversity conservation help in maintaining carbon balance?
Answer:
Plants/Forests absorb large amounts of CO₂. Protecting them ensures that CO₂ levels in the atmosphere are regulated.

Question 37.
Collect information and illustrate other material cycles.
Water cycle Nitrogen cycle
Answer:
Water Cycle (Hydrologic Cycle)
Water constantly moves between the Earth and the atmosphere through changes in state.
Evaporation/Transpiration:Water turns into vapor and rises to the atmosphere.
Condensation: Vapor cools and forms clouds.
Precipitation: Water falls back as rain, snow, etc.
Runoff/Infiltration: Water flows over or soaks into the ground.
Nitrogen Cycle
Nitrogen is converted into usable forms by bacteria for living things.
Nitrogen Fixation: Bacteria convert atmospheric Nitrogen gas (N₂) into Ammonia (usable form).
Assimilation: Plants absorb this nitrogen to make proteins/DNA.
Nitrification: Bacteria convert Ammonia to Nitrates (preferred plant food).
Denitrification: Other bacteria return nitrogen compounds back to Nitrogen gas (N₂) in the atmosphere.

Text Book Page No : 281
Indicators

Question 38.
What would happen if decomposers disappeared?

Answer:
Fig 17.6 shows a dense, healthy forest. Fig 17.7 shows a developed city area where the forest has been destroyed.

Question 39.
How does deforestation affect other living beings?
Answer:
It destroys habitats, causing food scarcity and death for wild animals, leading to species extinction.

Question 40.
Are all the organisms that once lived in your area still seen today?
Answer:
No. Many organisms have disappeared (become locally extinct or extirpated) due mainly to habitat loss and pollution.

Question 41.
Is biodiversity in our area increasing or decreasing?
Answer:
Decreasing. In most regions, the expansion of human settlements and activities leads to biodiversity depletion (loss of species and ecosystems).

Question 42.
Is this kind of biodiversity loss happening only in our region?
Answer:
No. It is a global phenomenon that is happening all over the world. The crisis is tracked globally by organizations like IUCN.

Text Book Page No : 282 & 283

Question 43.
Can we protect all species at all times?
Answer:
No. While the goal is protection, limited resources and changing environments mean conservation efforts often prioritize rare and endangered species (like those in the Red Data Book).

Question 44.
Is it possible to fulfill human needs and conserve biodiversity at the same time?
Answer:
Yes. It requires careful planning and implementation of conservation strategies, such as In-situ conservation (protecting natural habitats) and Ex-situ conservation (protecting species outside their habitat).

Question 45.
What are the reasons for wild animals to enter human settlements?
Answer:
The main reasons are the depletion of resources and loss of habitat within the forest. For example, intensifying summer heat can drive animals like elephants into settlements in search of food and water.

Question 46.
Can you suggest any solutions to this problem?
Answer:
Using Al technology to generate sounds to drive wild animals back into the forest.
Preparing special sanctuaries or shelters outside the forest to house animals like tigers.
Providing adequate compensation to farmers for crop damage.

Question 47.
Why is it necessary to conserve biodiversity?
Answer:
Biodiversity is necessary because it ensures human survival by providing:

• Food (fruits, vegetables, fish, etc.).
• Medicine (many modern medicines are made from plants and other organisms).
• Ecosystem Services (creatures like bees help in pollination).
• Clean Air and overall environmental health.

Question 48.
What are the organizations in our country that work for nature conservation?
Answer:
There are various government institutions, schemes, and local bodies that work for conservation:

• Kerala State Biodiversity Board
• Biodiversity Management Committees (BMC) at the local self-government level, which prepare the People’s Biodiversity Register (PBR).
• (Internationally, WWF and IUCN are mentioned as examples).

Class 8 Basic Science Chapter 17 Question Answer Extended Activities

Question 1.
Examine the People’s Biodiversity Register (PBR) of the local self-government body (Panchayat/Municipality / Corporation) where your school is located. List the species found under each category and their current status (increasing/decreasing). Present your findings in the class.

Question 2.
Plant at least 10 different types of plants at your home and make a small garden. Before making your garden, record the organisms that were already present and the composition of the soil. After one month of planting, observe and record the changes that occurred. Present your findings and conclusions in the class.

The Beauty of Diversity Class 8 Notes

Class 8 Basic Science The Beauty of Diversity Notes Kerala Syllabus

Introduction: Biodiversity

• Biodiversity Park: A place (like in a school) that showcases a variety of living organisms, both plants and animals, in their natural setting. It’s called a biodiversity park because it contains diverse life forms.
• Biodiversity: Refers to the vast variety of life forms found on Earth, including plants, animals, fungi, microorganisms, etc.

ജീവവൈവിധ്യം (Biodiversity) എന്നാൽ ഭൂമിയി ലുള്ള വിവിധ തരത്തിലുള്ള ജീവജാലങ്ങൾ (സസ്യ ങ്ങൾ, ജന്തുക്കൾ, സൂക്ഷ്മജീവികൾ) എന്നാണ് അർത്ഥമാക്കുന്നത്. ഒരു ജൈവവൈവിധ്യ പാർക്ക് (Biodiversity Park) എന്നാൽ ഇത്തരത്തിലുള്ള വിവിധ ജീവജാലങ്ങളെ ഒരുമിച്ച് കാണാൻ കഴി യുന്ന ഒരിടമാണ്.

Habitat(ആവാസവ്യവസ്ഥ)

• The natural surroundings where each living being lives is called its habitat.
• Examples of Habitats (Fig 17.3):

• • Coral reef (പവിഴപ്പുറ്റ്)
  • Mangrove Forest (കണ്ടൽക്കാട്)
  • Desert (മരുഭൂമി)
  • Wetlands (തണ്ണീർത്തടം)
• Habitat Examples (Fig 17.2):

• • Hibiscus Plant: Land
  • Fish: Water (Ocean/Sea)
  • Frog: Land and Water (Amphibious)
  • Polar Bear: Polar regions (Snow/Ice)

ഓരോ ജീവിയും സ്വാഭാവികമായി ജീവിക്കുന്ന ചുറ്റുപാടിനെയാണ് അതിന്റെ ആവാസവ്യവസ്ഥ (Habitat) എന്ന് പറയുന്നത്. കര, ജലം, മരുഭൂമി, ധ്രുവപ്രദേശങ്ങൾ എന്നിവയെല്ലാം വിവിധതരം ആവാസവ്യവസ്ഥകളാണ്.

Lichens (ലൈക്കനുകൾ)
Lichens are an example of a symbiotic relationship and contribute to biodiversity.

• Structure: Some algae or cyanobacteria live inside certain fungi.
• Symbiosis (സഹജീവനം): This is a mutually beneficial relationship.
  • The fungus provides structure and protection.
  • The algae or cyanobacteria produce food for both organisms through photosynthesis.
• The symbiotic organisation of these organisms is known as lichens.

ലൈക്കനുകൾ എന്നത് ഫംഗസുകളും ആൽഗകളും (അല്ലെങ്കിൽ സയനോബാക്ടീരിയകളും ഒരുമിച്ച് ജീവിക്കുന്ന ഒരു കൂട്ടായ്മയാണ്. ഫംഗസ് സംര ക്ഷണവും ഘടനയും നൽകുമ്പോൾ, ആൽഗകൾ പ്രകാശസംശ്ലേഷണം (photsoynthesis) വഴി രണ്ടുപേർക്കും വേണ്ട ആഹാരം നിർമ്മിക്കുന്നു. ഇത് സഹജീവനത്തിന് (symbiosis) ഒരു ഉദാഹ രണമാണ്.

Biodiversity (ജീവവൈവിധ്യം)
Biodiversity refers to all the diverse living organisms on Earth, including plants, animals, and microorganisms, along with their habitats.

• Operational Definition: “All the diverse living organisms on Earth, including plants, animals, and microorganisms, along with their habitats, together form biodiversity.”
• Variation: Even within a single species, variations can exist (e.g., different colours of hibiscus flowers, different types of ants – Fig 17.4).
  There are over 15,000 types of ants discovered, adapted to various habitats like deserts, rainforests, and mountains.

Levels of Biodiversity (ജീവവൈവിധ്യത്തിന്റെ തലങ്ങൾ)
Biodiversity can be studied at different levels (Illustration 17.1):

• Genetic Diversity (ജനിതക വൈവിധ്യം):
  • Variation within a species.
  • Example: Different varieties of rice (over 50,000 in India) or mangoes (over 1,000 varieties in India) show genetic diversity. Different breeds of dogs or different colours of hibiscus flowers also represent this.
• Species Diversity (സ്പീഷീസ് വൈവിധ്യം):
  • Species-level diversity; the variety of different species within a particular area or habitat.
  • Example: In a forest, there are elephants, monkeys, birds, snakes, grasses. bacteria, etc. – all different species living together.
• Ecosystem Diversity (ആവാസവ്യവസ്ഥാ വൈവിധ്യം):
  • Diversity at the ecosystem level; the variety of different habitats or ecosystems within a larger region.
  • Example: In a village, there might be paddy fields, coconut groves, hills, rivers, and marshes – each representing a different ecosystem. Coral reefs, mangrove forests, deserts, and wetlands are also examples of different ecosystems.

ജീവവൈവിധ്യത്തെ മൂന്ന് തലങ്ങളിൽ പഠിക്കാം:

• ജനിതക വൈവിധ്യം: ഒരു സ്പീഷീസിനുള്ളി ലെ വ്യതിയാനങ്ങൾ (ഉദാ: വിവിധയിനം നെല്ലുകൾ, മാവുകൾ).
• സ്പീഷീസ് വൈവിധ്യം: ഒരു പ്രദേശത്തുള്ള വ്യത്യസ്ത സ്പീഷീസുകളുടെ എണ്ണം (ഉദാ: കാട്ടിലെ ആന, കുരങ്ങ്, പാമ്പ് തുടങ്ങിയവ).
• ആവാസവ്യവസ്ഥാ വൈവിധ്യം: ഒരു വലിയ പ്രദേശത്തെ വിവിധതരം ആവാസവ്യവസ്ഥ കൾ (ഉദാ: വയൽ, കാവ്, പുഴ, കുളം എന്നിവ ചേർന്ന ഒരു ഗ്രാമം).

Importance of Biodiversity (ജീവവൈവിധ്യത്തിന്റെ പ്രാധാന്യം)
Biodiversity plays a crucial role in the survival of all living beings, including humans.
The theme “Our biodiversity, our food, our health” highlights this connection.

• Benefits / Roles of Biodiversity:
  • Provisioning Services: Provides essential resources like food, clothing, shelter, fuel, and medicines.
  • Regulating Services: Helps maintain the stability of soil, water, and air; plays a role in nutrient cycling (e.g., decomposition), pollination (പരാഗണം), biological control (ജൈവീക കീടനിയന്ത്രണം), and seed dispersal (വിത്ത് വിതരണം).
  • Supporting Services: Essential for processes like photosynthesis and soil formation.
  • Cultural & Aesthetic Values: Provides recreational opportunities, beauty, and inspiration.
• May 22 is celebrated as the International Day for Biodiversity.

Biodiversity and the Balance of the Eco system (ജീവവൈവിധ്യവും ആവാസവ്യവസ്ഥയുടെ സന്തുലനവും)
The interactions between different organisms are crucial for maintaining the balance and stability of an ecosystem. One key interaction is the flow of energy through feeding relationships, represented by food chains and food webs.

• Food Chain (ഭക്ഷ്യ ശൃംഖല)
  • A representation of how energy flows through an ecosystem, showing who eats whom.
  • Example (Illustration 17.3): Paddy → Rat → Snake → Eagle.

• • Components of a Food Chain (based on Indicators):
• Producers (ഉൽപ്പാദകർ):
  • Food chains begin with Producers.
  • Green plants are called producers because they produce their own food using sunlight (photosynthesis). They form the base of most food chains, (e.g., Paddy).
• Consumers (ഉപഭോക്താക്കൾ):
  • Organisms that obtain energy by feeding on other organisms.
  • Primary Consumers (പ്രാഥമിക ഉപഭോ ക്താക്കൾ): Herbivores that feed directly on producers (plants), (e.g., Rat eating paddy).
• Secondary Consumers ((ദ്വിതീയ ഉപഭോ ക്താക്കൾ):) Carnivores or omnivores that feed on primary consumers, (e.g., Snake eating rat).
• Tertiary Consumers (തൃതീയ ഉപഭോക്താക്കൾ): Carnivores or omnivores that feed on secondary consumers, (e.g., Eagle eating snake).
• Decomposers (വിഘാടകർ)::
  • Bacteria, fungi, and other organisms that break down complex molecules in dead bodies and other organic remains into simpler molecules.
  • Role: They return essential nutrients back to nature (soil, water, air), making them available for producers again, (e.g., Bacteria, Fungus).
• Food Web (ഭക്ഷ്യ ശൃംഖലാജാലം)
  • A network of interconnected food chains found in an ecosystem. Most organisms eat more than one type of food and are eaten by more than one type of predator.

Trophic Level (പോഷണ തലം)

• The position an organism occupies in a food chain is called a trophic level.

Trophic Level 1 : Producers (Plants).
Trophic Level 2 : Primary Consumers (Herbivores feeding directly on plants).
Trophic Level 3 : Secondary Consumers (Carnivores/Omnivores feeding on herbivores).
Trophic Level 4 : Tertiary Consumers (Carnivores/Omnivores feeding on secondary consumers).

• Complexity: As food webs become complex, a single organism can belong to different trophic levels depending on what it eats.

Ecological Interactions (പാരിസ്ഥിതിക ബന്ധങ്ങൾ)
Organisms in an ecosystem interact in various ways besides just eating each other. These relationships are necessary to maintain the balance and stability of the ecosystem.

Types of Interactions (Illustration 17.5):

• Commensalism:
  • Beneficial to one organism, neither beneficial nor harmful to the other.
  • Example: Vanda (orchid) growing on a Tree. (Vanda gets support, tree is unaffected).
• Mutualism:
  • Beneficial to both organisms.
  • Example: Tree providing nectar to a Butterfly, which helps in pollination. (Lichens are another example).
• Competition:
  • At first, harmful to both (as they compete for the same limited resources like sunlight, water, food); later, benefit for the winner.
  • Example: Crop plants and Weeds competing for nutrients and space.
• Parasitism:
  • Beneficial to one (the parasite), harmful to the other (the host). The parasite depends on the host for food.
  • Example: Flea living on a Dog. (Other examples: intestinal worms, lice).
• Predation:
  • Beneficial to one (the predator), harmful to the other (the prey). The prey becomes food for the predator.
  • Example: Eagle hunting a Chicken. (Other examples: Tiger hunting deer, Snake eating rat).

Energy Flow in an Ecosystem (ഊർജ്ജപ്രവാഹം ആവാസവ്യവസ്ഥയിൽ)
Energy is needed for all bodily functions and is transferred from one trophic level to the next in a food chain.

Role of Decomposers: Decomposers break down dead organic matter, releasing energy, but primarily returning nutrients (matter) to the ecosystem.

Flow of Matter in an Ecosystem (പദാർത്ഥങ്ങളുടെ ചാക്രിക പ്രവാഹം)
Various substances and elements are needed for life and must be cycled through the ecosystem. For ecosystems and biodiversity to survive, the flow of matter and energy must take place effectively. Substances absorbed from the non-living environment circulate through living organisms and return to where they came from. Food chains, biodiversity, and decomposers play vital roles in this.

Carbon Cycle (കാർബൺ ചകം)
Plants use atmospheric carbon dioxide for photosynthesis. Carbon returns to the atmosphere through respiration, decomposition, and combustion of fossil fuels.

• Atmospheric Carbon: Carbon exists in the atmosphere primarily as Carbon dioxide (CO₂).
• Photosynthesis: Plants absorb CO₂ and convert it into chemical energy (organic compounds).
• Respiration & Decomposition: Carbon returns to the atmosphere through the respiration of living organisms and the decomposition of dead matter.
• Combustion: Burning fossil fuels also releases CO₂ back into the atmosphere.
• Conservation: Conserving biodiversity helps maintain the carbon balance in ecosystems.

Biodiversity Depletion (ജീവവൈവിധ്യ ശോഷണം)
Human activities can severely damage eco-systems and lead to a loss of biodiversity.
Habitat Loss:

• Deforestation and human activities destroy natural habitats, forcing wild animals into human settlements.
• Pictures in the text contrast a natural forest with an industrialized/deforested area to highlight habitat destruction.
  • Human-Wildlife Conflict:
    Wild animals (like elephants and tigers) enter farmlands and settlements due to food scarcity and habitat loss, causing agricultural loss and danger to humans.
  • Technological Solution: Al technology is being used to detect animals via cameras and generate specific sounds to drive them back into the forest.
  • Unique Species:
    Purple Frog (Mahabali Frog): A rare frog that lives underground and surfaces only once a year to mate. It is called a “living fossil” because it has undergone very little evolutionary change since the time of the dinosaurs.

The Red Data Book:

• Publisher: IUCN (International Union for Conservation of Nature).
• Purpose: It contains information about rare and endangered plants and animals.
• Listed Species Examples: Malabar civet cat, Ganges Shark, Kashmir stag, Rameswaram Parachute spider, Lion-tailed macaque, and Nilgiri tahr.

• Importance of Conservation:
  • Biodiversity is essential for food, clean air, pollination, and medicines.
  • Medicinal Plants: Many modern medicines are derived from plants. Even plants considered “weeds” may have medicinal value.
• Conservation Organizations:
  • International: IUCN, WWF (World Wide Fund for Nature).

• • Local: Kerala State Biodiversity Board.

Methods of Biodiversity Conservation
Conservation is classified into two main types:

• In-situ Conservation
  Protection of organisms within their natural habitats.
  • National Parks: e.g., Eravikulam, Silent Valley.
  • Wildlife Sanctuaries: e.g., Periyar.
  • Biosphere Reserves: e.g., Nilgiri.
  • Community Reserves: e.g., Kadalundi.
  • Ecological Flotspots: e.g., Western Ghats, Himalayas.
• □ Ex-situ Conservation
  Protection of organisms outside their natural habitats in controlled environments.
  • Examples: Botanical gardens, Zoological gardens, Gene banks, Aquariums.