Maharashtra Board Class 7 Science Chapter 1 The Living World Adaptations and Classification Solutions

Find My Match!

Question a.

In simple words: This match-the-column exercise connects specific organisms with their key adaptations, demonstrating how they survive in different environments.

Answer:

🎯 Exam Tip: Understanding the unique adaptations of various plants and animals is crucial for scoring well in questions related to biodiversity and ecological niches.

I am a penguin. I live in polar region covered by snow. My abdomen is white. My skin is thick with a layer of fat underneath. My body is spindle-shaped. My wings are small. My toes are webbed. We live in flocks.

Question a.
Why is my skin white and thick and why is there a thick layer of fat underneath?
Answer:
1. White skin colour camouflage with the snow so penguins cannot be easily spotted and they get protected from enemies.
2. Thick skin and thick layer of fat underneath gives them protection from severe cold.
In simple words: A penguin's white, thick skin and fat layer help it blend into the snowy environment to avoid predators and insulate its body against extreme cold.

🎯 Exam Tip: When describing adaptations, always link the physical characteristic directly to its survival advantage in the specific environment.

Question b.
Why do we live in flocks sticking close to each other?
Answer:
Penguins live in flocks sticking close to each other because sticking close to each other reduce the relative area so there is least loss of heat and they get protection from cold.
In simple words: Penguins huddle in flocks to minimize heat loss, reducing their exposed surface area and helping them stay warm in the harsh polar climate.

🎯 Exam Tip: Social adaptations like huddling are important for survival in extreme conditions; remember to explain the biological benefit clearly.

Question c.
Which geographical region do I inhabit? Why?
Answer:
1. Penguins inhabit Antarctica region. Antarctica is surrounded by ocean. Climate is colder, drier and windier.
2. It does not have human population. This climate is suitable for penguins, so they inhabit Antarctica.
In simple words: Penguins live in Antarctica because its cold, dry, and windy conditions, along with minimal human disturbance, are perfectly suited for their survival and adaptations.

🎯 Exam Tip: Always provide a geographical location and specific environmental reasons when asked about habitats and 'why'.

Question d.
Which adaptations should you have to enable you to live permanently in the polar region? Why?
Answer:
1. I should be a warm blooded animal. This should allow me to permanently live in polar region.
2. My body has to be covered with thick fur or scale so that loss of heat will be very less and I can survive in severe cold.
In simple words: To live in a polar region, one would need to be warm-blooded and have a body covered with thick fur or scales to minimize heat loss and endure severe cold.

🎯 Exam Tip: Focus on physiological (warm-blooded) and structural (thick fur/scales) adaptations when discussing survival in extreme temperatures.

Who Is Lying?

Question a.
Cockroach - I have five legs.
Answer:
Cockroach is lying. It has six legs.
In simple words: The cockroach is lying; cockroaches are insects and have six legs, not five.

🎯 Exam Tip: For "Who is lying?" questions, state the lie clearly and then provide the accurate factual information.

Question b.
Hen - My toes are webbed.
Answer:
Hen is lying because hen's toes are not webbed. Duck has webbed toes.
In simple words: The hen is lying because hens do not have webbed feet; ducks are known for having webbed toes for swimming.

🎯 Exam Tip: Distinguish between different animal characteristics by focusing on specific adaptations like webbed feet for aquatic life.

Question c.
Cactus - My fleshy, green part is a leaf.
Answer:
Cactus is lying. It's fleshy, green part is a stem not a leaf.
In simple words: The cactus is lying; its fleshy, green part is actually a modified stem that performs photosynthesis, while its leaves are often reduced to thorns.

🎯 Exam Tip: Remember that in desert plants like cacti, stems are adapted for water storage and photosynthesis, differentiating them from typical leaves.

Read Each Of The Following Statements. Write A Paragraph About Adaptation With Reference To Each Statement.

Question a.
There is extreme heat in deserts.
Answer:
1. Plant's stem is fleshy, leaves get modified into thorns to reduce loss of water. Steam perform photosynthesis in the absence of leaves.
2. Animals have cushioned soles, hump, long legs and nostrils are protected by folds of skin. Eyelashes are long and thick.
In simple words: In deserts, plants adapt by having fleshy stems and thorn-like leaves to conserve water, while animals develop features like cushioned soles, humps, and protected nostrils to cope with heat and sand.

🎯 Exam Tip: When discussing desert adaptations, ensure you cover both plant and animal strategies, linking each feature to water conservation or protection from harsh conditions.

Question b.
Grasslands are lush green.
Answer:
Insects like grasshoppers have green colour so they can be camouflaged amidst grasses.
In simple words: The lush green color of grasslands provides excellent camouflage for insects like grasshoppers, helping them hide from predators.

🎯 Exam Tip: Camouflage is a key adaptation; always explain how an organism's coloring helps it blend into its specific environment for survival.

Question c.
We hide.
Answer:
In equatorial region grasses are very tall, so to protect themselves animals like tiger, elephants and deer remain hidden in these tall grasses.
In simple words: Animals like tigers, elephants, and deer hide in the tall grasses of equatorial regions for protection, using the vegetation as cover from predators.

🎯 Exam Tip: Explain how environmental features, such as tall grasses, provide protective adaptations for animals through concealment.

Question d.
We have long ears.
Answer:
It helps the animals to receive sounds from long distance, and they can protect themselves from predators.
In simple words: Animals with long ears can detect sounds from far away, allowing them to hear approaching predators and protect themselves.

🎯 Exam Tip: Emphasize how sensory adaptations, like long ears, directly contribute to an animal's ability to detect threats and ensure survival.

Answer The Following:

Question a.
Why is the camel called the 'ship of the desert'?
Answer:
1. Camel lives in a desert easily due to following adaptations. It has long legs and cushioned soles which keep the body of camel above the sand and cushioned soles do not allow to sink in sand while walking.
2. The nostrils are protected by folds of skin.
3. The eyelashes are long and thick.
4. It has hump which stores fats so it helps camel to survive in desert for many days without food and water.
Due to above adaptations camel is used to carry people and transport goods from one place to another place in the desert. Therefore, camel is called the ship of the desert.
In simple words: Camels are called 'ships of the desert' because their unique adaptations, like long legs, cushioned feet, protected nostrils, long eyelashes, and fat-storing humps, allow them to navigate and survive in harsh desert conditions, making them essential for transport.

🎯 Exam Tip: When explaining a title or nickname, detail multiple specific adaptations that justify the description, showing a comprehensive understanding.

Question b.
How can the plants like cactus and acacia live in deserts with scarce water?
Answer:
The plants like cactus and acacia live in deserts with scarce water due to the following adaptations.
1. Leaves are like small needles or have been modified into thorns, as a result they lose very little water by evaporation.
2. The stem stores water and food so it is fleshy.
3. The stems are green as they perform photosynthesis in the absence of leaves.
4. Their roots penetrate deep into the soil in search of water.
5. There is a thick layer of a waxy substance on the stems.
In simple words: Desert plants like cactus and acacia conserve water through adaptations like tiny or thorny leaves to reduce evaporation, fleshy stems for water storage and photosynthesis, deep roots to find water, and a waxy stem coating.

🎯 Exam Tip: List multiple adaptations and clearly explain how each one directly helps the plant survive in a water-scarce environment, such as a desert.

Question c.
What is the inter-relationship between adaptations of organisms and their surroundings?
Answer:
1. Adaptations of organisms depend on the changes in the surroundings.
2. To adjust with those changes in the surroundings adaptation takes place gradually and continuously in organisms.
3. Changes that take place in the various organs and life processes of organisms, enable them to live, feed, reproduce to perpetuate themselves and to protect themselves from their enemies in specific surroundings, depending upon the habitat and its geographical conditions, are called adaptations.
In simple words: Organisms adapt continuously in response to their changing surroundings, developing specific features in their bodies and life processes to survive, find food, reproduce, and protect themselves based on their habitat and geographical conditions.

🎯 Exam Tip: Emphasize the dynamic and continuous nature of adaptation, highlighting how it enables survival, reproduction, and protection within a specific environment.

Question d.
How are organisms classified?
Answer:
1. Different scientists have used different criteria and independently classified plants and animals.
2. A hierarchy is formed in the classification that starts with kingdom Animalia or kingdom Plantae, further groups and sub-groups are formed depending upon basic similarities and differences.
3. This is called the 'hierarchy of classification'.
4. Binomial nomenclature is used to identify each organism. Accordingly, a scientific name has been assigned to each organism.
5. It consists of two parts – first part is 'genus' and second 'species'.
6. All identified organisms have been assigned a binomial name as per the guidelines of the International code of Nomenclature. For e.g.

In simple words: Organisms are classified into a hierarchy starting from kingdoms, based on their similarities and differences. Each organism is also given a unique two-part scientific name (binomial nomenclature) consisting of its genus and species.

🎯 Exam Tip: When describing classification, explain the hierarchical system and the significance of binomial nomenclature with an example for clarity.

Activity:

Question 1.
Find out how the gradual adaptation from primitive man to modern man must have taken place.
Answer:
[No answer text provided in the original content for this activity.]
In simple words: This activity asks students to explore the evolutionary changes and adaptations that occurred over time, transforming primitive humans into modern humans.

🎯 Exam Tip: For activity-based questions without direct answers, demonstrate critical thinking by outlining the research process or key concepts involved in the topic.

Fill In The Blanks.

Question 1.
Leaves of some aquatic plants are ............. and ............. ike a ribbon.
Answer:
thin, slender
In simple words: The leaves of some aquatic plants are thin and slender like a ribbon, helping them adapt to water currents.

🎯 Exam Tip: Remember key terms for adaptations; thin and slender leaves help aquatic plants resist water flow.

Question 2.
............. in stems and ............. of aquatic plants are useful for floating in water.
Answer:
Air spaces, petioles
In simple words: Air spaces in stems and petioles help aquatic plants float on water.

🎯 Exam Tip: Understand how specialized structures like air spaces aid buoyancy for plants living in water.

Question 3.
Leaves of desert plants are modified into .............
Answer:
thorns
In simple words: Desert plants' leaves are modified into thorns to reduce water loss.

🎯 Exam Tip: Recognize thorns as a common adaptation in desert plants for minimizing transpiration.

Question 4.
The stems of desert plants are green as they perform ............. in the absence of leaves.
Answer:
photosynthesis
In simple words: Desert plant stems are green because they perform photosynthesis when leaves are absent.

🎯 Exam Tip: Note that in desert plants, the stem often takes over the function of photosynthesis due to leaf modification.

Question 5.
............. roots of grasses prevent soil erosion.
Answer:
Fibrous
In simple words: Fibrous roots in grasses help to prevent soil erosion by holding the soil firmly.

🎯 Exam Tip: Remember that fibrous roots are excellent for binding soil and preventing erosion, especially in grasslands.

Question 6.
Grasses in the ............. region are very tall.
Answer:
equatorial
In simple words: Grasses in the equatorial region tend to grow very tall due to favorable climate conditions.

🎯 Exam Tip: Associate tall grasses with the equatorial region, indicative of abundant rainfall and sunlight.

Question 7.
............. are found in hilly areas as well as plains.
Answer:
Vast meadows
In simple words: Vast meadows are expansive grasslands found in both hilly areas and plains.

🎯 Exam Tip: Understand that meadows can occur in diverse geographical settings, providing habitats for various species.

Question 8.
Plants need ............., ............. and ............. for growth.
Answer:
nitrogen, phosphorus, potassium
In simple words: Plants require essential nutrients like nitrogen, phosphorus, and potassium for healthy growth.

🎯 Exam Tip: Recall the primary macronutrients (NPK - Nitrogen, Phosphorus, Potassium) vital for plant development.

Question 9.
Dodder has ............. roots for absorbing nutrients from the host plant.
Answer:
haustorial (sucking)
In simple words: Dodder uses haustorial, or sucking, roots to absorb nutrients directly from its host plant.

🎯 Exam Tip: Identify haustorial roots as a parasitic adaptation that allows plants like dodder to extract resources from other plants.

Question 10.
Fungi do not have ............. so cannot perform photosynthesis.
Answer:
chlorophyll
In simple words: Fungi cannot perform photosynthesis because they lack chlorophyll.

🎯 Exam Tip: Understand that the absence of chlorophyll is the reason fungi are heterotrophic and cannot produce their own food.

Question 11.
Fish breathe with ............. instead of a nose.
Answer:
gills
In simple words: Fish breathe using gills, which extract oxygen from water, rather than having a nose like terrestrial animals.

🎯 Exam Tip: Gills are a primary adaptation for aquatic respiration; know their function for fish survival.

Question 12.
Fish have ............. within the body to help them to float.
Answer:
air bladders
In simple words: Fish possess air bladders inside their bodies, which help them control buoyancy and float in water.

🎯 Exam Tip: The air bladder (or swim bladder) is a crucial organ for fish to maintain their position in the water column without expending excess energy.

Question 13.
Frog and duck have ............. toes.
Answer:
webbed
In simple words: Both frogs and ducks have webbed toes, which are an adaptation for swimming in water.

🎯 Exam Tip: Webbed feet are a common adaptation for efficient movement in aquatic or semi-aquatic environments.

Question 14.
Tigers have ............. paws.
Answer:
padded
In simple words: Tigers have padded paws, which allow them to move silently while stalking prey.

🎯 Exam Tip: Padded paws are a predatory adaptation, enabling stealth and reducing noise during hunting.

Question 15.
Bats can fly with the help of ............. .
Answer:
patagium.
In simple words: Bats use a membrane called a patagium, stretched between their limbs, to achieve flight.

🎯 Exam Tip: Know the specific anatomical structures (like patagium) that enable unique animal abilities such as flight in bats.

Question 16.
Desert plants are either leafless or their leaves are like ........... or modified into ........... .
Answer:
needles, thorns
In simple words: Desert plants minimize water loss by being leafless or having leaves modified into needles or thorns.

🎯 Exam Tip: Understand how leaf modifications (leafless, needles, thorns) in desert plants are primarily for water conservation.

Question 17.
Spring like ............. on the stems of some climbers are examples of their adaptation.
Answer:
Tendrils
In simple words: Tendrils, which are spring-like structures on climbing plant stems, are an adaptation for support.

🎯 Exam Tip: Tendrils are a common adaptation in climbers, helping them attach to surfaces and grow upwards for better light exposure.

Question 18.
............. is not a sudden process, it is gradual and continuous.
Answer:
Adaptation
In simple words: Adaptation is a slow, continuous process, not a sudden change, allowing organisms to evolve and fit their environment over time.

🎯 Exam Tip: Emphasize that adaptation is an evolutionary process that unfolds over many generations, not instantaneously.

Question 19.
............. proposed the theory of the survival of the fittest.
Answer:
Charles Darwin
In simple words: Charles Darwin proposed the theory of the survival of the fittest, a key concept in natural selection.

🎯 Exam Tip: Correctly associate key scientific theories with their discoverers, such as Charles Darwin with 'survival of the fittest'.

Match The Columns:

Question 1.

In simple words: This matching exercise correctly links organisms with their characteristic environments or feeding habits, such as a cactus being a desert plant and a tiger being a carnivorous animal.

Answer:

🎯 Exam Tip: Accurately matching organisms to their adaptations or ecological roles requires a solid understanding of biological diversity and environmental contexts.

Question 2.

In simple words: This exercise matches common names of organisms with their correct scientific (binomial) names, which is fundamental for biological classification.

Answer:

🎯 Exam Tip: Memorizing the scientific names of common organisms is important for demonstrating knowledge of biological classification and taxonomy.

Name The Following:

Question 1.
Animals which live in desert in deep burrows.
Answer:
Rats, snakes, spiders, lizards
In simple words: Rats, snakes, spiders, and lizards are examples of animals that live in deep burrows in deserts to escape extreme temperatures.

🎯 Exam Tip: Burrows are a key behavioral adaptation for desert animals to avoid both high daytime temperatures and cold nights; remember specific examples.

Question 2.
Animals which have webbed feet.
Answer:
Frog, duck
In simple words: Frogs and ducks are common examples of animals that possess webbed feet for efficient swimming.

🎯 Exam Tip: Webbed feet are a distinct anatomical adaptation for aquatic or semi-aquatic lifestyles; recall animals that exhibit this feature.

Question 3.
Plants of snowy regions.
Answer:
Deodar, pine
In simple words: Deodar and pine are examples of plants specifically adapted to thrive in cold, snowy regions.

🎯 Exam Tip: Focus on coniferous trees like deodar and pine as typical flora of snowy, mountainous environments due to their conical shape and needle-like leaves.

Question 4.
Plants that eat insects.
Answer:
Drosera, venus flytrap, pitcher plant
In simple words: Drosera, Venus flytrap, and pitcher plants are examples of carnivorous plants that trap and digest insects to supplement their nutrient intake.

🎯 Exam Tip: Carnivorous plants have unique adaptations for capturing insects, usually found in nutrient-poor soils; remember a few key examples.

Question 5.
World Frog Protection Day.
Answer:
29th April
In simple words: World Frog Protection Day is observed on April 29th to raise awareness about the conservation of frogs.

🎯 Exam Tip: While not a science concept, knowing dates for environmental awareness days can show broader engagement with ecological topics.

Question 6.
2 parts of bionomial nomenclature.
Answer:
genus and species.
In simple words: Binomial nomenclature uses two parts, the genus and species, to give a unique scientific name to each organism.

🎯 Exam Tip: Clearly remember that binomial nomenclature always consists of the genus (capitalized) and species (lowercase) names.

Who Am I?

Question 1.
My leaves trap insects.
Answer:
Venus fly trap or pitcher plant.
In simple words: I am a carnivorous plant like the Venus flytrap or pitcher plant, known for my specialized leaves that capture insects.

🎯 Exam Tip: Identify insectivorous plants by their unique leaf adaptations designed for trapping prey.

Question 2.
I have waxy feathers and webbed feet.
Answer:
Duck
In simple words: I am a duck, characterized by my waxy feathers for waterproofing and webbed feet for swimming.

🎯 Exam Tip: Combine multiple adaptations to accurately identify an organism; waxy feathers and webbed feet strongly point to aquatic birds like ducks.

Question 3.
I breath through skin in water and through lungs on land.
Answer:
Frog
In simple words: I am a frog, an amphibian capable of breathing both through my skin in water and with lungs on land.

🎯 Exam Tip: Dual respiration (skin and lungs) is a key characteristic of amphibians like frogs, allowing them to live in both aquatic and terrestrial environments.

Question 4.
I have sucking roots through which I take nutrition from my host plant.
Answer:
Dodder (cuscuta)
In simple words: I am a dodder (Cuscuta), a parasitic plant that uses specialized sucking roots (haustoria) to extract nutrients from a host plant.

🎯 Exam Tip: Recognize parasitic plant adaptations, specifically haustorial roots, which allow them to draw sustenance from host organisms.

Question 5.
I have silvery white body with thick long hair
Answer:
Snow animals like polar bear.
In simple words: I am a snow animal, such as a polar bear, with a silvery-white body and thick, long hair for camouflage and insulation in cold environments.

🎯 Exam Tip: Connect physical traits like body color and hair thickness directly to adaptations for survival in snowy, cold habitats.

Question 6.
I have waxy broad leaves and air spaces in my stem.
Answer:
Lotus (or aquatic plants)
In simple words: I am a lotus, or an aquatic plant, featuring waxy, broad leaves and air spaces in my stem for buoyancy and water resistance.

🎯 Exam Tip: Understand that waxy leaves and air spaces are critical adaptations for aquatic plants to float and prevent waterlogging.

Question 7.
My Scientific name is Bos taurus.
Answer:
Cow
In simple words: My scientific name is Bos taurus, which refers to a domestic cow.

🎯 Exam Tip: Familiarize yourself with the scientific names of common animals, as they are part of biological classification.

Question 8.
I discovered Binomial nomenclature.
Answer:
Carl Linnaeus
In simple words: I am Carl Linnaeus, the scientist credited with developing the system of binomial nomenclature for classifying organisms.

🎯 Exam Tip: Remember Carl Linnaeus as the father of modern taxonomy and the inventor of binomial nomenclature.

Question 9.
I have special thin folds in between my forelegs and hind legs called patagium.
Answer:
Bat
In simple words: I am a bat, possessing a patagium, which is a thin membrane that forms my wings for flight.

🎯 Exam Tip: Patagium is a unique anatomical feature for flight in bats, distinguishing them from birds and insects.

Question 10.
I am mango, my genus is?
Answer:
Mangifera
In simple words: If I am a mango, my genus is Mangifera, as in Mangifera indica.

🎯 Exam Tip: Recall the genus part of the scientific name for common plants and animals; for mango, it's Mangifera.

Say Whether True Or False, Correct And Rewrite The False Statements:

Question 1.
Killing or harming frogs is prohibited by the Wild Life Protection Act.
Answer:
True
In simple words: It is true that the Wild Life Protection Act prohibits killing or harming frogs to protect biodiversity.

🎯 Exam Tip: Be aware of environmental protection laws and their role in conserving species like frogs.

Question 2.
Scientific name of jowar is Bos taurus.
Answer:
False. Scientific name of jowar is Sorghum bicolor
In simple words: This statement is false; the scientific name for jowar is Sorghum bicolor, not Bos taurus (which is for cow).

🎯 Exam Tip: Precisely recall the correct scientific names to avoid common factual errors; Bos taurus is a cow, while Sorghum bicolor is jowar.

Question 3.
Theory of natural selection was found by Charles Darwin.
Answer:
True
In simple words: It is true that Charles Darwin developed the theory of natural selection.

🎯 Exam Tip: Accurately attribute major scientific theories to their discoverers, such as Charles Darwin for natural selection.

Question 4.
T.V. Channels like National Geographic, Wild and Discovery show about the feeding habits of animals.
Answer:
True
In simple words: It is true that channels like National Geographic, Wild, and Discovery broadcast programs focused on animal feeding habits and wildlife.

🎯 Exam Tip: Acknowledge external resources like nature documentaries that provide educational content on animal behavior and ecology.

Question 5.
The spindle shaped body of birds maximizes the resistance of air while flying.
Answer:
False. The spindle shaped body of birds minimises the resistance of air while flying.
In simple words: This statement is false; the spindle-shaped body of birds is an adaptation that minimizes air resistance, helping them fly more efficiently.

🎯 Exam Tip: Understand that streamlined, spindle-shaped bodies are an adaptation to reduce drag and increase efficiency in fluid environments (air or water).

Question 6.
House lizard and monitor lizards have webbed toes.
Answer:
False. House lizard and monitor lizards have clawed toes.
In simple words: This statement is false; house and monitor lizards have clawed toes, which help them grip surfaces, unlike webbed toes used for swimming.

🎯 Exam Tip: Differentiate between adaptations like webbed toes (for swimming) and clawed toes (for gripping/climbing) when identifying animal features.

Complete The Given Table:

Question 1.

Answer:

In simple words: This table categorizes mango and human based on their biological classification hierarchy, showing similarities and differences at various taxonomic levels like Kingdom, Phylum, Class, Order, Family, Genus, and Species.

🎯 Exam Tip: Understanding this classification table is crucial for demonstrating knowledge of biological taxonomy and the systematic grouping of organisms.

Question 2.
Give one special adaptation or features of the following plant or animal to suit its habitat surrounding
Answer:

In simple words: This table lists various organisms and one key physical or structural adaptation they possess, which helps them survive and thrive in their specific natural environments.

🎯 Exam Tip: Remembering these specific adaptations for each organism can help illustrate your understanding of how living things interact with and survive in their habitats.

Who Is Lying?

Question 1.
Camel has thin skin and short eyelashes.
Answer:
Camel is lying - It has thick skin and long and thick eyelashes.
In simple words: The camel is incorrect; it actually has thick skin and long, thick eyelashes, which are adaptations to protect it from the harsh desert environment.

🎯 Exam Tip: Focus on recalling specific adaptations of animals to their environment, as these are common topics in questions about survival.

Answer In One Or Two Sentences:

Question 1.
What is called 'hierarchy of classification'?
Answer:
1. A hierarchy is formed in the classification that starts with kingdom Animalia or Kingdom Plantae, further groups and sub-groups are formed depending upon basic similarities and differences.
2. This is called the 'hierarchy of classification'.
In simple words: The hierarchy of classification is a structured system that groups organisms into kingdoms, phyla, classes, and other levels based on their shared characteristics, from broad to specific.

🎯 Exam Tip: Define 'hierarchy of classification' by mentioning its purpose (grouping based on similarities/differences) and starting points (kingdoms).

Question 2.
What theories were proprosed by Charles Darwin
Answer:
The theories of Charles Darwin are Theory of natural selection and theory of survival of the fittest.
In simple words: Charles Darwin proposed the theories of natural selection and survival of the fittest, explaining how species evolve over time through adaptation to their environment.

🎯 Exam Tip: Clearly state both theories - natural selection and survival of the fittest - when asked about Darwin's contributions.

Question 3.
Explain the terms Autotrophic and Parasitic
Answer:
1. Plants which are able to produce their own food with the help of the process of photosynthesis are called autotrophic plants eg. All green plants.
2. Plants which are not able to produce their own food but depend upon other plants for their nutrition are called parasitic plants They are leafless and non green in colour eg. Dodder (cuscuta). They have haustorial (sucking) roots for absorbing nutrients from the host plant.
In simple words: Autotrophic organisms, like green plants, make their own food through photosynthesis, while parasitic organisms, such as dodder, obtain nutrients by living on and feeding from a host organism.

🎯 Exam Tip: When explaining terms, provide a clear definition and a relevant example for each to score full marks.

Give Scientific Reasons:

Question 1.
Leaves of some aquatic plants are thin and slender like a ribbon.
Answer:
Leaves of some aquatic plants are thin and slender like a ribbon because this shape helps them to withstand fast currents of water.
In simple words: Aquatic plants have thin, ribbon-like leaves to reduce resistance and prevent damage from strong water currents.

🎯 Exam Tip: Relate the specific adaptation (leaf shape) directly to its functional benefit in the aquatic environment.

Question 2.
Some aquatic plants have air spaces in stems.
Answer:
Some aquatic plants have air spaces in stems because air spaces help the plants to float on water.
In simple words: Air spaces in the stems of aquatic plants provide buoyancy, helping them to float and access sunlight at the water's surface.

🎯 Exam Tip: Highlight the primary function of air spaces in aquatic plants, which is flotation for light absorption.

Question 3.
Desert plants have thorns.
Answer:
1. Desert plants have thorns because in deserts, due to scarcity of water these plants are either leafless or their leaves are like small needles or modified into thorns.
2. They lose very little water by evaporation due to little surface area. This helps plants to survive in desert.
In simple words: Desert plants have thorns instead of leaves to minimize water loss through evaporation, an essential adaptation for survival in dry environments.

🎯 Exam Tip: Explain both the structural change (thorns instead of leaves) and its benefit (reduced water loss) for a complete answer.

Question 4.
Desert plants have green stem.
Answer:
Desert plants have green stem because green stem performs photosynthesis in the absence of leaves.
In simple words: Desert plants have green stems because, lacking leaves, their stems have evolved to perform photosynthesis and produce food.

🎯 Exam Tip: Connect the green color of the stem directly to its role in photosynthesis, especially when leaves are absent or modified.

Question 5.
Desert plants have strong roots.
Answer:
Desert plants have strong roots so they can penetrate deep into the soil in search of water.
In simple words: Desert plants develop strong, deep roots to efficiently reach and absorb scarce water sources far beneath the soil surface.

🎯 Exam Tip: Emphasize that strong roots in desert plants are primarily for accessing deep water reserves.

Question 6.
Deodar tree is conical in shape.
Answer:
Deodar tree grows in snowy region and conical shape of the tree doesn't allow snow to accumulate on the tree and thus protect the tree from snow.
In simple words: The conical shape of Deodar trees helps snow to slide off easily, preventing accumulation and protecting the tree from damage in snowy regions.

🎯 Exam Tip: When explaining tree shapes in snowy regions, focus on how the shape facilitates snow shedding and prevents breakage.

Question 7.
Pine tree has thick bark.
Answer:
Pine tree grows in snowy region where it is extremely cold and its thick bark helps the tree to withstand the cold.
In simple words: Pine trees have thick bark to provide insulation and protect them from the extremely cold temperatures common in snowy regions.

🎯 Exam Tip: Link the thick bark of pine trees directly to its protective function against harsh cold climates.

Question 8.
Plants in forest grow tall.
Answer:
In forest region variety of trees, shrubs and herbs are found. These plants compete amongst themselves for sunlight. Hence trees grow tall to get sunlight.
In simple words: Forest plants grow tall to compete effectively for sunlight, which is often limited due to the dense canopy of other vegetation.

🎯 Exam Tip: The key reason for tall growth in forests is competition for sunlight; clearly state this competitive advantage.

Question 9.
Cuscuta has haustorial roots.
Answer:
1. Cuscuta is a parasitic plant. It is leafless and cannot prepare food on its own.
2. So to get food haustorial (sucking) roots penetrate up to the conducting vessels of the host plant to absorb water and food, the Cuscuta has haustorial roots.
In simple words: Cuscuta, a parasitic plant without leaves, uses haustorial roots to penetrate host plants and absorb essential water and nutrients, as it cannot produce its own food.

🎯 Exam Tip: Emphasize Cuscuta's parasitic nature and how haustorial roots are essential for nutrient absorption from a host.

Question 10.
Fungi have root-like fibers.
Answer:
1. Fungi are parasitic.
2. They do not have chlorophyll and cannot perform photosynthesis.
3. So these root-like fibers help to absorb the food from the starchy foodstuffs like bhakri and bread.
In simple words: Fungi, being parasitic and lacking chlorophyll, have root-like fibers to absorb nutrients from their food sources, such as starchy items.

🎯 Exam Tip: Connect the absence of chlorophyll in fungi to their parasitic nature and the function of root-like fibers in absorbing food.

Question 11.
Pitcher plant eats insects.
Answer:
1. Pitcher plant grows in a soil where nitrogen, phosphorous and potassium are very less. But the plant needs these for the growth.
2. So to fulfill the need for nitrogen, pitcher plant consumes insects.
In simple words: Pitcher plants eat insects to supplement their diet with essential nitrogen, phosphorus, and potassium, which are scarce in the poor soils where they grow.

🎯 Exam Tip: Explain that insectivory in pitcher plants is a nutritional adaptation to compensate for nutrient-poor soil, specifically nitrogen deficiency.

Question 12.
Duck and frog have webbed feet.
Answer:
When duck and frog are in water at that time the webbed feet act as oars and help them to swim in water.
In simple words: Ducks and frogs have webbed feet that function like oars, enabling them to swim efficiently in water.

🎯 Exam Tip: The primary function of webbed feet for aquatic animals is enhanced swimming capability; mention their action as 'oars'.

Question 13.
Frogs can swim easily in water.
Answer:
Frogs have webbed toes, slippery, smooth skin and triangular head. This helps the frog to swim easily through water.
In simple words: Frogs swim easily due to webbed toes, smooth slippery skin, and a triangular head, all of which reduce drag and aid propulsion in water.

🎯 Exam Tip: List multiple adaptations (webbed feet, skin, head shape) that collectively contribute to a frog's efficient swimming.

Question 14.
Tiger has sharp and pointed canine teeth.
Answer:
Tiger is a carnivorous animal. So the sharp and pointed canine teeth help the tiger to tear the prey and eat.
In simple words: Tigers, as carnivores, possess sharp and pointed canine teeth specifically adapted for tearing flesh from their prey.

🎯 Exam Tip: Connect the tiger's carnivorous diet directly to the function of its sharp canine teeth for tearing meat.

Question 15.
Blackbuck has eyes on either side of the head.
Answer:
Blackbuck is a herbivore animal and eyes on either side of the head gives them wide angle vision which helps to protect themselves from predators.
In simple words: Blackbucks, being herbivores, have eyes on the sides of their head to provide a wide field of vision, helping them detect and escape predators.

🎯 Exam Tip: Distinguish between predatory and prey animals' eye placement and their respective advantages for survival.

Question 16.
Tigers have padded paws.
Answer:
Tigers are carnivorous animals. So these padded paws enable them to silently stalk their prey and capture it easily.
In simple words: Tigers have padded paws, which allow them to move silently and stealthily, essential for stalking and ambushing their prey as carnivores.

🎯 Exam Tip: Emphasize the role of padded paws in silent movement, which is critical for a predator's hunting strategy.

Question 17.
The eyes of predatory carnivores are located in the front of their head.
Answer:
The eyes of predatory carnivores are located in the front of their head because it helps them to spot their prey from a long distance.
In simple words: Predatory carnivores have forward-facing eyes to provide excellent depth perception, allowing them to accurately track and capture prey from a distance.

🎯 Exam Tip: Explain that front-facing eyes give binocular vision and depth perception, crucial for predators to accurately locate prey.

Question 18.
Camel can live in desert.
Answer:
1. Camel can live in desert because it has thick skin to prevent loss of water from the body. Their legs are long with flat and cushioned soles.
2. The nostrils are protected by folds of skin. The eyelashes are long and thick so these adaptations enable Camels to live in desert easily.
In simple words: Camels can thrive in the desert due to adaptations like thick skin to prevent water loss, long legs with cushioned soles for walking on sand, and protected nostrils and eyelashes for sand and heat protection.

🎯 Exam Tip: When explaining camel adaptations, list multiple features—skin, legs, soles, nostrils, eyelashes—and how each contributes to desert survival.

Question 19.
White fox has white body colour.
Answer:
1. White fox lives in snowy region which throughout the year is covered with snow.
2. White colour of fox matches with the snow so it gets camouflaged in snow and it can save itself from predators.
In simple words: The white fur of the white fox provides camouflage in snowy environments, helping it hide from predators and ambush prey.

🎯 Exam Tip: Link the white fur color directly to camouflage and its dual benefit for both hiding from predators and hunting prey.

Question 20.
Birds can fly in the air.
Answer:
1. Birds can fly in the air because the spindle shaped body minimises the resistance of air while flying.
2. Their hollow bones, body covering of feathers and forelegs being modified into wings, their body being light in weight, all these factors make the birds adapted to fly in the air.
In simple words: Birds are adapted for flight with a spindle-shaped body to reduce air resistance, hollow bones for lightness, feathers for lift and propulsion, and forelegs modified into wings, collectively enabling them to fly.

🎯 Exam Tip: Provide a comprehensive answer by listing multiple adaptations—body shape, bones, feathers, wings—that enable flight in birds.

Can You Tell?

Answer The Following Questions:

Question 1.
Arc the plants and animals from Kashmir and Rajasthan of the same type? Can you elaborate on any differences between the two?
Answer:
Plants and animals from Kashmir and Rajasthan are of different types.
Differences in plants:
1. Plants of Kashmir, which is a snowy region, are conical in shape due to their sloping branches.
2. This shape prevents the snow accumulation on the tree and the thick bark helps the tree to withstand the cold.
3. But the plants of Rajasthan, which is a desert region, are either leafless or their leaves are small, needle shaped or have been modified into thorns. So the loss of water can be reduced
4. The stem stores water and food so they are fleshy. The stem performs photosynthesis in the absence of leaves.
Differences in animals:
1. Animals of Kashmir have thick hair and white or silver body colour camouflaged with snow. This helps them to get protection in snowy region.
2. The animals of Rajasthan have long legs with flat and cushioned soles.
3. The nostrils are protected by folds of skin. The eyelashes are long and thick. It gives protection from sand and heat.
In simple words: Plants and animals from Kashmir (cold, snowy) and Rajasthan (hot, desert) are distinct due to diverse adaptations for their climates; Kashmiri organisms are adapted for cold with conical shapes and thick fur, while Rajasthani organisms are adapted for heat and water scarcity with thorns and specialized body features.

🎯 Exam Tip: Clearly categorize differences into 'plants' and 'animals' and for each, provide specific adaptations relevant to their respective cold/snowy or hot/desert environments.

Question 2.
In what way are sloping branches useful to plants in a snowy region?
Answer:
In a snowy region sloping branches of a plant gives conical shape to the tree and it doesn't allow snow to accumulate on tree inspite of heavy snowfall and thus protect the tree from severe cold and snow.
In simple words: Sloping branches in snowy regions give trees a conical shape, which prevents heavy snow from accumulating and causing damage, thereby protecting the tree from severe cold.

🎯 Exam Tip: Focus on how the conical shape and sloping branches prevent snow accumulation, a key survival mechanism in cold environments.

Question 3.
What is the main difference between vehicles on the road and aeroplanes?
Answer:
The two main differences between vehicles on the road and aeroplanes are:
1. aeroplanes have wings whereas vehicles on the road do not have wings.
2. The body of aeroplanes are spindle shaped and the body of vehicles on the road depends on the number of wheels they have.
In simple words: The main differences are that aeroplanes possess wings for flight and have a streamlined, spindle shape to minimize air resistance, whereas road vehicles lack wings and their body design is influenced by the number of wheels.

🎯 Exam Tip: Highlight structural differences like wings and body shape (spindle vs. wheel-dependent) as key distinguishing features.

Use Your Brain Power!

Answer The Following Questions:

Question 1.
Why does water trickle off lotus leaves?
Answer:
1. Water trickles off lotus leaves because it is coated with waxy covering on it.
2. It is one of the adaptations of aquatic plants to survive in water without getting wet and rot or sink to the bottom.
In simple words: Water trickles off lotus leaves because they have a waxy coating, an adaptation that prevents them from getting wet, rotting, or sinking in water.

🎯 Exam Tip: Focus on the waxy coating as the primary reason and its benefit in preventing water absorption and decay for aquatic plants.

Question 2.
Why don't the leaves of lotus plants rotinwatei?
Answer:
leaves of these plants do not rot in water because it is covered with waxy coating on it so that they do not get wet.
In simple words: Lotus leaves do not rot in water because their waxy coating repels water, keeping them dry and protected from decay.

🎯 Exam Tip: The waxy coating is the key factor; explain how it prevents water absorption and, consequently, rotting.

Question 3.
Why are roots of lotus plants short and fibrous?
Answer: -
1. These plants grow in water so the roots do not need to go deep down in search of water. Their roots are not anchored in the soil.
2. So their roots are short and fibrous.
In simple words: Lotus plants have short, fibrous roots because they grow in water and do not need to anchor deeply or search for water, unlike terrestrial plants.

🎯 Exam Tip: Contrast the needs of aquatic plants with terrestrial ones to explain why deep anchoring roots are unnecessary for lotus plants.

Question 4.
The lotus stalk has holes or air spaces?
Answer:
1. The air spaces in stems and petioles of aquatic plants are useful for making them float in water and also to prevent them from rotting
2. Hence, the lotus stalk has holes or air spaces.
In simple words: Lotus stalks have holes or air spaces that provide buoyancy, helping the plant float, and also aid in preventing rot by promoting aeration within the tissues.

🎯 Exam Tip: The air spaces in lotus stalks serve two main purposes: flotation and aeration, both crucial for aquatic survival.

Answer In Detail:

Question 1.
Explain the Darwin's theory of evolution.
Answer:
Charles Darwin, a biologist suggested two principles in his theory of evolution.
1. Theory of survival of the fittest: He said that only those organisms are likely to survive which can best adapt themselves to a changing environment. This is called the theory of survival of the fittest.
2. Theory of 'Natural selection': If an organism is born with a new beneficial characteristic and is able to survive, this change is preserved in the next generation. This is called the theory of 'natural selection'.
In simple words: Charles Darwin's theory of evolution rests on two principles: 'survival of the fittest,' where adaptable organisms thrive, and 'natural selection,' where beneficial traits passed to future generations lead to gradual evolutionary change.

🎯 Exam Tip: Clearly differentiate between the 'survival of the fittest' (individual adaptation for survival) and 'natural selection' (inheritance of beneficial traits over generations).

Diagram Based Questions:

Question 1.
Draw a neat labelled diagram of fish and answer the following questions.
Answer:

ℹ️ चित्र व्याख्या (Diagram Explanation): यह एक मछली का साफ-सुथरा नामांकित चित्र है। इसमें मछली के शरीर के प्रमुख अंग जैसे फिन्स (पंख), गिल्स (गलफड़े), और स्केल्स (शल्क) स्पष्ट रूप से दिखाए गए हैं। फिन्स मछली को तैरने और दिशा बदलने में मदद करते हैं, गिल्स पानी में घुली ऑक्सीजन को अवशोषित करने के लिए होते हैं, और स्केल्स उसके शरीर को सुरक्षा प्रदान करते हैं।

Question a.
Why do fish have a body tapering towards both its ends?
Answer:
Fish have its body tapering towards its ends, to allow them to swim with least resistance in water.
In simple words: Fish have a streamlined, tapering body shape to reduce water resistance, allowing them to swim efficiently and with minimal effort.

🎯 Exam Tip: The tapering body shape of fish is a classic example of streamlining, directly related to reducing drag for efficient movement in water.

Question b.
Why do Fish have transparent eyelids.
Answer:
The transparent eyelids of fish protect the eyes from the substance in the water
In simple words: Fish have transparent eyelids to protect their eyes from particles and substances in the water while still allowing them to see.

🎯 Exam Tip: The transparency of fish eyelids is key; it combines protection with maintaining vision underwater.

Question c.
How are they able to float?
Answer:
Fish have air bladders within their body which help them to float.
In simple words: Fish use an air bladder, also known as a swim bladder, to control their buoyancy and effortlessly float at various depths in the water.

🎯 Exam Tip: The air bladder is the primary organ for buoyancy control in most fish; its function for floating should be clearly stated.

Question 2.
Observe the diagram and answer the questions.
Answer:

ℹ️ चित्र व्याख्या (Diagram Explanation): यह एक ऊंट का स्पष्ट चित्र है। ऊंट का शरीर रेगिस्तानी जीवन शैली के लिए अनुकूलित है, जिसमें एक कूबड़ (hump) दिखाई दे रहा है जो वसा और पानी को संग्रहित करता है। इसके पैर लंबे और गद्देदार तलवों वाले हैं, जो इसे गर्म रेत पर आसानी से चलने में मदद करते हैं। यह चित्र ऊंट के शुष्क और गर्म वातावरण में जीवित रहने की क्षमता को दर्शाता है।

Question a.
What habitat does this camel live in?
Answer:
Camel lives in desert habitats or in areas where there is scarcity of water.
In simple words: Camels live in desert environments where water is scarce, adapted to survive extreme heat and dryness.

🎯 Exam Tip: Clearly identify the desert as the primary habitat for camels, linking it to their adaptations for water scarcity.

Question b.
State any 2 of its body adaptations to survive in desert?
Answer:
1. Thick skin to prevent loss of water from the body
2. The eyelashes are long and thin
3. Their legs are long and flat with cushioned soles
In simple words: Two key adaptations of a camel for desert survival are its thick skin to reduce water loss and its long legs with cushioned soles, which help it navigate hot sand without sinking.

🎯 Exam Tip: When asked for specific adaptations, pick distinct physical features and explain their direct benefit in the desert environment.

Question c.
How does a camel protect itself from sand storms or winds carrying sand?
Answer:
Camels have nostrils protected by folds of skin and long thick eyelashes to prevent entry of fir dust and sand into its nose and eyes.
In simple words: Camels protect themselves from sandstorms with nostrils that can close due to folds of skin and long, thick eyelashes that shield their eyes from sand and dust.

🎯 Exam Tip: Focus on the specific features—nostril folds and long eyelashes—and their protective function against sand during storms.

Paragraph Based Questions:

Compare And Contrast:

Question 1.
Compare the lotus plant to the Acacia plant and Hibiscus plant.
Answer:

In simple words: Lotus (aquatic) has air spaces in stems and waxy leaves for flotation and water repulsion; Hibiscus (terrestrial) has no air spaces and thin leaves; Acacia (desert) has fleshy stems for water storage and tiny or thorn-modified leaves to reduce water loss.

🎯 Exam Tip: When comparing plants, highlight adaptations related to their specific habitats: buoyancy for aquatic, typical structure for terrestrial, and water conservation for desert plants.

Question 2.
What is the difference between the plants given in the pictures. Give 2 points of difference taking into consideration their adaptations with their surroundings.
Answer:

ℹ️ चित्र व्याख्या (Diagram Explanation): इस चित्र में तीन अलग-अलग पौधे दिखाए गए हैं: (A) कमल का पौधा, (B) कैक्टस का पौधा, और (C) देवदार का पेड़। कमल एक जलीय पौधा है जो पानी में उगता है, कैक्टस एक रेगिस्तानी पौधा है जो शुष्क वातावरण में पाया जाता है, और देवदार एक पर्वतीय वृक्ष है जो बर्फीले क्षेत्रों में पनपता है। यह चित्र विभिन्न आवासों के लिए पौधों के विविध अनुकूलन को दर्शाता है।

In simple words: Cactus (desert) has fleshy green stems and thorns for water storage and protection; Lotus (aquatic) has stems with air spaces and broad waxy leaves for flotation and water repulsion; Deodar (snowy) is conical with needle-shaped leaves to shed snow and withstand cold.

🎯 Exam Tip: When comparing these three plants, focus on their primary adaptations for their distinct environments: water conservation (cactus), buoyancy/water resistance (lotus), and snow shedding/cold tolerance (deodar).