Maharashtra Board Class 7 Science Chapter 4 Nutrition in Living Organisms Solutions

Question 1. Classify according to food-type. Tiger, cow, vulture, bacteria, deer, goat, human, fungus, lion, sparrow, buffalo, frog, cockroach, tick.
Answer:
• Carnivores: tiger, Lion
• Herbivores: cow, deer, goat, buffalo
• Scavengers: vulture
• Decomposers: fungus, bacteria
• Granivores: sparrow
• Insectivores: frog Parasitic: tick
• Omnivores: human, cockroach
In simple words: Organisms are classified based on their dietary habits into groups like carnivores, herbivores, omnivores, scavengers, decomposers, granivores, and insectivores, reflecting what they eat.

🎯 Exam Tip: Remember specific examples for each food-type classification, as this is a common way to test understanding of ecological roles.

Nutrition In Living Organisms Class 7 Exercise Match The Pairs

Question 1. Match the pairs.

Answer:

In simple words: This match-the-pairs exercise connects different types of nutritional strategies (parasitic, saprophytic, symbiotic) with specific plant examples.

🎯 Exam Tip: Understanding the unique characteristics of each nutritional type (e.g., parasitic dependence, saprophytic decay, symbiotic mutualism) is crucial for accurate matching.

3. Answer The Following Questions In Your Words.

Question a. Why do living organisms need nutrition?
Answer: Living organisms need nutrition due to the following:
(a) To supply the energy required for doing work,
(b) For growth and development of the body,
(c) To replace the damaged cells and repair tissues,
(d) To fight diseases.
In simple words: Living organisms require nutrition for essential life processes such as obtaining energy, growing, repairing body tissues, and defending against illnesses.

🎯 Exam Tip: When listing reasons, clearly articulate each point to ensure full marks; a well-structured answer shows comprehensive understanding.

Question b. Explain the process of production of food in plants.
Answer: 1. Green plants can produce their own food. With the help of sunlight and chlorophyll, plants make their own food in their leaves, using water and nutrients from the soil and carbon dioxide from the air. 2. This process is called as photosynthesis. In this process plants give out oxygen and take in carbon dioxide. \[ 6CO_2 + 6H_2O \xrightarrow{\text{Sunlight}} C_6H_{12}O_6 + 6O_2 \]
In simple words: Plants produce their food through photosynthesis, converting carbon dioxide and water into glucose and oxygen using sunlight energy and chlorophyll.

🎯 Exam Tip: Remember the balanced chemical equation for photosynthesis and the key raw materials and products, as this is a fundamental concept.

Question c. What is meant by parasitic plants? Name their different types with examples of each.
Answer: The plants that grow on the body of other plants to obtain food are called as parasitic plants.
There are two types of parasitic plants:
• Holoparasites: e.g. Rafflesiaceae
• Hemiparasites: e.g. Loranthaceae
In simple words: Parasitic plants obtain nutrients from other plants, and they are categorized as holoparasites (fully dependent) or hemiparasites (partially dependent, still photosynthesize).

🎯 Exam Tip: Distinguishing between holoparasites and hemiparasites by their degree of dependence and providing clear examples will earn you full credit.

Question d. Explain the various steps of nutrition in animals.
Answer: Steps of nutrition in animals are as follows:
1. Ingestion: Food is taken into the body.
2. Digestion: Conversion of food into simple soluble forms.
3. Absorption: Transfer of soluble food to the blood.
4. Assimilation: Utilization of absorbed food by cells and tissues for energy production, growth and repair.
5. Egestion: Removal of waste products and undigested food from body.
In simple words: Animal nutrition involves a sequence of five steps: ingesting food, digesting it into simpler forms, absorbing nutrients, assimilating them for body functions, and finally egesting waste.

🎯 Exam Tip: Memorize the five stages of animal nutrition in sequence, and be prepared to provide a brief definition for each stage.

Question e. Name some unicellular organisms in which all life processes take place within their unicellular body.
Answer: Unicellular organisms like amoeba, euglena, paramoecium in which all life processes take place within their unicellular body.
In simple words: Amoeba, Euglena, and Paramoecium are examples of unicellular organisms where all vital life functions occur within a single cell.

🎯 Exam Tip: When asked for examples, listing at least two distinct organisms demonstrates a good grasp of the concept.

4. Give Reasons.

Question a. Insectivorous plants are attractively coloured.
Answer: 1. Insectivorous plants generally grow in soil or water deficient in nitrogen compounds. 2. The plant body of the Drosera burmanii has a flower like appearance. It grows close to the ground. Even its leaves are attractively pink or red in colour with hairs at the margin. 3. Droplets of a sticky substances found on tips of the hairs attract insects. 4. These plants consume insects to fulfill their need for nitrogen. To attract the insects these plants are attractively coloured.
In simple words: Insectivorous plants are brightly colored to attract insects, which they then capture and consume to supplement their nitrogen intake, especially in nutrient-poor soils.

🎯 Exam Tip: When explaining adaptations, always connect the feature (e.g., color) to its functional benefit (e.g., insect attraction for nitrogen acquisition).

Question b. Butterflies have a long tube-like proboscis.
Answer: Holozoic mode of nutrition means the feeding of solid and liquid food by animals. Butterflies live on nectar from flowers. Therefore to suck the nectar from flowers, they have a long tube-like structure called proboscis.
In simple words: Butterflies possess a long, tube-like proboscis, an adaptation that allows them to efficiently suck nectar from deep within flowers, fulfilling their nutritional needs.

🎯 Exam Tip: Relate the anatomical feature (proboscis) directly to the specific feeding behavior (sucking nectar) and the organism's diet for a complete explanation.

5. Prepare And Complete The Flowchart According To Type Of Nutrition.

Question a. Prepare and complete the flowchart according to type of nutrition.
Answer:
ℹ️ चित्र व्याख्या (Diagram Explanation): यह एक प्रवाह चार्ट है जो पोषण के प्रकारों को दर्शाता है। यह पोषण को पौधों और जानवरों में विभाजित करता है। पौधों के पोषण को स्वपोषी और विषमपोषी में बांटा गया है, जिसमें विषमपोषी में कीटभक्षी शामिल हैं। जानवरों के पोषण को विषमपोषी, मृतजीवी, परजीवी, बाह्यपरजीवी और अंतःपरजीवी में वर्गीकृत किया गया है।
In simple words: The flowchart illustrates the classification of nutrition, differentiating between plant and animal nutrition, and further subdividing them into specific modes like autotrophic, heterotrophic, parasitic, saprophytic, insectivorous, ectoparasitic, and endoparasitic.

🎯 Exam Tip: For flowcharts, ensure all major categories and sub-categories are logically arranged and clearly labelled to demonstrate understanding of hierarchical classification.

6. Think And Answer.

Question a. We prepare a variety of foodstuffs and dishes at home. Are we then autotrophic organisms?
Answer: 1. We prepare a variety of foodstuffs and dishes at home but we are not autotrophic organisms. 2. In autotrophic organisms they have chlorophyll in their body and food is prepared here with help of sunlight, water and CO2 for the organisms. 3. But the food which we prepare at home is not generated in our body.
In simple words: Humans are not autotrophic because, despite preparing food, we cannot produce our own food from simple inorganic substances like plants do using chlorophyll and sunlight.

🎯 Exam Tip: Clearly define autotrophic nutrition by its core mechanism (self-synthesis using chlorophyll, sunlight, water, CO2) to explain why humans don't fit the category.

Question b. Which organisms are greater in number - autotrophs or heterotrophs? Why?
Answer: 1. Autotrophs have chlorophyll in the cell and here the organic food is prepared using sunlight, water and CO2. 2. They do not depend on any other organism for survival. 3. But the heterotrophs depend on autotrophs and other organisms for survival. Hence autotrophs are more in number than heterotrophs.
In simple words: Autotrophs are more numerous than heterotrophs because they are primary producers, forming the base of almost all food chains, supporting themselves and all heterotrophs.

🎯 Exam Tip: Emphasize the role of autotrophs as producers and their independence for food production, which logically explains their greater numbers in an ecosystem.

Question c. The number of heterotrophs found in desert regions is smaller. However, they are found in greater numbers in the sea. Why is this so?
Answer: 1. In desert region due to scarcity of water and excess heat, very few cactus are found as autotrophs compared to sea. As autotrophs are less, number of heterotrophs dependent on autotrophs are smaller. 2. Whereas in sea due to greater numbers of autotrophs, greater number of heterotrophs are found.
In simple words: Deserts have fewer heterotrophs due to limited autotrophs caused by harsh conditions, while the sea supports abundant heterotrophs because it has a vast population of autotrophs like phytoplankton.

🎯 Exam Tip: When comparing ecosystems, focus on the availability of primary producers (autotrophs) as the limiting factor for the population size of consumers (heterotrophs).

Question d. What damage or harm do ectoparasitic and endoparasitic animals cause?
Answer: 1. Ectoparasitic animals suck the blood of the animal on which it remains and endoparasitic animals get readymade food from the body of animal in which it remain. 2. This way both the parasites make the animal weak by sucking their blood or by eating prepared food from them.
In simple words: Ectoparasites weaken their hosts by feeding on external substances like blood, while endoparasites harm hosts by consuming internal tissues or nutrients, both modes depleting the host's resources and health.

🎯 Exam Tip: Clearly differentiate the location of harm (external vs. internal) and the method of nutrient acquisition for ecto- and endoparasites to explain their respective damages.

Question e. Why is plant food not produced in any other parts of the plant except the green ones?
Answer: Plant food is not produced in any other parts of the plant except the green ones because only green part contains chlorophyll and chlorophyll is very necessary for the production of food.
In simple words: Plant food is primarily produced in green parts because only these sections contain chlorophyll, the pigment essential for absorbing sunlight energy during photosynthesis.

🎯 Exam Tip: The key to this answer is emphasizing the presence of chlorophyll, directly linking it to the process of photosynthesis and food production.

Question 1. Many heterotrophic organisms live on one and the same plant. Observe one such plant in your neighborhood and find out about the heterotrophs that depend upon it for their food. Observe and make flotes about other organisms that use these heterotrophs as their food.

Question 2. Prepare a Power point presentation on the topic 'Nutrition in Living Organisms'.

Fill In The Blanks.

Question 1. Leaves have microscopic openings called ................
Answer: Stomata
In simple words: Leaves have tiny pores called stomata that facilitate gas exchange for photosynthesis and respiration.

🎯 Exam Tip: "Stomata" is a key term; remember its plural form and primary function in gas exchange.

Question 2. In the process of photosynthesis plants take in ................ and ................ gas is given out.
Answer: Carbondioxide, oxygen
In simple words: During photosynthesis, plants absorb carbon dioxide and release oxygen as a byproduct.

🎯 Exam Tip: Knowing the primary gas consumed (carbon dioxide) and the gas released (oxygen) during photosynthesis is fundamental.

Question 3. The ................ transports minerals and water from roots to all aerial parts of the plant.
Answer: xylem
In simple words: Xylem is the plant tissue responsible for transporting water and minerals from the roots up to the rest of the plant.

🎯 Exam Tip: Remember that xylem transports water and minerals, distinguishing its role from phloem.

Question 4. The ................ transports the food from the leaves to other parts of the plant.
Answer: phloem
In simple words: Phloem is the plant tissue that carries synthesized food, primarily sugars, from the leaves to other growing and storage parts of the plant.

🎯 Exam Tip: Distinguish phloem's role in food transport from xylem's role in water and mineral transport.

Question 5. Plants produce ............ by the process of photosynthesis.
Answer: Carbohydrates
In simple words: Through photosynthesis, plants produce carbohydrates (sugars) as their primary form of energy and stored food.

🎯 Exam Tip: "Carbohydrates" is the main product of photosynthesis that serves as food for the plant.

Question 6. ................ are made from carbon, hydrogen, oxygen.
Answer: Carbohydrates
In simple words: Carbohydrates are organic molecules composed of carbon, hydrogen, and oxygen atoms.

🎯 Exam Tip: Knowing the basic elemental composition of major biomolecules like carbohydrates is important.

Question 7. ................ are made from carbon, hydrogen and oxygen and nitrogen.
Answer: proteins
In simple words: Proteins are complex molecules primarily composed of carbon, hydrogen, oxygen, and crucially, nitrogen, which differentiates them from carbohydrates and fats.

🎯 Exam Tip: The presence of nitrogen is a key distinguishing feature of proteins compared to carbohydrates and fats.

Question 8. ................ plants contain rhizobium micro-organisms.
Answer: leguminous
In simple words: Leguminous plants, such as peas and beans, form a symbiotic relationship with Rhizobium bacteria in their root nodules, which fix atmospheric nitrogen.

🎯 Exam Tip: Connect "leguminous plants" directly with "Rhizobium" and "nitrogen fixation" as these are core concepts in nutrient cycling.

Question 9. Micro-organisms like ................ are present in soil.
Answer: azotobacter
In simple words: Azotobacter is a type of free-living microorganism found in soil that helps in nitrogen fixation, converting atmospheric nitrogen into a usable form for plants.

🎯 Exam Tip: Azotobacter is an important example of a non-symbiotic nitrogen-fixing bacterium in soil.

Question 10. Lichen is of a symbiosis between ......... and ............. .
Answer: algae, fungi
In simple words: A lichen represents a symbiotic partnership where algae perform photosynthesis and fungi provide structure and absorb water and minerals.

🎯 Exam Tip: Remember the two key organisms (algae and fungi) and the mutualistic nature of their relationship in a lichen.

Question 11. The scientist ................ identified Drosera plant in Sri Lanka in 1737.
Answer: Johannes Burman
In simple words: Johannes Burman was the scientist who first identified the Drosera plant in Sri Lanka in 1737.

🎯 Exam Tip: This is a specific factual recall question; ensure you remember the name associated with the discovery.

Question 12. Fungi like mushroom and yeast are ................
Answer: saprophytes
In simple words: Mushrooms and yeast are examples of saprophytic fungi, meaning they obtain nutrients by decomposing dead organic matter.

🎯 Exam Tip: Identify mushrooms and yeast as saprophytes, linking their nutrition to the decomposition of dead material.

Question 13. Removal of waste products and undigested food from the body is called ................
Answer: Egestion
In simple words: Egestion is the biological process of expelling undigested food and waste materials from the body.

🎯 Exam Tip: Differentiate egestion (removal of undigested food) from excretion (removal of metabolic waste).

Question 14. Amoeba moves with the help of ................
Answer: pseudopodia
In simple words: Amoeba moves and engulfs food using temporary, arm-like extensions of its cytoplasm called pseudopodia.

🎯 Exam Tip: Pseudopodia are characteristic structures for locomotion and feeding in amoebas.

Question 15. Butterflies suck food with a tube like ................
Answer: proboscis
In simple words: Butterflies use their long, coiled, tube-like mouthpart, called a proboscis, to draw nectar from flowers.

🎯 Exam Tip: The proboscis is a specialized feeding appendage found in butterflies and moths.

Question 16. The ................ or ................ is an ant eating animal found in India.
Answer: bobcat, udmanjar
In simple words: The bobcat or udmanjar is an animal native to India known for its diet of ants.

🎯 Exam Tip: Knowing regional examples of animals and their diets helps broaden your understanding of biodiversity.

Question 17. Seed eating animals are called ................
Answer: granivores
In simple words: Animals that primarily feed on seeds are known as granivores.

🎯 Exam Tip: "Granivores" is the specific term for seed-eating animals; remember this vocabulary.

Question 18. Fruit eating animals are called ................
Answer: frugivores
In simple words: Animals whose diet mainly consists of fruits are termed frugivores.

🎯 Exam Tip: "Frugivores" refers to animals that primarily consume fruits; add this to your ecological vocabulary.

Question 19. Animals that obtain their food from both plants and animals are called ................
Answer: Omnivores
In simple words: Omnivores are animals that consume a diverse diet, including both plant and animal matter.

🎯 Exam Tip: Omnivores represent a flexible feeding strategy, consuming both plant and animal sources, unlike herbivores or carnivores.

Question 20. Roundworms are known as ................
Answer: endoparasites
In simple words: Roundworms are classified as endoparasites because they live inside the body of their host organisms, feeding on their internal tissues or nutrients.

🎯 Exam Tip: Remember that "endoparasites" are parasites that live *inside* the host's body.

Match The Column:

Question 1. Match the column.

Answer:

In simple words: This table matches various nutritional roles or feeding habits (endoparasite, ectoparasite, seed-eating, fruit-eating, scavenger, omnivore) with their corresponding examples.

🎯 Exam Tip: For matching questions, a strong understanding of both definitions and specific examples for each category is essential to ensure accurate pairing.

The False Statements.

Question 1. Bed bug is an example of endoparasitic nutrition.
Answer: False, Bed bug is an example of ectoparasitic nutrition
In simple words: The statement is false; bed bugs are ectoparasites because they live on the external surface of their host and feed.

🎯 Exam Tip: Clearly differentiate between "endo-" (inside) and "ecto-" (outside) when classifying parasites, and always provide the correct statement if the original is false.

Question 2. Spider shows saprozoic nutrition.
Answer: True
In simple words: Spiders exhibit saprozoic nutrition, meaning they digest their prey externally before ingesting the liquid nutrients.

🎯 Exam Tip: While spiders are typically predators, the term "saprozoic" relates to absorption of pre-digested food, which aligns with how some spiders consume liquefied prey.

Question 3. The anteater is found in India.
Answer: False. The anteater is found in Central and South America
In simple words: The statement is false; anteaters are native to Central and South America, not India.

🎯 Exam Tip: Factual questions about animal distribution require precise geographical knowledge; be careful not to confuse similar-looking animals from different regions.

Question 4. Yellowing of leaves occur due to deficiency of iron.
Answer: True
In simple words: Yellowing of leaves, known as chlorosis, is indeed a symptom of iron deficiency in plants.

🎯 Exam Tip: Associate specific plant symptoms (like yellowing leaves) with the deficiency of essential micronutrients (like iron).

Question 5. Mushroom is used in making bread.
Answer: False. Yeast is used in making bread
In simple words: The statement is false; yeast, a type of fungus, is used in bread making for fermentation, not mushrooms.

🎯 Exam Tip: Understand the specific roles of different fungi; yeast is crucial for fermentation in baking, while mushrooms have other uses.

Question 6. Cuscuta is completely a parasitic plant.
Answer: True
In simple words: Cuscuta, also known as dodder, is a holoparasite, meaning it is entirely dependent on its host plant for nutrition and lacks chlorophyll.

🎯 Exam Tip: Remember that Cuscuta is a classic example of a holoparasite due to its complete nutritional dependence on a host.

Question 7. The nitrogen dioxide dissolves in rainwater and is converted into nitric acid.
Answer: True
In simple words: Nitrogen dioxide reacts with water in the atmosphere to form nitric acid, contributing to acid rain and providing nitrates to the soil.

🎯 Exam Tip: Understand the atmospheric reactions involving nitrogen oxides, specifically their conversion to nitric acid in rainwater, which impacts soil fertility and causes acid rain.

Question 8. Micro-organism Rhizobium is found in soil.
Answer: False. Micro-organism Azotobacter is found in soil.
In simple words: While Rhizobium forms a symbiotic relationship within plant roots, Azotobacter is a free-living microorganism commonly found in the soil.

🎯 Exam Tip: Distinguish between symbiotic nitrogen fixers like Rhizobium (in root nodules) and free-living ones like Azotobacter (in soil).

Question 9. Fixation of nitrogen occurs by biological and atmospheric methods.
Answer: True
In simple words: Nitrogen fixation, the conversion of atmospheric nitrogen into usable forms, occurs naturally through both biological processes (by microorganisms) and atmospheric events (like lightning).

🎯 Exam Tip: Remember the two primary natural methods of nitrogen fixation: biological (microbes) and atmospheric (lightning).

Question 10. The chloroplasts present in the leaves contain chlorophyll.
Answer: True
In simple words: Chloroplasts are organelles within plant cells, especially in leaves, that house chlorophyll, the green pigment vital for photosynthesis.

🎯 Exam Tip: Understand the relationship: leaves contain cells, cells contain chloroplasts, and chloroplasts contain chlorophyll.

Question 11. Decomposers obtain their food from living organisms.
Answer: False, They obtain their food by decomposing the dead bodies of organisms or other materials
In simple words: The statement is false; decomposers obtain nutrients by breaking down dead organic matter, not from living organisms.

🎯 Exam Tip: Clearly define decomposers as organisms that feed on dead and decaying matter, playing a crucial role in nutrient recycling.

Question 12. Carbondixode is given out during the process of photosynthesis.
Answer: False, Oxygen is given out during the process of photosynthesis
In simple words: The statement is false; carbon dioxide is *taken in* during photosynthesis, while oxygen is *released*.

🎯 Exam Tip: Accurately recall the inputs and outputs of photosynthesis: CO2 and water are inputs, while glucose and O2 are outputs.

Question 13. Phloem transports the food from leaves to other parts of the plant.
Answer: True
In simple words: Phloem is the vascular tissue responsible for translocating sugars and other organic nutrients, produced during photosynthesis in the leaves, to all other parts of the plant.

🎯 Exam Tip: Remember that phloem's primary function is the transport of food (sugars), complementing xylem's water transport.

Question 14. Carbohydrates are made up of carbon, hydrogen oxygen and nitrogen.
Answer: False, Protein are made up of carbon, hydrogen, Oxygen and nitrogen.
In simple words: The statement is false; carbohydrates are composed only of carbon, hydrogen, and oxygen, whereas proteins additionally contain nitrogen.

🎯 Exam Tip: Be precise with the elemental composition of biomolecules; the presence of nitrogen is a defining characteristic of proteins, not carbohydrates.

Give Scientific Reasons.

Question 1. Micro-organisms like Rhizobium are useful.
Answer: 1. Rhizobium micro-organisms are useful because plants cannot take gaseous nitrogen from air. 2. These micro-organisms absorb atmospheric nitrogen and convert it into its nitrate, a compound which is useful for plant.
In simple words: Rhizobium microorganisms are beneficial because they convert atmospheric nitrogen, which plants cannot directly use, into nitrates, a form that plants can absorb and utilize for growth.

🎯 Exam Tip: Explain both *why* Rhizobium is needed (plants can't use gaseous nitrogen) and *what* it does (converts nitrogen to nitrates).

Question 2. Lichen is an example of a symbiotic nutrition.
Answer: Lichen is a symbiosis between algae and fungi in which fungi provides water, minerals, as well as shelter to algae and in return the algae Master Key General Science (Std. 7), provide food to the fungi. So Lichen, is an example of symbiotic nutrition.
In simple words: Lichen is a symbiotic nutrition example because it's a mutualistic partnership where fungi offer structural support and absorb water/minerals, while algae perform photosynthesis to provide food for both organisms.

🎯 Exam Tip: Define symbiosis (mutual benefit) and specify the roles of both partners (algae and fungi) in the lichen relationship.

Question 3. Drosera burmanii is an insectivorous plant.
Answer: Drosera burmanii grows in a soil which has nitrogen deficiency. It feeds upon insects to obtain nitrogen, so it is an insectivorous plant.
In simple words: Drosera burmanii is insectivorous because it grows in nitrogen-deficient soils and supplements its nutrient intake by catching and digesting insects to acquire essential nitrogen.

🎯 Exam Tip: The reason for insectivory in plants is almost always to obtain nitrogen from environments where it is scarce in the soil.

Question 4. Human is an omnivore.
Answer: Humans obtain their food from both, plants and animals so human is an omnivore.
In simple words: Humans are classified as omnivores because their diet naturally includes both plant-based foods and animal products.

🎯 Exam Tip: The definition of an omnivore is straightforward: an organism that consumes both plant and animal matter.

Question 5. Tapeworm is an endoparasite.
Answer: Tapeworm lives inside the body of other animals and obtain its food. So tapeworm is an endoparasite.
In simple words: Tapeworms are endoparasites because they reside within the digestive system of their animal hosts, absorbing nutrients directly from the host's digested food.

🎯 Exam Tip: Remember that endoparasites, like tapeworms, live *inside* the host's body, absorbing nutrients directly from its internal environment.

Question 1. Classify the types of nutrients.
Answer: There are two types of nutrients.
1. Nutrients like carbohydrates, proteins and fats are required in large quantity. These are macro-nutrients.
2. Minerals and vitamins are required in very small quantity. They are called micro-nutrients.
In simple words: Nutrients are essential substances needed for growth and energy. They are broadly classified into macronutrients (like carbs, proteins, fats needed in large amounts) and micronutrients (like minerals, vitamins needed in small amounts).

🎯 Exam Tip: Understanding the classification of nutrients is fundamental to comprehending nutritional requirements for all living organisms.

Question 2. Explain the types of nutrition.
Answer: There are two types of nutrition.
1. Some organisms can produce their own food and thus nourish themselves. This is called autotrophic nutrition.
2. Some organisms depend on other organisms, plants and animals for their food. This is called heterotrophic nutrition.
In simple words: Nutrition is how organisms obtain food. Autotrophic nutrition is when organisms make their own food (like plants), while heterotrophic nutrition is when organisms rely on other living things for food (like animals).

🎯 Exam Tip: Clearly defining autotrophic and heterotrophic nutrition, along with relevant examples, is crucial for full marks.

Question 3. Write differences between xylem and phloem.
Answer:

In simple words: Xylem and phloem are plant tissues that transport substances. Xylem carries water and minerals from roots to the rest of the plant, while phloem carries prepared food (glucose) from leaves to other parts for use or storage.

🎯 Exam Tip: Presenting differences in a table format makes the answer clear and easy to evaluate. Remember the specific functions of each tissue.

Question 4. What is chemosynthesis? Which plants produce their food by chemosynthesis?
Answer:
1. Chemosynthesis is the biological conversion of one or more carbon-containing molecules and nutrients into organic matter.
2. It uses the oxidation of inorganic compounds or methane as a source of energy rather than sunlight.
3. Sulphur bacteria and nitrosomonas produce their food by chemosynthesis.
In simple words: Chemosynthesis is a process where organisms, like certain bacteria, produce their own food using energy from chemical reactions (oxidizing inorganic compounds) instead of sunlight.

🎯 Exam Tip: Differentiate chemosynthesis from photosynthesis by highlighting the energy source (chemical reactions vs. sunlight).

Question 5. Name the micro-organisms which help in biological fixation of nitrogen. How?
Answer: Two different types of micro-organisms can bring about biological nitrogen fixation.
1. Root-nodules of leguminous plants contain the micro-organism rhizobium. These micro-organisms absorb atmospheric nitrogen and convert if into its nitrate, a compound.
2. Micro-organisms like azotobacter are present in soil. They also convert atmospheric nitrogen into nitrates.
In simple words: Rhizobium (in leguminous plant roots) and Azotobacter (in soil) are microorganisms that convert atmospheric nitrogen into usable nitrates, enriching the soil for plants.

🎯 Exam Tip: Naming the specific microorganisms and explaining their role in converting atmospheric nitrogen to nitrates are key points for this answer.

Question 6. What is symbiotic nutrition? Give one example of it.
Answer:
1. Two or more than two different types of plant live together to fulfill their needs of nutrition, protection, support etc. with each other's help. This type of nutrition is called symbiotic nutrition.
2. e.g. Lichen is an example of symbiosis between algae and fungi.
In simple words: Symbiotic nutrition is a relationship where two or more different organisms live together and benefit from each other, sharing resources like nutrition, protection, and support. Lichens, formed by algae and fungi, are a classic example.

🎯 Exam Tip: Defining symbiotic nutrition and providing a clear, common example like lichens demonstrates a good understanding of the concept.

Question 7. Write about Drosera burmanii.
Answer:
1. It is art insectivorous plant.
2. The scientist Johannes Burman identified this plant in Sri Lanka in 1737. Hence, the plant is named after him.
3. It grows close to the ground.
4. Its leaves are attractively pink or red in colour with hairs at the margin.
5. Droplets of a sticky substance found at the tips of the hairs attract insects.
6. It grows in a place where deficiency of nitrogen in the soil. To get nitrogen for its growth, it eats insects.
In simple words: Drosera burmanii is an insectivorous plant with attractive, sticky, pink/red leaves that trap insects to obtain nitrogen, as it grows in nitrogen-deficient soil.

🎯 Exam Tip: Highlight its insectivorous nature, unique appearance (sticky, colored leaves), and the reason for its insect-eating habit (nitrogen deficiency).

Question 8. What are called saprophytic plants? Give Examples.
Answer: Plants which obtain the food from dead and decaying bodies of other organisms are called saprophytic plants e.g. Yeast and mushrooms.
In simple words: Saprophytic plants are those that get their food from dead and decaying organic matter, such as yeast and mushrooms.

🎯 Exam Tip: Remember that saprophytes are decomposers and provide examples that clearly illustrate this type of nutrition.

Question 9. Classify the animals according to the type of food they eat. microbes, vulture, monkey, tiger, lion, goat, cow, buffalo, crow, hyena, human, chimpanzee
Answer:
• Herbivores: goat, cow, buffalo.
• Carnivores: tiger, lion
• Omnivores: monkey, human, chimpanzee
• Scavengers: vulture, crow, hyena
• Decomposers: microbes
In simple words: Animals are classified by diet into herbivores (plant-eaters), carnivores (meat-eaters), omnivores (both), scavengers (dead animals), and decomposers (break down dead matter).

🎯 Exam Tip: Provide clear and accurate examples for each dietary classification to demonstrate comprehensive knowledge.

Explain the terms:

Question. 1. Herbivores: Animals that depend on plants only for their food are called Herbivores.
Answer:
In simple words: Herbivores are animals that consume only plants for their diet.

🎯 Exam Tip: A concise definition linking "herbivore" directly to "plant-eating" is essential.

Question. 2. Carnivores: Animals that depend on other animals for their food are called Carnivores.
Answer:
In simple words: Carnivores are animals whose diet consists entirely of other animals.

🎯 Exam Tip: Define carnivores clearly as animals that prey on other animals for food.

Question. 3. Granivores: Animals that eat grains (seed) are called Granivores.
Answer:
In simple words: Granivores are animals that primarily feed on grains and seeds.

🎯 Exam Tip: Specify "grains" or "seeds" as the primary food source for granivores.

Question. 4. Frugivores: Animals that eat fruits are called frugivores.
Answer:
In simple words: Frugivores are animals whose diet is mainly composed of fruits.

🎯 Exam Tip: A direct link between "frugivore" and "fruit-eating" is the core of the definition.

Question. 5. Omnivores: Animals that obtain their food from both plants and animals are called omnivores.
Answer:
In simple words: Omnivores are animals that consume both plant and animal matter for food.

🎯 Exam Tip: The key characteristic of omnivores is their mixed diet of both plant and animal sources.

Question. 6. Scavengers: Animals that obtain their food from dead bodies of animals are called Scavengers.
Answer:
In simple words: Scavengers are animals that feed on the remains of dead animals.

🎯 Exam Tip: Emphasize that scavengers consume dead organic matter, particularly animal carcasses.

Question. 7. Decomposers: Microbes which obtain their food by decomposing the dead bodies of organisms or other materials are called decomposers.
Answer:
In simple words: Decomposers are microorganisms that break down dead organisms and waste materials, recycling nutrients back into the ecosystem.

🎯 Exam Tip: Focus on the role of decomposers in breaking down dead organic matter and their microbial nature.

Question. 8. Ectoparasitic nutrition: Some animals live on the body surface of other animals and obtain their food by sucking their blood. This is called ectoparasitic nutrition.
Answer:
In simple words: Ectoparasitic nutrition involves animals living on the outside surface of another organism (host) and feeding on its blood or body fluids.

🎯 Exam Tip: The location (external) and method of feeding (sucking blood/fluids) are critical details for ectoparasitic nutrition.

Question. 9. Endoparasitic nutrition: Some animals live inside the body of other animals and obtain their food. This is called endoparasitic nutrition.
Answer:
In simple words: Endoparasitic nutrition occurs when animals live inside the body of another organism (host) and derive their food from it.

🎯 Exam Tip: Highlight the internal dwelling location within the host for endoparasitic nutrition.

Question. 10. Symbiotic nutrition: In some cases, two or more than two different types of plants live together to fulfill their needs of nutrition, protection, support etc. with each other's help. This type of nutrition is called symbiotic nutrition.
Answer:
In simple words: Symbiotic nutrition describes a mutually beneficial relationship where different plants live together, helping each other meet various needs like nutrition and protection.

🎯 Exam Tip: Stress the "mutual benefit" and "living together" aspects in the definition of symbiotic nutrition.

Write the role of different nutrients like nitrogen, phosphorus, potassium,magnesium, Iron, manganese and zinc and effects of their deficiency on plants.

Question 1. Write the role of different nutrients like nitrogen, phosphorus, potassium, magnesium, Iron, manganese and zinc and effects of their deficiency on plants.
Answer: Role of nutrients and effects of their deficiency on plants:

In simple words: Each nutrient plays a specific role in plant growth, from forming essential structures like chlorophyll and proteins (Nitrogen, Magnesium, Iron) to aiding energy conversion (Phosphorus) and metabolic processes (Potassium, Manganese, Zinc). Deficiencies lead to visible symptoms like stunted growth, yellowing leaves, and reduced productivity.

🎯 Exam Tip: Creating a structured table with 'Nutrient', 'Function', and 'Deficiency Effects' columns ensures clarity and covers all aspects of the question comprehensively.

Can you tell?

Answer the following question:

Question 1. How does ingestion occur in unicellular animals like amoeba?
Answer:
ℹ️ चित्र व्याख्या (Diagram Explanation): यह चित्र अमीबा में भोजन ग्रहण करने की प्रक्रिया को दर्शाता है। इसमें दिखाया गया है कि एक भोजन का कण अमीबा के पास आता है और अमीबा अपने स्यूडोपोडिया (अस्थायी पैर) का उपयोग करके उसे चारों ओर से घेर लेता है, अंततः उसे अपने शरीर के अंदर निगल लेता है।
1. Amoeba does not have organs like hands and mouth.
2. It is a unicellular animal. It can take in food through any part of the surface of its unicellular body.
3. It surrounds the food particle from all sides to take it into the cell.
4. After that it digests the food with the help of different enzymes.
5. Undigested food is left behind as the amoeba moves further with the help of pseudopodia.
6. In unicellular animals like amoeba, euglena, paramoecium,. etc. all the steps of nutrition occur within their unicellular body.
In simple words: Amoeba ingests food by extending temporary projections called pseudopodia to surround and engulf food particles, a process known as phagocytosis. The food is then digested inside its single cell.

🎯 Exam Tip: Emphasize the role of pseudopodia and the engulfing mechanism (phagocytosis) when describing ingestion in amoeba.

Question 2. How do plants produce their own food?
Answer: Green plants produce their own food with the help of sunlight, chlorophyll, water, nutrients from soil and carbon dioxide from the air. This process is called as photosynthesis
ℹ️ चित्र व्याख्या (Diagram Explanation): यह चित्र प्रकाश संश्लेषण की प्रक्रिया को रासायनिक समीकरण के रूप में दर्शाता है। यह दिखाता है कि कार्बन डाइऑक्साइड और पानी सूर्य के प्रकाश और क्लोरोफिल की उपस्थिति में मिलकर ग्लूकोज (भोजन) और ऑक्सीजन बनाते हैं, जो पौधों द्वारा भोजन उत्पादन की प्रक्रिया है। \[ 6CO₂ + 6H₂O \xrightarrow{\text{Sunlight}} C_6H_{12}O_6 + 6O_2 \]
In simple words: Plants produce their own food through photosynthesis, using sunlight, chlorophyll, water, carbon dioxide, and soil nutrients to create glucose (food) and oxygen.

🎯 Exam Tip: The answer must include the key components (sunlight, chlorophyll, water, CO2) and the products (glucose, oxygen) of photosynthesis, along with the correct chemical equation.

Use your brain power!

Answer the following questions:

Question 1. Write the uses of yeast and mushrooms.
Answer: Yeast is used in fermentation processes and making bread. Mushrooms are a rich source of vitamins and iron.
In simple words: Yeast is vital for fermentation in bread making and alcohol production, while mushrooms are a nutritious food source rich in vitamins and iron.

🎯 Exam Tip: Clearly state specific uses for both yeast (fermentation, bread) and mushrooms (nutritional value, vitamins, iron).

Question 2.i Which part of the loranthus plant carries out photosynthesis?
Answer: Leaves of the loranthus plant carries out photosynthesis.
In simple words: The leaves of the loranthus plant are responsible for carrying out photosynthesis.

🎯 Exam Tip: Identify the specific plant organ (leaves) responsible for photosynthesis in Loranthus.

Question 2.ii From where do they obtain minerals and water?
Answer: They obtain water and minerals from the xylem and phloem of the other host plant.
In simple words: Loranthus obtains water and minerals by tapping into the xylem and phloem of its host plant.

🎯 Exam Tip: State that Loranthus gets water and minerals from the host plant's vascular tissues (xylem and phloem).

Question 2.iii Why is loranthus known as a partially parasitic plant?
Answer: Loranthus is known as partially parasitic plant because it does photosynthesis with the help of leaves but only for water and minerals it depends on other plants.
In simple words: Loranthus is a partially parasitic plant because it performs its own photosynthesis using its leaves but relies on a host plant for water and mineral supply.

🎯 Exam Tip: The key reason for "partially parasitic" is its ability to photosynthesize combined with its dependence on a host for water and minerals.

Question 3. Why does the pitcher plant feed on insects even though it produces food by photosynthesis?
Answer: Pitcher plants grow in a place where soil has deficiency of nitrogen compounds so to fulfill the need of nitrogen they feed on insects.
In simple words: Pitcher plants, despite performing photosynthesis, consume insects to supplement their nitrogen intake because they grow in nitrogen-deficient soils.

🎯 Exam Tip: The critical point is that insect consumption by pitcher plants is to compensate for nitrogen deficiency in their habitat.

Observe the diagram and answer the following questions.

ℹ️ चित्र व्याख्या (Diagram Explanation): यह चित्र प्रकाश संश्लेषण की प्रक्रिया को दर्शाता है। इसमें एक पौधा दिखाया गया है जो सूर्य के प्रकाश और कार्बन डाइऑक्साइड को ग्रहण करता है और ऑक्सीजन छोड़ता है। पौधे की जड़ें पानी और खनिजों को मिट्टी से अवशोषित करती हैं, तथा पत्तियों में क्लोरोफिल की उपस्थिति में यह प्रक्रिया होती है।

Question a. Name the process shown in the picture.
Answer: The process shown is photosynthesis.
In simple words: The diagram illustrates the process of photosynthesis.

🎯 Exam Tip: Directly identify the biological process depicted in the diagram.

Question b. Which type of plants use the above process for their nutrition?
Answer: Autotrophic plants (green plants) use the above process for their nutrition.
In simple words: Autotrophic plants, also known as green plants, use photosynthesis to produce their own food.

🎯 Exam Tip: Link photosynthesis specifically to autotrophic or green plants.

Question c. What is the pigment in the leaf that helps in the above process?
Answer: Chlorophyll
In simple words: Chlorophyll is the green pigment in leaves essential for photosynthesis.

🎯 Exam Tip: Name the specific pigment responsible for absorbing light energy in photosynthesis.

Question d. Give the chemical equation of the above process?
Answer:
\[ 6CO₂ + 6H₂O \xrightarrow{\text{Chlorophyll}} C_6H_{12}O_6 + 6O_2 \]
In simple words: The chemical equation for photosynthesis shows carbon dioxide and water reacting in the presence of sunlight and chlorophyll to produce glucose and oxygen.

🎯 Exam Tip: Accurately writing the balanced chemical equation for photosynthesis, including the reactants, products, and conditions (sunlight, chlorophyll), is crucial.

Question e. What is the importance of this process to living things?
Answer: Photosynthesis helps the plants to prepare their own food and also store it in their plant bodies. Animals depend upon this stored food for their nutrition. During photosynthesis, oxygen is given out which is important for all living organisms for respiration.
In simple words: Photosynthesis is vital because it provides food for plants (and indirectly for all animals), and it releases oxygen, which is essential for respiration in most living organisms.

🎯 Exam Tip: Focus on the dual importance: food production (energy source for the ecosystem) and oxygen release (essential for aerobic respiration).

Observe the diagram and answer the following questions.

ℹ️ चित्र व्याख्या (Diagram Explanation): यह चित्र एक फलदार पौधे की जड़ों को दर्शाता है, जिसमें छोटे-छोटे नोड्यूल स्पष्ट रूप से दिखाई दे रहे हैं। ये नोड्यूल राइजोबियम जैसे सूक्ष्मजीवों का घर होते हैं जो नाइट्रोजन स्थिरीकरण में महत्वपूर्ण भूमिका निभाते हैं, जिससे मिट्टी की उर्वरता बढ़ती है।

Question a. What is shown in the picture?
Answer: Roots of leguminous plants having root nodules.
In simple words: The picture displays the roots of a leguminous plant, which are characterized by the presence of small root nodules.

🎯 Exam Tip: Accurately identify the key feature shown in the diagram: root nodules on leguminous plants.

Question b. What is the importance of these types of plants?
Answer: These types of plants help to provide nitrogen to the soil.
In simple words: Leguminous plants are important because they enrich the soil with nitrogen through nitrogen fixation.

🎯 Exam Tip: Focus on the primary ecological benefit: their contribution to soil nitrogen content.

Question c. What is the process called?
Answer: Biological Nitrogen fixation
In simple words: The process occurring in these plant roots is called Biological Nitrogen Fixation.

🎯 Exam Tip: State the exact name of the biological process involved with these roots.

Question d. Explain the process.
Answer: Root nodules of leguminous plants contain Rhizobium micro-organisms. These micro-organisms convert atmospheric nitrogen into nitrates. Thus the soil becomes rich in nitrogen.
In simple words: In biological nitrogen fixation, Rhizobium bacteria residing in the root nodules of leguminous plants convert atmospheric nitrogen gas into nitrates, a form usable by plants, thereby enriching the soil.

🎯 Exam Tip: Explain the symbiotic relationship, naming Rhizobium bacteria and detailing how they convert atmospheric nitrogen into nitrates within the root nodules.