PSEB Notes

This PSEB 6th Class Science Notes Chapter 7 Getting to Know Plants will help you in revision during exams.

PSEB 6th Class Science Notes Chapter 7 Getting to Know Plants

→ We have a large variety of plants around us. These differ in size, shape, colour of leaves, flowers, etc.

→ Plants around us are usually grouped inter herbs, shrubs, and trees

→ Herbs are small-sized plants with soft green stems which generally lack branches.

→ Shrubs are medium-sized plants with hard stems and branched near the base or near the ground. Trees are tall and long with strong stems called trunks.

→ Parts of a plant consist of two types of system – root system and shoot system.

→ The root system is the underground part of the plant. It anchors the plant to the soil.

→ Roots absorb water and minerals from the soil.

→ The shoot system is the portion of the plant above the ground.

→ Two types of roots are taproots and fibrous roots.

→ Stem conducts water to leaves and other parts of the plant.

→ Stem conducts water to leaves and other parts of the plant.

→ The green colour of leaves is due to the presence of a pigment called chlorophyll.

→ Leaves perform photosynthesis and transpiration.

→ The leaf is made up of two parts-petiole and lamina.

→ The lines on the leaf lamina are called veins and in the centre is called midrib.

→ Venation is of two types: Parallel venation and Reticulate venation.

→ A flower is the reproductive part of a plant.

→ The flower has sepals, petals, stamens, and pistils.

→ Stamen is the male reproductive organ.

→ The pistil is the female reproductive organ.

→ Creepers: Herbs having a weak stem that cannot stand upright and spread on the ground are called creepers.

→ Climbers: Plants having a weak stem that cannot stand erect and take support of nearby objects to climb up are called climbers.

→ Taproot: The root which has a main root and branched smaller roots is called the taproot.

→ Fibrous root: This root has no main root. It is like a bundle of thread-like growth. All roots seem similar and are known as fibrous roots.

→ Weeds: The unwanted plants grown with the main crop are weeds.

→ Venation: The design made by veins in a leaf is called venation.

→ Parallel Venation: When the lines/veins are parallel to one another then it is known as parallel venation.

→ Reticulate Venation: When there is a network of veins then the venation is reticulate venation.

→ Herbs: The plants with small size, green and tender stems are known as herbs.

→ Shrubs: Plants having strong stem branched at the base are known as shrubs.

→ Trees: Trees are tall-sized plants in which the main stem is hard, broad, and thick at the base, and branches are found on the upper part.

→ Trunk: The main step of a tree which is woody, hard, broad, and thick at the base, and bare branches is known as the trunk.

→ Photosynthesis: The process by which plants prepare food using carbon dioxide and water in the presence of chlorophyll and sunlight.

→ Transpiration: Loss of water vapour from plants through stomata.

This PSEB 6th Class Science Notes Chapter 6 Changes Around Us will help you in revision during exams.

PSEB 6th Class Science Notes Chapter 6 Changes Around Us

→ Change is an act by which a thing becomes different from its previous one.

→ We see many changes around us and every change is important in a positive or negative way.

→ Changes can be grouped together by finding similarities and differences between them.

→ All the changes can be broadly divided into two types i.e. natural and manmade.

→ Changes that occur in nature and do not require our involvement are called natural changes. These are never ending changes.

→ Examples of natural changes include melting of snow, falling of leaves from trees, etc.

→ Changes occurring due to the efforts of human beings are called artificial or manmade changes.

→ Examples of manmade changes include preparing chapattis from wheat flour, cooking vegetables, etc.

→ Based on the speed, we can classify changes into two categories. These are slow changes and fast changes.

→ Slow changes are those which take more time to happen. For example, growing of tree, a baby becoming an adult, etc.

→ Fast changes are those that happen very fast. For example, burning of match sticks, bursting of crackers, etc.

→ Out of all the changes around us, only a few changes can be reversed. These are called reversible changes.

→ The changes which cannot be reversed are called irreversible changes.

→ A change in a substance is called reversible if we can get the substance in its original form by changing the conditions.

→ For example, ice changes to water on melting and water can be changed into ice by cooling, is a reversible change.

→ A change in a substance is called irreversible if we cannot get the substance in its original form by changing the conditions.

→ For example, roti once prepared on Tawa, cannot be changed back to dough again.

→ Some changes are periodic whereas others are non-periodic.

→ Changes that are repeated after regular intervals of time are called periodic changes.

→ For example, change of day and night, swinging of pendulum of a clock, the beating of heart, change of seasons.

→ Changes that are not repeated after a regular interval of time are called non-periodic changes.

→ For example, the occurrence of earthquakes, the occurrence of rain, etc.

→ We have classified changes into physical and chemical changes.

→ Any temporary change in which no new substance is formed and the chemical composition of the original substance remains the same is known as physical change.

→ During physical changes, physical properties like colour, shape, size, state, etc. may change. Therefore, we can say that Physical change is a reversible change.

→ Any permanent change in which new substances are formed. These have physical and chemical properties completely different from those of the original substance.

→ Physical changes are mostly reversible in nature whereas chemical changes are mostly irreversible changes.

→ Expansion and contraction are physical changes that are very useful in our daily life.

→ In the expansion the dimensions of the substance increase and in contraction the dimensions of the substance decrease.

→ Change: An act by which a thing becomes different from its previous one.

→ Natural changes: Changes that are occurring naturally and are never-ending are called natural changes.

→ Manmade changes: Changes that are occurring due to the efforts of human beings are called manmade changes.

→ Periodic change: Changes that are repeated after regular intervals of time are called periodic changes.

→ For example, change of day and night, swinging of pendulum of a clock, beating of heart, change of seasons.

→ Non-periodic changes: Changes that are not repeated after regular intervals of time are called non-periodic changes.

→ For example, the occurrence of earthquakes, the occurrence of rain, etc.

→ Reversible change: The changes which take place in a substance and can be reversed to their original state are called Reversible changes.

→ Irreversible change: The changes which cannot be reversed to the original substances are called Irreversible changes.

→ Physical Change: Physical change is a temporary change in which no new substance is formed and the chemical composition of the original substance remains the same.

→ Chemical change: Chemical change is a permanent change in which new substances are formed whose physical and chemical properties are completely different from those of the original substance.

→ Expansion: When a substance increases its size on heating then the change is called expansion.

→ Thermal expansion: When the expansion is due to an increase in temperature it is called thermal expansion.

→ Contraction: When a substance decreases its size on cooling then the change, is called contraction.

→ Evaporation: When a liquid changes into the gaseous form on heating or on decreasing pressure then the process is known as evaporation.

→ Melting: When a solid changes into liquid form on heating or on increasing pressure then the process is known as melting.

This PSEB 6th Class Science Notes Chapter 5 Separation of Substances will help you in revision during exams.

PSEB 6th Class Science Notes Chapter 5 Separation of Substances

→ Substances around us can be pure substances or impure substances. Impure substances are also known as mixtures.

→ A pure substance is made up of only one type of atom or molecule, e.g. water. It has definite composition and properties.

→ Some mixtures have some desired substances and undesired substances.

→ We must separate undesired substances from desired substances.

→ The process of separating different substances from a mixture is known as separation.

→ The separation must be done if it has undesired substances. This is because undesired substances in the mixture can be harmful to us.

→ Separation is important in those cases where we need a particular component in a pure state.

→ We have many methods for separating components of a mixture.

→ These are based upon differences in the properties of substances present in the mixture.

→ Different methods of separation are Hand-picking, Threshing, Winnowing, Sieving, Sedimentation, Decantation, Filtration, Evaporation, etc.

→ Hand-picking is used to separate the components of a mixture if we can see these with f naked eye and these are large in size.

→ The combine is used for both the harvesting and threshing process.

→ Threshing is the separation of grains from the chaff. It can be done using any one method out of the three i.e.

• manual
• with the help of Animals
• using machines

→ Winnowing is a method to separate heavier and lighter components of a mixture by wind or by blowing air.

→ Methods like decantation, sedimentation, filtration, evaporation are used to separate mixtures of solids and liquids.

→ The process of settling down heavier, insoluble particles from a mixture is called sedimentation.

→ The substance that settles at the bottom is called sediment.

→ This method is used to separate insoluble heavier particles from a liquid.

→ The process of transferring the clear liquid without disturbing sediment is known as decantation.

→ The process of separating an insoluble solid from a liquid bypassing the liquid through a filter paper or muslin cloth is known as filtration.

→ The process of separating differently sized particles of a mixture using a sieve is called sieving.

→ The process of converting a liquid into its vapours by heating is called evaporation.

→ Sometimes we can or need more than one method for separating components of a mixture.

→ When a mixture of two or more substances appears like a single substance or pure substance it is called a solution.

→ In a solution, the substance present in a larger amount is called the solvent and the substance present in a smaller amount is called the solute.

→ A saturated solution is a solution in which no more solute can be dissolved at a particular temperature.

→ An unsaturated solution is a solution in which more solute can be dissolved at a particular temperature.

→ Water dissolves different amounts of substances in it and the solubility of most substances increases when the solution is heated.

→ Evaporation and condensation are opposite of each other.

→ Pure substance: If a substance is made up of only one type of component (atoms or molecules) it is called a pure substance. It must have definite composition and properties.

→ Impure substance: An impure substance is one that consists of a mixture of different types of molecules.

→ Mixture: A substance made up of two or more elements or compound mixed together in any ratio without any chemical reaction is called a mixture.

→ Solution: When a mixture of two or more substances appears like a single substance or pure substance it is called a solution.

→ Solvent: In a solution, the substance present in a larger amount is called the solvent.

→ Solute: In a solution, the substance present in smaller amounts is called the solute.

→ Saturated solution: A solution in which no more solute can be dissolved at a particular temperature is called a saturated solution.

→ Unsaturated solution: A solution in which more solute can be dissolved at a particular temperature is called a saturated solution.

→ Distillation: The process in which a liquid is converted into vapours by boiling it and the vapours so formed are condensed by cooling to give pure liquid is called distillation.

→ Hand-picking: The method of separating undesirable solid substances or impurities from useful solids by hand is known as handpicking.

→ Winnowing: When the particles of impurities are light or when light and heavy particles from a mixture then the winnowing method is used to separate them.

→ Threshing: The process of separating grains from the stalks is called threshing. In this method, we beat stalks to free the seeds.

→ Sieving: Sieving is a method in which smaller solid particles are separated from bigger and larger solid particles by passing through a sieve.

→ Sedimentation: In this process, the liquid mixture is placed undisturbed for some time. Solid heavy insoluble particles settle down and lighter particles float in the liquid.

→ Decantation: The process of transferring the liquid from the mixture without disturbing sediments is known as decantation.

→ Churning: The process of separation of lighter particles from a liquid mixture is churning.

→ Evaporation: Evaporation is a process in which liquid is converted into its vapours by heating.

→ Condensation: The process of converting water vapours into their liquid form is called condensation.

→ Filtrate: The clean liquid obtained during filtration is known as filtrate.

→ Residue: The sand and mud left on the filter paper is known as the residue.

This PSEB 6th Class Science Notes Chapter 4 Sorting Materials into Groups will help you in revision during exams.

PSEB 6th Class Science Notes Chapter 4 Sorting Materials into Groups

→ The matter is defined as anything that has mass and takes up space.

→ All material around us is matters because all materials occupy space and have mass.

→ Feelings of love or sadness, signals received by radio and television, different forms of energy do not matter.

→ Some of these substances are made up of one material whereas others are made up of more than one material.

→ Atom is the smallest part that is found in all types of matter.

→ We are surrounded by different substances having different shapes, sizes, colours, and uses.

→ Some articles can be made from different materials. There are certain different articles that are made up of the same materials.

→ Due to the large variety of objects, it is better if we classify these. We can classify these different bases i.e. shape, the material used, use, etc.

→ Objects made from one material have simple composition. Objects made from many materials have complex compositions.

→ Materials are used to make objects depending upon their properties and the purpose for which the objects are to be used.

→ Some materials have similar and some have dissimilar properties.

→ Some substances completely disappear when dissolved in water. These are called soluble substances.

→ Substances that do not mix with water or do not disappear in water even after stirring for a long time are called insoluble substances.

→ Some materials have a shining appearance. These are called lustrous.

→ The substances which have a dull appearance are called non-lustrous substances.

→ Some materials are hard. These are called rigid substances.

→ We can see across certain substances these are called transparent substances.

→ We cannot see across certain substances. These are called opaque substances.

→ We can see only up to a certain extent across some substances. These are called translucent substances.

→ Liquids that completely mix with each other are called miscible liquids.

→ Liquids that do not mix with each other are called immiscible liquids.

→ Liquids that partially mix with each other are called partially miscible liquids.

→ The mass per unit volume of a substance is known as density.

→ If an insoluble substance has a density higher than water then it will sink.

→ If an insoluble substance has a density lower than water then it will float.

→ Out of a pair of immiscible liquids, the one with the higher density will form the lower layer and the one with the lower density will form the upper layer.

→ Miscible: The liquids which mix completely are called miscible liquids.

→ Immiscible: The liquids which do not mix with each other are called miscible liquids.

→ Soluble: The solid substance that on dissolving in water or any other liquid completely disappear is called a soluble substance.

→ Insoluble: The solid substance that on dissolving in water or any other liquid that does not disappear is called an insoluble substance.

→ Transparent: The substances through which one can see, are called transparent.

→ Opaque: The substances through which one cannot see are called opaque.

→ Translucent: The substances through which one can see partially but not clearly, are called translucent.

→ Lustre: The shining that we see on a substance is called lustre.

→ Atom: The smallest part of the matter is known as an atom.

→ Texture: It means how we feel upon touching the surface of a substance.

→ Rigid: It means whether a substance can be compressed or not.

→ Density: The mass per unit volume of a substance is known as density.

This PSEB 6th Class Science Notes Chapter 3 Fibre to Fabric will help you in revision during exams.

PSEB 6th Class Science Notes Chapter 3 Fibre to Fabric

→ Clothes are important as they

• protect us from sunlight, wind, cold, heat, rain, etc.
• help us to feel comfortable in different weather conditions and to look smart.

→ People commonly wear different types of clothes like sari, coat-pent, suits, jeans,I shirts, T-shirts. Turban, kurta-pajama, salwar-kameez, lungi, dhoti, etc.

→ Cotton, silk, wool, and polyester are different variety of clothing materials, called fabrics.

→ Bedsheets, blankets, towels, curtains, duster, floor mats, our school bags, belts, socks, ties are made up of different kinds of fabric. Thus, different kinds of fabrics are used! to make different types of clothes.

→ Yarn is a thin thread used for making different fabrics. It is made from fibre.

→ Fibres are of two types:

• natural
• man-made (Synthetic).

→ Fibres that are obtained from nature are called natural fibre.

→ Natural fibres can be obtained from plants and animals.

→ Fibres obtained from plants are called plant fibres.

→ Similarly, fibres obtained from animals are called animal fibres.

→ Cotton, Jute, and coir are examples of plant fibres whereas wool, silk, etc. are examples of animal fibres.

→ Ginning, spinning, weaving, knitting, etc. are some processes that are used to make fabric or clothing material from cotton fibre.

→ The fibres made by man from, chemicals are called synthetic fibers.

→ Nylon, acrylic, and Polyester are examples of synthetic fibres.

→ Synthetic fibre is used to make socks, toothbrush bristles, car seat belts, carpets, ropes, school bags, etc.

→ Jute fibre is obtained from the stem of the jute plant by the process of retting.

→ Synthetic fibres dry easily, have lesser air spaces between them, are stronger and wrinkle-free.

→ Synthetic fibres do not absorb water, so these fibres are not suitable for hot and humid weather.

→ Cotton clothes are good for humid and hot weather. It absorbs water easily.

→ The process of separating cotton fibres from the seeds by combing is called ginning Removing of wool from sheep using clippers is called shearing.

→ The rearing of silkworms to produce silk.

→ The process of arranging two sets of yarn together to make a fabric is called weaving.

→ In contrast, a single yam is used to make a piece of fabric in knitting.

→ Knitting is done by hands or by machines.

→ Yarn: Yarn is a thin thread used for making different fabrics.

→ Fibres: Yarn is made up of very small strands called fibres.

→ Jute: Jute is strong and rough, the necktie is smooth and shiny as it is made up of silk.

→ Plant Fibres: The Fibres obtained from plants are called plant fibres.
For example cotton, jute, coir.

→ Animal fibres: The fibres obtained from animals are called animal fibres.
For example wool, silk.

→ Synthetic Fibres: Fibres prepared by a man using chemicals and other materials are called synthetic fibres.

→ Ginning: The separation of cotton from its seeds by steel combs is called ginning.

→ Sericulture: The rearing of silkworms to produce silk.

→ Retting: Formation of jute fibre from the stem of the jute plant by the process of retting.

→ Shearing: Removing wool from sheep using clippers.

→ Spinning: The process of making yarn from fibres is called spinning.

→ Weaving and Knitting: The process of arranging two sets of yarn together to make a fabric is called weaving.

→ In contrast, a single yarn is used to make a piece of fabric in knitting.

This PSEB 6th Class Science Notes Chapter 2 Components of Food will help you in revision during exams.

PSEB 6th Class Science Notes Chapter 2 Components of Food

→ Nutrients are the substances that are needed for the proper growth and development of the body.

→ Carbohydrates, proteins, fats, minerals, and vitamins are the main nutrients in our food.

→ In addition to these, our body needs water and roughage.

→ Carbohydrates are made up of carbon, hydrogen, and oxygen. These are instant sources of energy and are called energy-giving food.

→ Bajra, jowar, rice, wheat, jaggery, mango, banana, and potato are the main sources of carbohydrates.

→ We have two types of carbohydrates. These are simple carbohydrates and complex hydrates.

→ Examples of simple carbohydrates are glucose, fructose, sucrose, lactose, etc.

→ Examples of complex carbohydrates are starch, cellulose, glycogen, etc.

→ Carbohydrates sweet in taste are called sugars.

→ Sucrose is known as table sugar.

→ Fructose is called fruit sugar.

→ Lactose is called milk sugar.

→ Starch is tasteless and insoluble in water. It is made up of many glucose units.

→ The main sources of starch are potatoes, wheat, rice, maize, etc.

→ During digestion, starch is first converted into glucose and finally into carbon dioxide and water. So, starch is not an instant source of energy.

→ Starch detection can be done by an iodine test. It gives a blue-black colour with iodine.

→ Proteins are made up of carbon, hydrogen, oxygen, and nitrogen. They are called body-building foods.

→ The growth and repair of body cells is the main function of proteins. These also protect us from many diseases.

→ Plants and animals both are sources of proteins.

→ Proteins from plants are called plant proteins and proteins from animals are called animal proteins.

→ Beans like soybeans, peas, and pulses like gram and moon are sources of plant proteins.

→ We also get proteins from spinach, mushroom, broccoli, etc.

→ Mean, fish, poultry, milk, and milk products are the main sources of proteins.

→ Some proteins speed up various reactions occurring in our bodies. These are known as enzymes.

→ Enzymes are proteins that speed up various activities inside the body of a living organism.

→ Proteins when added to a solution of copper sulphate and caustic soda gives blue colour. This reaction is used for detecting the proteins.

→ Fats also give us energy. They give larger amounts of energy in comparison to carbohydrates. They do not release energy instantly.

→ Fats are known as the richest source of energy. Carbohydrates are known as instant sources of energy.

→ Important plant sources of fats are vegetable oils like mustard oil, coconut oil, and sunflower oil.

→ Other sources of fats are cashew, almonds, groundnut, and sesame seeds.

→ Important animal sources of fat are meat, eggs, fish, milk, and milk products like butter, ghee, etc.

→ Fats give energy, prevent heat loss from the body.

→ The presence of an oily patch on paper confirms the presence of fat in any food item.

→ Our bodies also need minerals. Calcium, iron, iodine, and phosphorus are important minerals. These do not give us energy.

→ Iron is needed for the formation of haemoglobin and calcium is needed for forming bones.

→ Phosphorus provides strength to bones and teeth.

→ Iodine is needed for the normal functioning of the thyroid gland.

→ Vitamins are essential for the proper functioning of our body.

→ We have different vitamins like A, B, C, D, E, and K.

→ Sources of vitamin A are eggs, meat, milk, cheese, green leafy vegetables, carrot, papaya, etc. It is needed for healthy eyes and skin.

→ Sources of vitamin B are milk, green vegetables, peas, eggs, cereals, mushrooms, etc. It is needed for normal growth and proper functioning of the central nervous system and digestive system.

→ Sources of vitamin C are citrus fruits (lemon, orange, etc.), amla, tomato, broccoli, etc. It is needed for fighting against diseases.

→ Sources of vitamin D are dairy products, fish liver oil, exposure to sunlight, etc. It is needed for healthy bones and teeth.

→ Sources of vitamin E are almonds, peanuts, sunflower oil, soyabean oil, leafy vegetables. It is needed for protecting cells from damage and helping our body to lower different problems.

→ Sources of vitamin K are green leafy vegetables, fish meat, eggs, cereals, etc. It is needed for the clotting of blood.

→ Nutrients: are the substances that are needed for the proper growth and development of the body.

→ Balance diet: The diet that contains an adequate amount of all the essential nutrients, roughage, and water for proper growth and development of the body is called a Balanced diet

→ Deficiency Diseases: The disease which is caused due to shortage of nutrients in our diet for a long time is called deficiency disease.

→ Goiter: A deficiency disease caused due to deficiency of iodine and its main symptom is an enlargement of the gland in the neck.

→ Scurvy: It is a disease caused by deficiency of vitamin C and its main symptoms include bleeding gums.

→ Beri-Beri: It is a disease caused by a deficiency of vitamin-B.

→ Rickets: It is a disease caused by deficiency of vitamin D and its main symptoms include softening and bending of bones.

→ Anaemia: It is a disease caused by deficiency of iron and its main symptoms include weakness, fatigue, and pale skin.

→ Roughage: The fibrous indigestible material present in food is termed roughage.

This PSEB 6th Class Science Notes Chapter 1 Food Where Does it Come From will help you in revision during exams.

PSEB 6th Class Science Notes Chapter 1 Food Where Does it Come From

→ All living beings need the energy to carry out their daily activities.

→ Food is needed by living beings for their growth, getting energy for doing work, replacement and repair of their damaged body parts, and protection against diseases.

→ Different varieties of food like fruits, vegetables, milk products, sweets, eggs, meat, chapati, and bakery products are present in nature.

→ The materials needed to prepare food items are called ingredients. Food materials can be made of one or two or many ingredients.

→ Plants are the chief source of food for us and other animals. However, few food materials are also obtained from animals.

→ Green plants can prepare their own food by using sunlight, carbon dioxide, and water to prepare their food. This process is called photosynthesis.

→ Every part of a plant where the food is stored is edible i.e. seed, flower, stem, root, leaf.

→ The plant parts which are used by us as food are called edible parts.

→ We eat roots of carrot, radish, turnip, sweet potato, etc. We also use stems of certain plants.

→ Some stems like those of ginger, potato, onion, turmeric grow underground and store food.

→ Stems of ginger and turmeric are used as spices.

→ The stem of sugarcane is used to make juice, sugar, and jaggery.

→ We eat different types of fruits like apple, mango, guava, papaya, orange, etc.

→ All these fruits are eaten raw i.e. without cooking. We make jams and pickles from some fruits.

→ Fruits are essential for good health as these are important sources of vitamins and minerals.

→ We use leaves of various plants like mustard, spinach, cabbage, coriander, mint, etc.

→ We use seeds of many plants as food like wheat, rice, maize, gram, peas, kidney beans and green gram (moong), etc.

→ Seeds of some crops like gram, peas, kidney beans, and green gram (moong) are known as pulses whereas seeds of wheat, rice, and maize are known as cereals.

→ We get milk, honey, meat, eggs, oil, etc. from animals.

→ Honey contains sugar, water, minerals, enzymes, and vitamins. Nectar of flowers is a source of honey.

→ On the basis of the food taken by animals, there are three categories of the animals:

• Herbivores
• Carnivores
• Omnivores

→ Herbivores are the animals that eat only plants and plant products are called herbivores, e.g. cows, goats, rabbits, sheep, deer, elephants, etc.

→ Carnivores are the animals which eat other animals are called carnivores, e.g. lions, tigers, lizards, snakes, etc.

→ Omnivores are the animals which eat both plants and animals are called omnivores. e.g. Crow, bear, dog, and rat, man, etc.

→ Milk contains proteins, sugar, fats, and vitamins.

→ It is used worldwide as food that can be converted into dairy products like cheese, butter, curd, cream, etc.

→ People eat the meat of goats, sheep, chicken, fish, and sea animals like prawns, crab.

→ Meat is also used as food and it contains a great number of proteins and fats.

→ People eat eggs of hen and duck and other birds.

→ The white part of the egg is called albumen and the yellow part of the egg is called yolk.

→ Albumen is rich in proteins and you are rich in fats.

→ Food: Substances providing energy to do work, maintain body heat, protect us from diseases, etc. is called food.

→ Balance diet: A diet that contains all the nutrients needed by the body is called a balanced diet.

→ Edible: The substances/materials which are safe for eating are called edible substances.

→ Ingredients: Materials needed to prepare food Items.

→ Pulses: Seeds of some crops like gram, peas, moong.

→ Cereals: Seeds of grass crops e.g. wheat, rice, maize

→ Albumin: White part of the egg.

→ Yolk: Yellow part of the egg

→ Nectar: Sugary fluid present in flowers

→ Herbivores: Plant-eating animals are called herbivores.

→ Nectar: Sugary fluid present in flowers

→ Autotrophs: Organisms that can prepare their own food by photosynthesis.

→ Heterotrophs: Organisms that depend on other organisms for food

→ Herbivores: Organisms that eat only plants and plant products

→ Carnivores: Animals eating other animals are called carnivores.

→ Omnivores: Animals that eat both plants and animals are called omnivores.

Punjab State Board Syllabus PSEB 9th Class Welcome Life Notes Pdf in English Medium and Punjabi Medium are part of PSEB Solutions for Class 9.

PSEB 9th Class Welcome Life Notes in English Medium

• Chapter 1 Self Awareness and Self Discipline Notes
• Chapter 2 Critical Thinking Notes
• Chapter 3 Interpersonal Relationships Notes
• Chapter 4 Empathy Notes
• Chapter 5 Creative Thinking Notes
• Chapter 6 Managing Emotions Notes
• Chapter 7 Decision Making Notes
• Chapter 8 Problem Solving Effective Notes
• Chapter 9 Effective Communication Notes
• Chapter 10 Coping with Stress Notes

Punjab State Board Syllabus PSEB 7th Class Social Science Notes Pdf in English Medium and Punjabi Medium are part of PSEB Solutions for Class 7.

PSEB 7th Class Social Science Notes in English Medium

PSEB 7th Class Social Science Notes Geography: Our Environment

• Chapter 1 Environment Notes
• Chapter 2 The Internal and External Face of the Earth Notes
• Chapter 3 Atmosphere and Temperature Notes
• Chapter 4 Ocean Notes
• Chapter 5 Natural Vegetation and Wildlife Notes
• Chapter 6 Human Environment – Settlements, Means of Transport and Communication Notes

PSEB 7th Class Social Science Notes History: Our Past-II

• Chapter 7 The Medieval India Notes
• Chapter 8 New Kings and Kingdoms (A.D. 700-1200) Notes
• Chapter 9 Political Developments in South India (A.D.700-1200) Notes
• Chapter 10 The Delhi Sultanate Notes
• Chapter 11 The Creation of an Empire – The Mughal Empire Notes
• Chapter 12 Monumental Architecture Notes
• Chapter 13 Towns, Traders and Craftsmen Notes
• Chapter 14 Tribes, Nomad and Settled Societies Notes
• Chapter 15 Religious Developments Notes
• Chapter 16 The Development of Regional Cultures Notes
• Chapter 17 India in the Eighteenth Century Notes

Social Science Notes for Class 7 PSEB Civics: Democracy and Equality

• Chapter 18 Democracy and Equality Notes
• Chapter 19 Democracy – Representative Institutions Notes
• Chapter 20 State-Government Notes
• Chapter 21 Media and Democracy Notes

This PSEB 7th Class Science Notes Chapter 18 Wastewater Story will help you in revision during exams.

PSEB 7th Class Science Notes Chapter 18 Wastewater Story

→ Sewage is liquid waste, most of it is water that has dissolved and suspended impurities. These impurities are called contaminants.

→ An underground network of pipes that carry wastewater from a home to a point of disposal is called Sewerage.

→ Sewage is transported through the closed pipes to the wastewater treatment plants where pollutants are separated and reformed and then flow into rivers and oceans.

→ During wastewater treatment pollutants are separated by physical, chemical, and biological methods.

→ Sludge is a solid that settles to the bottom during water purification.

→ Wastewater treatment co-products are sludge and biogas.

→ A manhole is a lid-covered open space through which a person can enter and can check the sewerage system.

→ Open defecation is a breeding ground for flies, mosquitoes, and other insects that cause many diseases.

→ Do not throw oil, ghee, grease, etc. in a drain or in the open. Doing so will make drain chock.

→ Throw trash only in the bin (dustbin).

→ Pollutants: Dissolved and suspended impurities in dirty water are called pollutants.

→ Sewerage: A network of small and large pipes that carry wastewater to the drainage area.

→ Manhole: Large open mouth holes are made at every 50-60 meters of the sewerage system.

→ Individual who enters the sewage can check and remove sewage problem if any.

→ Water Treatment Plant: A place where impurities are separated from wastewater.

→ Water Treatment: The process of separating impurities from wastewater is called water treatment.

→ Sludge is the solid that settles in the sewage water purification tank.

→ Septic tank: This is a small system of sewage treatment containing monoaerobic bacteria that remove waste products. It has connections with main sewage pipes.