PSEB Notes

This PSEB 6th Class Social Science Notes Chapter 1 Earth – As a Member of Solar System will help you in revision during exams.

PSEB 6th Class Social Science Notes Chapter 1 Earth – As a Member of Solar System

→ Universe: The Universe is a vast and infinite space having millions of galaxies and heavenly bodies.

→ Galaxy Or Milky Way: A Galaxy is a group of millions of shining stars scattered in space. It is also known as Milky Way or Akash Ganga.

→ Star: A star is a celestial body having its own heat and light.

→ Planet: A planet is a heavenly body that revolves around the sun and receives heat and light from it.

→ Satellite: A satellite is a small spherical body that revolves around a particular planet.

→ Light Year: A light-year is a distance, which a ray of light would cover in a year’s time.

→ Solar System: The sun, planets, and other heavenly bodies combine together to form the solar system.

→ Sun-spots: The black spots on the bright face of the sun are called sun-spots.

→ Orbit: Orbit is the fixed path along which the planets revolve around the sun.

→ Comets: Comets are heavenly bodies with a head and a tail.

→ Saptarishi: A constellation of seven stars and a part of the Big Bear.

→ Asteroids: Tiny bodies found between the orbit of Mars and Jupiter.

→ Neil Armstrong: The first man to set foot on the moon.

→ Moon: Natural Satellite of the earth.

→ Celestial Bodies or Heavenly Bodies: All the objects like the sun, moon and bright objects seen during the night in the sky are called celestial bodies.

→ Constellation: A group of stars forming a particular pattern or design is called a constellation.

→ Geoid: Geoid means Earth-like shape.

→ Man-made satellites: Satellites carried by rockets and placed in the orbit of the earth

→ Meteoroids: Small pieces of rocks which revolve around the sun.

→ Full Moon: The night of Poornima when the moon shines in the form of a ball.

→ New Moon: The night of Amavasya when the moon is not seen from the earth.

→ On 23rd August, the International Astronomical Conference decided that Pluto should not be considered as a planet as it does not fulfill the essentials of a planet.

→ The distance between the earth and the sun is 150 million kms.

→ Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune are the 8 planets.

→ The earth has a circumference of 40,000 km.

→ The earth has an equatorial diameter of 12,756 km.

→ The distance between earth and moon is 3,76,275 km.

→ The sun is the nearest star to us.

→ The earth is the only planet having water and life.

→ The earth is a unique planet in the Solar System.

→ A light-year is a unit to measure the distance between the bodies of the universe.

→ Neil Armstrong and Edwin Aldrin were the first cosmonauts to land on the moon on 21st July 1969.

→ The universe is huge and it includes the sun, satellites, planets, stars, etc.

→ The power of attraction of the sun, planets are called gravity.

→ Diameter = 12,756 km & 12,712 km.

→ Circumference = 40,000 km.

→ Space: Space means sky.

→ Kalpana Chawla: Astronaut of Indian Origin.

→ Saptrishi: A constellation in Great Bear.

→ Speed of light: 3 Lakh km per second.

→ Milky way: Akash Ganga in India.

→ Apollo Project: To know more about Moon.

→ Tailed Star: A comet.

→ Gravity: Power of attraction of the Sun.

This PSEB 6th Class Science Notes Chapter 16 Garbage Management and Disposal will help you in revision during exams.

PSEB 6th Class Science Notes Chapter 16 Garbage Management and Disposal

→ Any substance which is no more useful is called waste.

→ Solid waste is called garbage. It is generated by human activities.

→ Garbage has both useful and non-useful components.

→ There are many types of wastes like industrial waste, domestic waste, agricultural waste, biomedical waste, etc.

→ Two types of garbage or solid waste are biodegradable wastes and non-biodegradable waste.

→ For proper disposal of garbage, we must do segregation before disposing of the garbage. We can do this by using differently colored dustbins.

→ To manage the waste there is the 4R’s i.e. reuse, reduce, recycle, refuse.

→ Some parts of the garbage can be reused.

→ Usually, garbage is collected and thrown in landfills.

→ Composting or vermicomposting can be done of useful components or biodegradable components of garbage.

→ Dry leaves, husk of wheat, and part of crops should not be burnt as they produce lots of smoke and harmful gases.

→ Red worms are good for vermicomposting of vegetable and fruit waste, coffee and tea leaves, weeds, etc. but oily, pickled, salty food, and milk products are not good for red worms.

→ Some types of plastics, paper, glass, and metal can be recycled.

→ Plastics bum with a foul smell and produce lots of harmful gases.

→ Plastic bags cause choking of drains and sewer systems.

→ Plastic bags eaten by animals are the cause of their death.

→ Plastic is useful as things made of them last long.

→ The incineration method releases harmful gases and causes pollution.

→ e-waste includes discarded mobiles or any electronic device.

→ Garbage: The solid waste is called garbage.

→ Dump: A large low-lying area used to dispose of garbage.

→ Landfill: A low-lying area to be filled by garbage is a landfill.

→ Biodegradable Waste: Waste material that can be decomposed by the action of microorganisms into harmless substances.

→ Non-biodegradable Waste: The waste materials that cannot be decomposed easily.

→ Incineration: The process of burning waste in closed containers.

→ Compost: The decomposition of organic material into useful material is compost.

→ Vermi-Composting: The method of preparing compost with the help of red worms is vermicomposting.

→ Gizzard: The teeth like hard structures present in red worms for grinding purposes is called the gizzard.

→ Recycling: The process of using a few materials, again and again, is recycling.

This PSEB 6th Class Science Notes Chapter 15 Air Around Us will help you in revision during exams.

PSEB 6th Class Science Notes Chapter 15 Air Around Us

→ All living things require air to live.

→ Air is present everywhere around us however we cannot see the air.

→ Our earth is surrounded by a thin layer of air that extends upto many kilometres above the surface of the earth. This is known as the atmosphere.

→ Air is made up of water vapours, Oxygen, Nitrogen, Carbon dioxide, dust, and smoke.

→ Nitrogen and Oxygen are the main constituents of air and are present in large quantities.

→ In the air, nitrogen is 78% and oxygen is only 21%.

→ Oxygen is required for burning.

→ Carbon dioxide is a greenhouse gas.

→ The balance of Oxygen and Carbon dioxide in the atmosphere is maintained by the presence of living organisms (man, animals) and plants.

→ Carbon dioxide is used by plants for producing food by photosynthesis. They release oxygen.

→ Oxygen is consumed by animals and humans for respiration. They produce carbon dioxide.

→ Carbon dioxide is used as a fire extinguisher because carbon dioxide does not support g burning.

→ Air can be compressed and it also exerts pressure.

→ Moving air is called wind.

→ Moving air has the power to rotate a windmill which produces electricity.

→ Windmills are very useful as they produce electricity.

→ Air helps in the dispersal of seeds, pollens, and movement of sailing boats, yachts, gliders, aeroplanes, etc.

→ Dispersal of pollens is known as pollination.

→ Ozone present in the upper layer of the atmosphere protects us from the UV rays of the sun.

→ Air: It is a mixture of many gases like nitrogen, oxygen, carbon dioxide, water vapours, etc.

→ Wind: The moving air is wind.

→ Windmill: A device that is being rotated by air and is used for producing electricity.

→ Atmosphere: The thin blanket of air surrounding the earth constitutes the atmosphere.

This PSEB 6th Class Science Notes Chapter 14 Water will help you in revision during exams.

PSEB 6th Class Science Notes Chapter 14 Water

→ Water is a vital resource and is considered a boon to live.

→ Water is present all over the earth.

→ Around the 3/4th part of the earth, the surface is covered with water.

→ The human body consists of 70% of water.

→ We need water for our daily activities and for producing other things.

→ Two main sources of water are surface water and groundwater.

→ Water exists in three states i.e. solid, liquid, and gas.

→ We get water from ponds, lakes, rivers, wells, etc.

→ Sea or Ocean water is salty. It is not fit for drinking and for domestic, agricultural, and industrial needs.

→ As water is a vital resource so it must be conserved.

→ Judicious use of water and saving it is conservation of water.

→ Rainwater is a pure form of water and is safe for drinking.

→ Rainwater harvesting is a technique that conserves water by storage of rainwater. This water can be reused for different useful purposes.

→ The water cycle is a cyclic process in which water is circulated between the earth and the atmosphere.

→ Ocean water supplies water to the water cycle and thus plays an important role.

→ Water from oceans, lakes, wet clothes and plants gets evaporated.

→ Clouds are just the condensation of evaporated water in the air.

→ Clouds cause rains and water returns to earth, oceans, lakes, etc.

→ Snow on mountains melts and water runs into rivers.

→ Water is also absorbed by the ground and becomes available to us as groundwater.

→ Heavy rains and no rains cause too many problems.

→ Heavy rains cause floods which destroy lives and properties.

→ Overflow of water in a large amount beyond its normal limits is known as a flood.

→ A flood is a natural disaster.

→ No rain or very little rain in a region is caused by the drought.

→ In drought conditions availability of food, fodder, and water become negligible.

→ With the increase of population, industries, and agriculture also increase which lay stress on the use of water.

→ Melting: The process of conversion of solid into liquid is called melting.

→ Freezing: The process of converting liquid into solid is called freezing.

→ Evaporation: The process of converting liquid into its vapours is called evaporation.

→ Transpiration: The process by which plants lose their water in the air is called transpiration.

→ Condensation: The process of conversion of water vapours into water is called condensation.

→ Precipitation: Falling of water in the form of rain and snow is called precipitation.

→ Clouds: The condensed water droplets join together to form clouds.

→ Water cycle: The evaporation of water to air, formation of clouds by condensation, and falling of rain on the earth constitutes the water cycle in nature.

→ Rainwater harvesting: Collection of rainwater for use at a time when it is not available otherwise is rainwater harvesting.

This PSEB 6th Class Science Notes Chapter 13 Fun with Magnets will help you in revision during exams.

PSEB 6th Class Science Notes Chapter 13 Fun with Magnets

→ Magnetite is a natural magnet.

→ Some rocks have the property of attracting pieces of iron and these are called natural magnets.

→ Magnet has the property of attracting iron, cobalt, and nickel. Such substances are called magnetic substances.

→ Every magnet has two poles:

• North Pole
• South pole

→ A freely suspended magnet sets itself in a North-South direction.

→ Unlike (opposite) poles of two magnets attract each other whereas like poles repel each other.

→ Man-made magnets are called artificial magnets.

→ Magnets made from iron pieces are called artificial magnets.

→ Magnets are of different shapes such as Bar magnet, Horseshoe shaped (U-shaped) magnet, cylinderical magnet, or spherical magnet.

→ Compass is used to find direction.

→ When a magnet is brought near a compass, its needle gets deflected.

→ On heating a magnet, striking it with a hammer, or dropping it from a height it loses its property of magnetism.

→ If a magnet is not properly stored then it loses its property with time.

→ To store bar magnets with safety the opposite poles of two magnets are placed facing each other.

→ The magnet should be kept away from cassettes mobiles, TVs, CDs, and computers, etc.

→ Compass: Compass is a device that is needed to determine direction.

→ Magnet: Such substances which have the property of attracting iron are called magnets.

→ Magnetite: Magnetite is a natural magnet that was first discovered by a Shepherd named Magnus.

→ North pole: That end of a freely suspended magnet that points towards the geographical north direction is called its North pole.

→ South pole: That end of a freely suspended magnet that points towards the geographical south direction is called its South pole.

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.