Class 3 NSO : Soil types

What is soil

Soil is formed by erosion that is breaking up of rocks , by the action of sun, wind and rain. It forms at the surface of land and  is the “skin of the earth.” Soil is capable of supporting plant life and is vital to life on earth.

Soil contains a lot of different things;  a few essential ingredients are listed below:

Sediment Every soil contains some mixture of sediments.  The three main sediments are sand, silt, and clay. The type of sediments  determines a soil’s typeIdeal soils (for farming) are a mixture of the three. 

Organic Matter – Soil contains a lot of partially decomposed organisms which is called organic matter. Microbes in the soil break it down to make important nutrients. Most organic matter comes from plants. This is also called Humus and is dark brown or black in color.

Minerals – There are tons of different minerals in the soil. They’re used by plants for growth. When plants die, their minerals return to the Earth.

Types of soil and properties

 

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Class 3 NSO : papers

Grade 3 NSO papers

 

nso-ieo-imo-nco

nso-ieo-nco-imo

nso-ieo-imo-nco

nso-imo-ieo-nco

NSO_1

Grade3NSO_2

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Grade 3 Science (NSO) : Earth and Universe

A look at the previous lessons on earth and universe :

Grade 2 Science (NSO) : Earth and universe

Weather and The Sky: Earth and Sky fundamentals

Earth’s Revolution

The motion around the sun along its orbit is called a revolution . The amount of time it takes for a single trip around the sun is called a period of revolution. The period for the Earth to revolve around the sun is 365.24 days or one year. The .24 days is why every four years February has 29 days.

There are 4 seasons in an year .In Autumn and Spring the northern and southern hemispheres are tilted equally toward the sun.In Summer the Earth is on the other side of the sun and the northern hemisphere is tilted  toward the sun and gets better sun rays. In winter the northern hemisphere is tilted away from the sun. That’s how we get seasons.

Earth’s orbit around the sun is slightly elliptical, Earth is actually slightly closer to the sun in the winter than it is in the summer.It is the tilt of Earth’s axis that causes the seasons.

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Grade 3 science (NSO) : Human body part 3

Links to part 1 and part 2 of the human body

Grade 3 Science (NSO) : Human body part 1

Grade 3 Science(NSO) : Human body part 2

Nervous system

This system controls all our actions, sense of feelings and thinking is called Nervous system.The nervous system is a complex collection of nerves and specialized cells known as neurons that transmit signals between different parts of the body. It is essentially the body’s electrical wiring.

  • It consists of the brain, spinal cord, sensory organs, and all of the nerves that connect these organs with the rest of the body
  • Brain is the most vital organ of our body
  • It sends and receives messages to and from all parts of the body through nerves
  • Spinal chord is the bundle of nerves that runs up and down the center of the back; connects the brain to the nerves; carries signals between the brain and other parts of the body
  • The brain and spinal cord form the control center known as the central nervous system (CNS).

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Grade 3 Science(NSO) : Human body part 2

We have already covered Skeletal, immune, cardiovascular, muscular and integumentary system in part 1.

Grade 3 Science (NSO) : Human body part 1

Lymphatic system :

It is responsible for the removal of interstitial fluid from tissues. It absorbs and transports fatty acids and fats as chyle from the digestive system. It transports white blood cells to and from the lymph nodes into the bones.

-picks up fluids leaked from the capillaries
-supports immune systems: houses white blood cells
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Grade 2 Science (NSO) : Earth and universe

A quick look at the Grade 1 lessons :

Weather and The Sky:GK questions on space

Weather and The Sky: Earth and Sky fundamentals

 Solar system

Sun :

  • It is a star.
  • It gives us heat and light
  • It is the main source of energy on the earth
  • Eight planets and many heavenly bodies revolve around the sun.

Planets :

  • Orbits the sun
  • Has sufficient mass to be round, or nearly round
  • Is not a satellite (moon) of another object

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Grade 3 Science (NSO) : Birds

Bird, a warm-blooded vertebrate that lays eggs and has feathers and wings.

Type of beaks

 

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Grade 3 Science (NSO) : Animals

A look at the grade 2 lessons :

Animals:Lifecycle

Animals:Animal homes

Grade 2 science (NSO) : Animals

Animals:Baby names

Animals:Domestic and Wild

Animals: Classification

Animals:Facts about animals

Animals and the way they eat

Herbivores : Animals like cows , buffaloes , sheep etc., that eat plants.
Carnivores : Animals like lions, tigers, etc., that prey on and eat other animals.
Omnivores : Animals like bears, crows etc., that eat both plants and animals.
Scavengers : Animals like vultures and jackals that eat dead and left over animals generally preyed on by carnivores.

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Grade 3 Science(NSO):Plants : Stem

Stem

Stems are the aboveground structures that bear the plant’s leaves and flowers. The stem provides a host of services to the plant:

  • It provides a pathway for transporting water up to the leaves, and moving the sugars produced in the leaves down to nourish the roots.
  • It acts as a sturdy mast to hold up the leaves and help orient them for maximum exposure to sunlight.
  • It can act as a storage site for carbohydrates.

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Grade3 Science (NSO) : Plants :Roots

Plants :Roots

Root

Root is the underground part of the plants body. It fixes the plant within the soil and absorbs water and mineral nutrients from the soil. It also stores excess food.

Function of roots

  • Roots attach the plant body to the ground. It provides support to the plant and helps in holding the plant firmly in the ground.
  • Root hairs of the plant absorb water and mineral from the soil and pass it to the stem.
  • Some roots like carrot, radish etc. store food.
  • Root bind the soil which otherwise may be blown away by wind or washed away by water. Root prevents soil erosion.

Types of roots

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