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 type. Ideal 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
Comparative & Superlative with -er/-est
We use -er / -est with the following adjectives:
Two-syllable adjectives with the following endings:
A quick look at the grade 2 lesson on introduction to multiplication
Taming the tables – Tips to introduce multiplication
While multiplying always remember :
An even number x an even number = an even number
An odd number x an even number = an even number
An odd number x an odd number = an odd number
Distributive property of multiplication
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 Continue reading
A look at the grade 2 lessons
Grade 2 Science (NSO): Human Body
Human beings: Parts of the body
Human beings : Sense organs
Our body is made up of different organs and organ systems. There are in all 12 systems in our body
Food Decay and Preservation
Bacteria and fungi are the main groups of decomposer organisms. Food decay is also known as food spoilage.
Bacteria and fungi need Food , Warmth and Moisture to grow.
There are several ways to stop or slow down the decay of foods. This is known as Food Preservation.
Food preservation methods
Bacteria cannot reproduce at low temperatures.
Bacteria and fungi need warmth to grow. In low temperatures they stop growing.
Following is the list of food preserved by freezing;
- Fresh foods
- Cooked foods
Removing water prevents the microorganisms from growing, or digesting the food.
A look at the grade 2 lesson
Grade 2 Science(NSO) : Food
Food can be divided into three types
Energy giving food
Give us energy to work. They contain carbohydrate and fats.
They are found in foods like rice, pasta, cassava, yam etc. when starchy foods are eaten and digested, simple sugars like glucose are obtained. It is this glucose that the body uses for energy.
There are two major types of carbohydrates:
1. Simple carbohydrates (Sugar)
- White sugar you would find in a sugar bowl
Cooking of food
Cooking improves the flavor of food and also makes the food easier to chew and more digestible. Micro oirganisms present in the food are killed during cooking which makes the food safer to consume. Various methods of cooking are listed below :
Involves cooking the food at the boiling temperature of water ie 100 degree centigrade.
Example : Eggs , potatoes etc
Before starting lets take a look at the Grade 1 lessons
Air and Water : Properties
Air and Water : Use
Activities: Worksheets on Air and Water
Living things need air to breathe
Moving air is called Wind
A gentle wind is called Breeze
A strong fast wind is called a Storm
A very strong wind is called Gale
Uses of moving air
A weather cock or wind vane is used to know the direction of the wind. At airports we use wind sock to know the direction of the wind. When aeroplanes fly in the direction of the wind , it saves fuel.
Wind makes windmill work. They are used to generate wind energy which is used to grind grains, pump water and make electricity.
Helps in sailing boats
A parachute falls slowly because of the wind