Biology class 7

What does soil contain?

• Water and air

• Water and plants

• Rocks, minerals, organic matter, air and water

• Water, air, plants

A mixture of weathered rock organic matter is called?

• Rocks

• Humans

• Bed rock

• Soli

What are the biological agents helps in soli formation

• Wind

• Water

• Climate

• Round worms

Skin diseases can be reduced by -----therapy?

• Water

• Breath

• Soil

• All the above

Weathering of rock is a -----+process

• Fast

• Very slow

• Very fast

• None

Red soil contains

• Oxides of calcium

• Oxides of iron

• Oxides of nitrogen

• Oxides of phosphorus

The soil layer which have leafy litter and humas

• A horizon

• O horizon

• E horizon

• C horizon

Organisms that are present

• Bacteria

• Fungi

• Earthworm

• All the above

Which colour of soil is richer in organic matter?

• Dark colour

• Light colour

• Red colour

• Yellow colour

Pulses are grown well in

• Sandy

• Loamy

• Sandy- Loamy

• Clay