Topic 1: Unit-1

Question 1

What is a system?

Answer 1

A system is something that is made up of many different parts that work together.

Question 2

The 4 spheres that interact to sustain life?

Answer 2

1. The Lithosphere
2. The Hydrosphere
3. The Atmosphere
4. The Biosphere

Question 3

What is the Lithosphere?

Answer 3

Solid, rocky layer covering the earth

Question 4

4 Reasons as to why soil is essential for living organisms?

Answer 4

1. To anchor plants
2. Habitats for animals
3. Source of nutrients for crops
4. Rich source of minerals e.g coal; iron; gold

Question 4

What does the Lithosphere include?

Answer 4

Rocks, soil and minerals

Question 5

What is the Hydrosphere?

Answer 5

Combined masses of water in all its forms on earth including liquid, gas or solid

Question 6

What does the Hydrosphere include?

Answer 6

Water in oceans, rivers, lakes, water vapour, ice

Question 7

Division of water on Earth?

Answer 7

97% = salt water > 3% = fresh water - 2% of which is frozen

Question 8

Use of water on earth?

Answer 8

helps to maintain constant temperatures on the earth

Question 9

What is the Atmosphere?

Answer 9

Layers of various gases surrounding our planet

Question 10

Division of air on Earth?

Answer 10

79% nitrogen; 21% oxygen; +- 4% CO2 & others

Question 11

4 reasons why the atmosphere is vital for living organisms?

Answer 11

1. Provides oxygen for respiration
2. Maintains constant temperatures
3. Traps heat from the sun to sustain life
4. Ozone layer prevents damage from UV rays

Question 12

What is the Biosphere?

Answer 12

Composed of all living organisms

Question 13

What does the Biosphere include?

Answer 13

plants, animals, microorganisms and their interactions with the other spheres