Unit 7 Living Things and Air
Common gases
Composition of the air
What is air?
Uses of the gases in air
Breathed and unbreathed air
What makes these differences?
Respiration
How air passes in and out of us
Breathing in and out
Different breathing systems
Do plants respire?
How do plants obtain energy?
Most plants contain starch
Photosy nthesis
Oxygen carbon dioxide balance
Photosynthesis and food chains
Food webs
The pollution of our air
Summary
Difficult words
Unit 8 Electricity
Use of electicity
Conductors insulators
Electric current
Resistance
Lighting and heating effects
Fuses and circuit breakers
Electricity at home
Magnetism
Electromagnets
Electrochemistry
Summary
Difficult words
Unit 9 Heat Transfer
Unit 10 Hydrogen,Acids and Alkalia
Unit 11 Detecting the environment
Unit 12 Forces and Movement
Index
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