Humans need food to _____.
survive
Plants make their own food through the process of _____.
photosynthesis
Plants use the _____ stored in food for growth.
energy
Fertilisers are substances added to soil to increase the amount of _____ for plant growth.
nutrients
Chemical substances sprayed onto plants or crops to destroy pests are called _____.
pesticides
Food provides humans with nutrients to grow and the _____ to carry out daily activities.
energy
In plants, _____ traps sunlight to make sugar as food.
chlorophyll
Oxygen is needed to release the energy stored in food through the process of _____.
respiration
A rapid growth of algae in a water body is known as an _____ bloom.
algae
Chemical substances that destroy weeds but do not harm the crops are known as _____.
herbicides
The food we eat comes from _____ and animals.
plants
Chlorophyll in plants traps _____ to make sugar as food.
sunlight
During photosynthesis, carbon dioxide and water are taken in by plants grown in _____ and in water.
soil
During an algae bloom, plants at the bottom of the pond die because they are unable to carry out _____.
photosynthesis
Pesticides and herbicides can be carried by _____ into rivers, lakes and ponds.
rainwater
As the world _____ increases, we need to produce more food.
population
Two raw materials for photosynthesis are _____.
carbon dioxide; water
Apart from sunlight, air and water, _____ are important for plants to grow well.
nutrients
Animals such as insects and rats that feed on crops and destroy them are called _____.
pests
The control of pests by their predators is known as _____ control.
biological
There is limited _____ for growing crops and raising livestock.
land
Two products of photosynthesis are _____.
sugar; oxygen
Apart from sunlight, air and water, an appropriate _____ is important for plants to grow well.
pH
_____ are plants that grow among crops and compete with them for nutrients.
Weeds
In the _____ method, trees are cut down and burned to clear forest land for growing crops.
slash-and-burn