Grade 7 · Science · Unit 7 of 14
Growing Crops Well
Soil, nutrients and care for the land
What your child practises
Fertilizers and soil nutrients, selective breeding, crop rotation, chemical and biological pest control and farming practices that protect soil and water.
Alberta Curriculum learning outcome: Unit B: Plants for Food and Fibre · soil nutrients, plant breeding, pest control and sustainable growing methods
Sample questions
A taste of this unit. In the app, questions change every time and get easier or harder to match your child.
Question 1
Why do farmers test their soil?
- To make the soil heavier
- To count the worms for a prize
- To change its colour
- To find out which nutrients are low so they add only what is needed
Show answer
To find out which nutrients are low so they add only what is needed
Hint: Soil tests help farmers use fertilizer wisely.
Question 2
Too much fertilizer runs off a field into a stream. What can happen?
- The soil gets better in the stream
- Fish grow faster everywhere
- The stream becomes cleaner
- Algae grow too much and can harm other life in the water
Show answer
Algae grow too much and can harm other life in the water
Hint: Extra nutrients are not only taken up by crops.
Question 3
Earthworms in soil help plants by…
- making the soil dry
- eating all the roots
- blocking out the light
- loosening the soil and mixing in organic matter
Show answer
loosening the soil and mixing in organic matter
Hint: Their tunnels let air and water reach roots.
Question 4
A bag of potatoes sprouts in a cupboard. A gardener cuts the pieces with eyes and plants them. This is…
- photosynthesis
- growing new plants from a part of a plant instead of from seeds
- using fertilizer
- pollination
Show answer
growing new plants from a part of a plant instead of from seeds
Hint: Plants can be grown from stems, tubers and cuttings as well as seeds.
Question 5
Which is a possible problem with spraying chemicals on crops?
- They remove all weeds forever
- They can harm helpful insects and spread to water
- They always increase rainfall
- They make the crop have no roots
Show answer
They can harm helpful insects and spread to water
Hint: Chemicals don't always stay where they were sprayed.
Question 6
In the 1930s, drought and wind blew away topsoil on parts of the Prairies. How do farmers now help prevent this?
- Remove every plant after harvest
- Leave crop stubble in the field and avoid turning over the soil as much
- Grow only on bare soil
- Never plant anything
Show answer
Leave crop stubble in the field and avoid turning over the soil as much
Hint: Covered soil is held in place.