Increasing Crop Yields

Question 0

What is the outcome of keeping plants enclosed in a glasshouse? (What does it keen away?)

Answer 0

Keeps plants free of pests and diseases.

Question 1

You can artificially create the ideal conditions for photosynthesis in what two kinds of buildings?

Answer 1

• Glasshouses

* polytunnels

Question 2

What do commercial farmers do to increase photosynthesis after the sun has gone down?

Answer 2

Supply artificial light

Question 3

Glasshouses trap the sun’s hear to keep the plants warm. What can farmers do in the winter to keep the ideal temperature?

Answer 3

Use a heater.

Question 4

What can farmers do to increase the amount of carbon dioxide in glasshouses?

Answer 4

Use a paraffin heater. As the paraffin burns, it makes carbon dioxide as a by-product.

Question 5

What is the effect of increasing the temperature, carbon dioxide concentration and light?

Answer 5

• Faster rate if photosynthesis
• plants will grow faster and bigger
• crop yields will be higher

Question 6

What are fertilisers used for?

Answer 6

To ensure the crops have enough nutrients.

Question 7

What are the 3 elements that plants need in order to make important compounds like proteins?

Answer 7

• nitrogen
• potassium
• phosphorus

Question 8

What is the effect of plants not getting all the elements they need?

Answer 8

Their growth and life processes are affected.

Question 9

What so farmers use fertilisers for?

Answer 9

To replace missing elements or provide more of them. This helps to increase the drop yield.

Question 10

What does pest stop?

Answer 10

Pests eating crops

Question 11

Pests include: Microorganisms, insects and mammals. Pests that feed on crops are killed using various methods of lest control. What does this result in?

Answer 11

Fewer plants are damaged and destroyed, increasing crop yield.

Question 12

Pesticides are a form of chemical pest control. Are pesticides dangerous to humans and other wildlife?

Answer 12

• often poisonous to humans.
• used carefully to keep amount of presto use in food below a safe level
• harm other wildlife.

Question 13

What is the alternative to using past control?

Answer 13

Biological control.

Question 14

What is biological control?

Answer 14

Using other organisms to reduce the numbers of pests: by encouraging wild organisms or adding new ones.

Question 15

Helpful organisms used in biological control could be which three?

Answer 15

• predators
• parasites
• disease-causing

Question 16

Biological control can have a longer-lasting effect than spraying pesticides and can be less harmful to wildlife. But introducing new organisms can cause problems like what? (Give an example!)

Answer 16

Can roads were introduced to Australia to eat beetles, but they are now a major pest themselves because they poison the native species that eat them.