Climate zones

Question 1

What are base temperatures?

Answer 1

Below the base temperature plants can’t grow so it determines the earliest sowing date (wheat=0 degrees and maize=10 degrees)

Question 2

What effects crop growth?

Answer 2

• Temperature (optimum and maximum)
• Precipitation (quantity and timing)
• Day length
• Life cycle length

Question 3

What is the equation for photosynthesis?

Answer 3

6CO2 + 6H20 = C6H12O6 + 6O2 or carbon dioxide + water = glucose + oxygen

Question 4

What are the three types of photosynthesis?

Answer 4

C3, C4 and CAM

Question 5

Process of C3 photosynthesis

Answer 5

• Carbon dioxide enters
• Gases are exchanged through open stomata
• Gas goes through Calvin cycle to produce sugar

Question 6

Process of C4 photosynthesis

Answer 6

• Carbon dioxide enters
• Gases are exchanged through slightly open stomata
• Carbon uptake by PEP carboxylase requires ATP
• Gas goes through Calvin cycle to produce sugar

Question 7

Process of CAM photosynthesis

Answer 7

• Carbon dioxide enters
• Gases exchanged at night through open stomata
• Carbon uptake by PEP carboxylase requires ATP
• Gas goes through Calvin cycle during the day as stomata closes
• Produces energy

Question 8

Advantages and disadvantages of C3 photosynthesis

Answer 8

Advantages: efficient use of ATP
Disadvantages: photorespiration
Examples: most plants

Question 9

Advantages and disadvantages of C4 photosynthesis

Answer 9

Advantages: water conservation
Disadvantages: energy requirement
Examples: sugarcane, maize and grass

Question 10

Advantages and disadvantages of CAM photosynthesis

Answer 10

Advantages: water conservation
Disadvantages: energy requirement and slow growth
Examples: pineapple, cacti, succulents

Question 11

Why is most maize grown in the UK used as fodder?

Answer 11

Because maize has minimum temperature of 10 degrees and so has to be harvested earlier

Question 12

Why are C4 crops grown in Africa and South America?

Answer 12

Because they have a higher max temperature

Question 13

How much does agriculture contribute to total greenhouse gasses?

Answer 13

Agriculture contributes to 13% and the whole food system contributes to 35%

Question 14

How do plants adapt to increasing temperatures?

Answer 14

• Stalks become longer
• Leaves shrink to save water
• Grow away from other plants to avoid weakness

Question 15

For each 1 degrees increase in temperature how much does yield change in crops?

Answer 15

• Maize: 6% decrease
• Rice: 3.2% decrease
• Wheat: 7.4 % decrease
  Percentages increase for night time temperature increase

Question 16

How does climate change effect crop growth?

Answer 16

Extreme weather events increase causing land use change, overgrazing, continuous cropping and soil erosion

Question 17

How can crops be protected from climate change?

Answer 17

• Pest and disease control
• Crop choice
• Improved germplasm
• Breeding for genetic variation

Question 18

How do livestock cope in weather changes?

Answer 18

Cold environments: thicker coats, smaller ears
Warm environments: thin coats, humps to store fat and water

Question 19

Temperature zones

Answer 19

Grass based systems for cattle and sheep and free-range movement for pigs and poultry

Question 20

Arid zones

Answer 20

Pastoral systems (moving animals around for food and water) and nomadic lifestyle

Question 21

Equatorial zone

Answer 21

• Variation in size of producers
• Increase use of hybrid genetics
• Consistent warm temperature

Question 22

What are the thermoneutral zones for animals?

Answer 22

• Cattle (dairy): 5-25°C
• Cattle (beef): 0-25°C
• Sheep: 21-31°C
• Goat: 10-20°C
• Poultry: 15-23°C
• Pigs: 10-21°C

Question 23

Why is heat stress bad for cattle?

Answer 23

Worse milk yield

Question 24

How can heat stress be avoided?

Answer 24

More energy dense diet to increase body weight and milk yield and providing cattle with shade to lower body temperature

Question 25

How can livestock contribute less to climate change?

Answer 25

• Mixed crop-livestock system can be used to use less land
• A sustainable diet with plant protein
• Efficient systems to prevent long emissions of greenhouse gases