Food supply, plant growth and productivity 3.1 Flashcards
What is food security
The ability of human populations to access food of sufficient quality and quantity
What is sustainability
Doesn’t degrade natural resources upon which agriculture depends
What are the 3 aspects of food security
Quantity, Quality and Access
What does Quantity mean
Sufficient food must be available at all times
What does Quality mean
Food is sufficiently nutritious and barked to provide a balanced diet
What does Access mean
People have economic means to obtain the available food
What does agricultural production depend on
Factors which control photosynthesis and plant growth
What does increasing food production depend on
Breeding higher yielding cultivars; improving characteristics to aid rearing and harvesting; using fertilisers (N P K); protecting crops from pests, disease and competition
What are the ways energy is lost from a food chain
Heat, movement, undigested food and waste
What is light
Form of electromagnetic radiation which travels in waves
What are wavelengths
the distance between 2 crests on a wave and is measured in nanometers (nm)
What are the 3 things light does after contact with a substance
Absorbed, transmitted or reflected
What colours on the spectrum does chlorophyll absorb
Violet, blue and a bit of red
What are the main pigments in a leaf
Chlorophyll a, chlorophyll b and the carotenoids (carotene and xanthophyll)
What is an absorption spectrum
Shows the absorption of light of each wavelength by each pigment
