Download keywords from past papers q1

Carrying capacity
Transgenics/ genetic engineering
Heterotrophic nutrition
The maximum population that can be
sustained/supported sustainably
Genetic modification by the transfer of genes into
a different species
Gaining food energy from other living organisms
Mulch(ing)
The control of weeds by adding shredded
vegetable matter to the soil surface
Polyculture
The growth/cultivation of more than one
crop/species grown in an area (together)
Steroid hormones
Productivity
Agrochemicals used to increase the Gross Growth
efficiency of livestock
Yield per unit area
Changes in society that meet the needs of the
Sustainable development/ sustainability current generation without reducing the ability of
future generations to meet their needs
Efficiency
Limiting factor
Gross Growth Efficiency
Yield per unit input. A measure of an output
compared with the level of input.
a variable whose shortage of availability prevents a
process occurring more rapidly. The factor in
shortest supply/minimum (which controls the
process)
the increase in body mass per unit of food eaten
Growth Rate
the increase in body mass per unit time
Productivity
the amount produced per unit area
Abiotic factor
physical environmental condition
Intensive agriculture
high yields are achieved by using large inputs on a
small area
Extensive agriculture
spreading inputs over a large area produces a low
yield per unit area, but increases total yield
Maximum sustainable yield
Pollution
The maximum allowable harvest that will not
change the ability of the resource to supply that
harvest indefinitely
Energy/matter/chemicals (released into the
environment with the potential to cause) adverse
changes/damage to an ecosystem/environment
Overpopulation
Excess of population over resources/ carrying
capacity
Agroecosystem
The living organisms/biota and physical
processes/abiota and their interactions/which are
(human) controlled in a (artificial)
farming/agricultural ecosystem
Monoculture
(repeated) growth of a single crop (over a large
area/long time)
Cross breeding
Mating (parents of two) different breeds/varieties
to produce (offspring with desired/different)
combinations/characteristics [R species]
Vegetative propagation
Asexual reproduction/production of offspring that
are genetically identical to parent/clone from
named/plant tissue/micropropagation (eg
corms,bulbs/runners/ rhizomes/cuttings)
Agricultural diversification
Increase in the variety of activities on farms
Energy subsidy
The (artificial/additional) named/energy
inputs/fossil fuels/machinery/fertilisers /pesticide
/antibiotics (into production systems)
By-catch
Non-target/unintended/accidental/species caught
by fishing/over quota