ABBOTTSCOLLEGE 1 Page 87

ROLES OF THE INVERTEBRATES 2 PollinationDecompositionSoil aeration Page 87

POLLINATION 3  Is the transfer of ripe pollen containing the male gametes from the anthers to the stigma to allow for fertilization PAGE 87

IMPORTANCE OF POLLINATION 4 Without pollinators: Natural ecosystems would collapse Agricultural production would be badly affected and humans would be short of food

DEFINITIONS 5 Pollinator = animal that moves the pollen Polleniser = the plant from which the pollinators get their pollen

BEST INSECT POLLINATORS 6 ButterfliesMothsAntsFliesBeetlesBees

BEES 7 Most of their life is spent collecting pollen Honey bee is the most commonly used agricultural pollinator

CROPS POLLINATED BY INSECTS 8 Fruit cropsVegetables Oilseed crops Nuts Coffee and cocoa

PROBLEMS 9  Bee populations are declining  Fields/orchards and monocultures have led to crops needing managed pollination  Pollination management involves agricultural practices that ensure the pollination of a crop so that the yield and quality of the crop is improved  Often involves commercial beekeepers becoming pollination contractors and transporting the bees to areas where they are needed

MONOCULTURE 10 Monoculture is the agricultural practice of producing or growing a single crop or plant species over a wide area and for a large number of consecutive years.agricultural It is widely used in modern industrial agriculture and its implementation has allowed for large harvests from minimal labour.industrial agriculture DEFINITION

DECOMPOSITION 11 Is a biological process that includes the physical and chemical breakdown of complex organic molecules of dead material into simpler organic and inorganic molecules It is brought about by invertebrates and micro- organisms PAGE 88

INVERTEBRATES 12  Beetles, slugs and worms feed on organic material, breaking it down  They break down plant litter (dead roots, leaves and grasses) = detritus  A complex stable organic material called humus is formed  Which improves the texture of soil and adds nutrients to it

MICRO-ORGANISMS 13 Complete the breakdown process of organic matterNitrogen, phosphorus and sulphur are released into the soil

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SOIL AERATION 15 Earthworms feed on detritus which they drag down into their burrows Burrowing improves soil drainage by creating passageways for air and water Worms excrete casts Worms work as pistons forcing air through the tunnels and aerate the soil Tunnels also allow roots to penetrate into the soil PAGE 89

16 Vermicast, also called worm castings, worm humus or worm manure, is the end- product of the breakdown oforganic matter by an earthwormorganic matterearthworm DEFINITION

TO DO 17

TO DO 18 LEARNING ACTIVITY 11 PAGES 90 – 92 SHORT QUESTIONS

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