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CH1012
ALKENES
Alkenes are very important in industry and biology.
Ethene
> 20 x 106 ton/yr
Muscalure  (pheromones)
housefly sex attractant
b-carotene
Carotenes found in
green plants when
ingested are precursors to vitamin A
Bound to a protein this
isomerises reversibly in
the eyes
Retinol is turned into retinal and bound to opsin to make rhodopsin the visual pigment.