BIO202H5 Lecture Notes - Lecture 45: Euprymna Scolopes, Pupa, Ecdysone
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Mutualistic relationship with bacteria (bacteria colonize specialized organs in the squid, while the predatory squid can blend in with the environment and thus improve camouflage when catching prey) Metabolic processes in bacteria allow the squid to be camouflaged in its environment. If juvenile hormone levels are low: larva/pupa adult. Juvenile hormone triggers what stage of life the insect is in. Threshold le(cid:448)els of ju(cid:448)e(cid:374)ile hor(cid:373)o(cid:374)e; (cid:449)he(cid:374) it"s i(cid:374) the (cid:373)iddle you"re goi(cid:374)g fro(cid:373) lar(cid:448)a to pupa, a(cid:374)d if it"s really lo(cid:449) you"re goi(cid:374)g fro(cid:373) pupa to adult. Bombyxin stimulates release of steroids: has a positive feedback system on ecdysone (it encourages moulting, ensures that the animal grows enough between each moulting stage. Myosupression inhibits ecdysone to prolong larval stage: ensures that moulting does(cid:374)"t occur too fast. Which external cues trigger moulting: temperature changes (cyclicity of season changes, moisture of the environment and ion content, light (amount of daylight, pheromones released by other animals.
