ENDOCRINE SYSTEM

consists of those glandular cells, tissues, and organs whose products (hormones) supplement the rapid, short-term coordinating functions of the nervous system.

HORMONE chemical signal sent from cells in one part of an organism to cells in another part (or parts) of the same individual Chemical messenger Produced in very small quantities, but cause big changes in their target cells.   effect may be stimulatory (pencetus) or inhibitory (perencat).  

Four (at least) categories of hormone-producing cells in insects: 1) Endocrine glands -- producing hormones and releasing them into the circulatory system. 2) Neurohemal organs -- store their secretory product in a special chamber until stimulated to release it by a signal from the nervous system (or another hormone). 3) Neurosecretory cells -- specialized nerve cells (neurons) that respond to stimulation by producing and secreting specific chemical messengers.  - a link between the nervous system and the endocrine system 4) Internal organs -- hormone-producing cells are associated with organs like ovaries and testes, the fat body, and parts of the digestive system

1) Endocrine glands the largest glands are found in the prothorax: PROTORACIC GLANDS (A) Produce ecdysteroids/ molting hormones(ECDYSONE) stimulate synthesis of chitin and protein in epidermal cells for MOULTING PROCESS Once reaches adult stage, its prothoracic glands wither (kering/kecut): never molt again. (A) (A)

2) Neurohemal organs 1) CORPORA CARDIACA (B) 2) CORPORA ALLATA (C) Release prothoracicotropic hormone (PTTH) Only release PTTH when received signal from brain 2) CORPORA ALLATA (C) manufacture juvenile hormone (JH), Inhibits(merencat) development of adult characteristics during the immature stages promotes sexual maturity during the adult stage. (B) (C) (B) (C)

Neurosecretory cells (D) found in clusters, both medially and laterally in the insect's brain. specialized nerve cells (neurons) that respond to stimulation by producing and secreting specific chemical messengers.   Functionally, they serve as a link between the nervous system and the endocrine system   secrete brain hormone (D) (D) (D)

4) Internal organs Ovaries and testes produce gonadal hormones: to coordinate courtship and mating behaviors.   Ventral ganglia in the nervous system eclosion hormone that helps an insect shed (tanggal) its old exoskeleton bursicon: that causes hardening and tanning of the new one.  

CHEMICAL COMMUNCATION IN INSECTS (SEMEIOCHEMICAL)

3 modes of communication: Acoustical: produce sounds Visual Chemical: MOST IMPORTANT

chemicals that mediate interactions between organisms Intraspecific: SEMIOCHEMICAL chemicals that mediate interactions between organisms Intraspecific: pheromones btw two members of same species Interspecific: allelochemicals btw 2 members from different species

INTRASPECIFIC (PHEROMONES) 2 types of pheromones i) Primer pheromones Slower to act: physiologically alter (ubah) endocrine and reproductive system Eg: queen pheromones pheromone secretions of the queen honey bee (Apis mellifera) are partially responsible for the inhibition of worker ovary development (become sterile) so no new queen is produce

ii) Releaser pheromones Immediate response (nervous system)

RELEASER PHEROMONES i) ALARM PHEROMONES ii)SEX PHEROMONES Common in social insects When threaten or injured: alarm other members to disperse ii)SEX PHEROMONES Attract males & females iii)AGGREGATION & RECRUITMENT PHEROMONES ants: lay trails, lead to food bark beetle: aggregate to attack the tree bark

iv) IDENTIFICATION v)SPACING to recognize members of same sp. eg: colony odor in honey bees: strange worker from diff. colony killed v)SPACING as repellents/deterents eg: parasitic wasp: release spacing pher. on parasitized eggs

vi) FUNERAL PHEROMONES to make sure nests are kept clean alien and dead objects immediately removed too large, seal them in tomb

INTERSPECIFIC (ALLELOCHEMICALS) 2 types: i) allomones emitted by one member of sp to a member of diff. sp, favourable to the emitter (penghasil chemical) eg: stink bug released chemicals, delivered to predator

ii) kairomones released by a member of 1 sp, but favorable to the recipients of another sp eg; human emit lactic acid, attract the mosquitoes (favor to the mosquitoe)

any of various internally secreted compounds formed in endocrine glands, that affect the functions of specifically receptive organs or tissues when transported to them by the body fluids. any chemical substance released by an animal that serves to influence the physiology or behavior of other members of the same species. any chemical substance released by an animal that serves to influence the behavior of other species