Exam II Review- Hormones are used as triggers to start a series of irreversible events- Elytra: hard coverings on wings- Brain secretes PTTH/brain hormone and Allatotropin- Neurosecretory cells: brain (head) & ganglia (thorax and abdomen)- Prothoracic gland (head and prothorax) – molting hormone- Corpora Allata – neck; releases juvenile hormone (JH)- Ovaries and testes located in abdomen- Apolysis: separation of old cuticle from epidermis - Ecdysis: escape for old exoskeleton (exuvial (cast skin))- Metamorphosis: o Ametabolous: ametamorphosis = no metamorphosis No significant changes Egg  nymph  adulto Hemimetabolous: incomplete [aquatic] Incomplete Egg  naiads  adulto Paurometabolous: gradual [terrestrial] Gradual Egg  nymph  adulto Holometabolous: complete Complete Eggs  larvae  pupa  adult E.g. butterfly- KNOW ORDERBrain  brain hormone (PTTH)  prothroacic gland  ecdysone  epidermal cells  molt- When JH is high, ONLY juvenile forms may occur- When JH is below threshold, next stage (instar) will be an adult form- Edgar Allen Poe = poet- Symbols of fertility because fast generation times/reproductive ratesSexual Reproduction:- Reproduction that involves two gametes; bi-parental- Mating: copulation- Direct sperm transfer is the mot efficient delivery of sperm to egg – reduces environmental influence and competition- Hermaphroditic: insects with both male and female organs in the same body- Advantage: diversity, survival, genetic information from both parental units- Disadvantage: male selection, location (complex), takes time energy and resources- Lock & Keyo Female shows “sales resistance”o Male shows “salesmanship”Asexual Reproduction:- No sharing of gametes- Advantage: successful process, allows species to take advantage of new opportunities, used in disruptive environment- Disadvantages: only ½ of genetic variability is present in population, genetically similar individuals susceptible to disaster- Parthenogenesis: asexual reproduction; development of an embryo without fertilization- Haplodiploidy (arrhenotoky = males)- Thelytoky (alteration of generations = female)- Autosomes - any chromosome other than a sex chromosome- Female: XX Male: XY- Lepidoptera – Female: XY Male: XX- Hypemenoptera: Female: XY Male: XO- Sexual Attractionso Sighto Soundo Temperatureo Chemicals/odors- Insects are among the most prolific animals to ever inhabit the earth- Reproductive processes are effective, efficient, and interesting- The “lock and key” determines mating potential- Insects must find resources in order to surviveo Food, shelter, water, favorable environment, others of the same species (reproduction)- Trail pheromones (chemical odors to locate)- Aposematic coloration (genetic)- Camouflage (behavioral)- Inter-specific: not the same species; cannot mate- Intra-specific: same species, can mate within species- How sound is made:o Tympanic membraneo Stridulation (rub parts to make sound)o Rustling of body partso Air movement- Hormones = small proteins that cause large changes in insects; used for chemical information transfer produced in specialized glands/both male and female- Allelochemicals: produced by one organism to illicit a response from an organism of a different species; inter-specifico Allomones: “all about me” – advantage to SENDING organismo Kairomones: “karing for you” – advantage to RECEIVING organismo Synamones: shared advantage between species, BOTH benefit- Adaptations of insects to overcome/adjust to adversityo Fly, make substances, cover in waxes, blend, taste bad- What factors limit growth of population?o Temperature, humidity, rainfall, and disease- Nymph/naiads = shelter tubes, webbing, rolled leaves, etc.- Crypsis: GENETIC; industrial melanism; colors/patterns match background- Homotypism: resemble something edible- Camouflage: BEHAVIORAL; resembles background/substrate- Mimicry: resemble something toxic or unlikely to be eateno Aposematic coloration = genetic- Thanotosis: playing dead like a possum- Startle response: sudden response – e.g. butterfly with eyes on wings- Reflex bleeding: blood chemicals released when bitten e.g. grasshoppers- Diapause: periods of inactivity – don’t come out of it; preparing for cold conditions- Cryptobiosis: no visual signs of life; freeze dry – can come out of it- Walking, running, jumping, swimming, etc. = forms of movement- Evolution of flight muscleso Direct – move wings; butterflieso Indirect – move thorax rather than wingso *Halteres – 2nd set of wings, nub- Trivial flight: short distances (foraging (food) or mating)- Migrations: to a better environment; within boundaries of layers of the earth (15ft); outside boundary layers (5,000 ft); one-way migration; “return migrations”monarch; migration’s are more common in unstable environmentsInsect Movement Patterns- Reflex: undirected movement, simplest behavior, doesn’t involve CNS- Taxis: directed movemento Menotaxis: partial or indefinite orientation (wander)o Astrotaxis: uses sun, moon, or stars to navigateo Phototaxis: positive/negative response to light- Insects are major nitrogen recyclers- Lac: provides protection against parasites- “Shell-lac”: “stick-lac”; used to protect furniture- Cochineal: red juice type stuff, grows on prickly cactus’- Mannipara (manna): biblical reference, scale insects and aphids that feed on tamarisk bushes – produces honeydew (manna)- Gall: abnormal growth on plants (cancer) due to insect feeding and egg depositiono Declaration of Independence written in gall-ink- Insect saliva = silk- Why is silk so expensive?o One dress = 1 lb. of silko 1 lb. = 1,700 cocoons- *Genus and species of honeybeeso Genus: Apiso Species: mellifera- Sericulture: the culturing of silkCastes of Bees- Workers (X/Y)o All females – fertilized eggso Polyethism: duties correlated with age Young adult females are nurses Older females are foragerso Duties: Nurse: feed larvae Maintainence of colony: build comb/clean colony Foragers: leave colony and bring back pollen/nectar Defense (stingers)…of Queen/colony (stings but dies)o Communications Dance Odors Sound (pitch) *Pheromones – who produces them?- Queenso Reproductive female X/Y XO = drones XY = femaleo Eggs laid by Queen, many queens formed in absence of QUEENo Royal jelly (specific food resource) – prepared by workers, feed to larvaeo