BIOL 3454 1nd Edition Lecture 17I. Communication a. Lots of studies on squid and octopusb. Visual signals extremely important c. Body motions and color changes through chromatophoresd. Ink from and ink gland for defenseII. Reproduction a. Sexes separate b. One arm of adult males modified in to a hectocotylus – plucks the spermatophore (sperm packet) and insert into female mantel cavity III. Cephalopod taxonomy - Nautiloideaa. One pair of gillsb. Only one surviving genus with 5 speciesIV. Cephalopod taxonomy - Ammonoideaa. All extinct in the certaceous b. Extinct before the asteroid impactc. Chambered shwlls with more developed septa than nautiloidsV. Cephalopod taxonomy – Coeloideaa. Everything extant besides Nautiloidea b. Vampire squid and vampire octopus (don’t know which)VI. Class Bilvalvia (Pelcopoda)a. Hatchet footed animals – nick namedb. Mussels, clams, scallops, oysters, (shipworms)c. Sedentary filter feedersd. Marine and freshwatere. Very important to humans for food consumption f. Bivalve shell form and function i. 2 shells held together by inge ligament ii. Umbo – oldest part of the shell growth emanates from it iii. Pearl form when foreign objects lodges between mantle and shell g. Body, mantel and locomotion i. Visceral mass suspended from dorsal midline ctenidia hand on each side of footii. Some clams have a mantel modified into long siphons iii. Most push foot between valves muscles contract for movement extra blood increases size to be an anchor into substrate iv. Scallops and file shells swim by pushing water out of the mantle edge forcefully h. Gills and feeding i. Gas exchange occurs in both mantle and gills ii. Some have modified these gills through lengthening of filaments can interlock toform lamellaeiii. Most bivalves filter feeders (respiration brings both food and gas exchange)These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.iv. One group (shipworms or termites of the sea) bore into and eat wood – very damaging i. Internal structures i. Floor of most folded into ciliary tracts ii. Particles sorted nonfood excreted, food directed to digestive gland or engulfed by amebocyteiii. Style sac has a crystalline style and whirls by ciliary action keeps digestive processes moving iv. 3 chambered heartsv. 2 u-shaped kidneysvi. 3 pairs of ganglia separate from each other vii. Sense organs poorly developed – some have decent eyesj. Reproduction i. Sexes separateii. Gametes usually discharge into water iii. Glochidium – specialized veliger (larvae)iv. Some females hold glochidia in a specialized pouch called conglutinate specific shape for each speciesk. Class Scaphopodai. Tusk shells or tooth shells one piece tubular shell conical at both ends ii. Benthic from shallow to 6000m deep iii. No gills iv. Have long feeding tentacles with ciliated knobs called captacula v. Radula carries food to gizzard vi. No eyes sensory tentacles or osphradia vii. Sexes separate trochophore larvaeVII. Test: ancestral molluscs look like? What direction did molluscs go? (shell, no shell, brains, fast)VIII.Chapter 17: IX. Annelids and Alliesa. Coelomate prostoomes b. Coelom through schizocoely c. Spiral mosaic cleavage d. 3 phyla – annelida, Achiura and SipunculaX. Phylum Annelidaa. Latin root annelus (little ring)b. Earthworms, leeches, polychaete wormsc. Divided into segments called metameresd. Division into segments called metamerism e. Rings called annuli f. Some have chitinous bristles called setaeg. World wide almost all habitats h. Characteristicsi. Unique head, parapodia ancestral ii. Bilateral symmetry – triploblastic iii. Epithelium secretes moist cuticle iv. Digestive system complete and not segmented v. Asexual reproduction by fission and fragmentationvi. Typically a pair of kidney like organs per segment for waste removal vii. Closed circulatory system i. Basic body plan i. Usually 2 two part head, a prostomuom and a peristomium ii. Terminal portion called a pygidium iii. New segments just in front of the pygidium (older at the front)iv. Each segment usually with its own circulatory, respiratory, nervous and excretorystructuresv. Exceptr for leeches coelom filled with fluid to make a hydrostatic skeleton XI. Class Polychaetaa. Greek poly – many/chaite =long hair b. Most marine c. Up to 3m long d. Live under rocks in crevices shells in sediment a few planktonic e. Significant component of marine food chains f. Form and function i. Differentiated head with food sense organs, paired parapodia on most segmentsii. Many setaeiii. Usually divided into sedentary and mobile forms iv. Postomoum sometimes retractile, holds eyes, tentacles sensory palps v. Peristomium surrounds mouth has setae palps and chitinous jaws in predatory forms vi. Forefut, midgut and hindgut vii. Mobile species scavengers or predators sedentary species usually filter feedersviii. Parapodia and gills for gas exchange some small species just use diffusion across body wall ix. 3 types of kidneys depending on speacies protonephridia, metanephridia or a mix x. Nephrostome opens into coelom xi. Double ventral nerve cord xii. Possess eye, statocysts nuchal organs xiii. Everything from simple eyespot to eyes with good visual acuity and complicated structures (lens and cornea)xiv. Nuchal pits chemoreceptivcexv. Usually no permanent sex organs uslaly separate sexes xvi. Gonads temporary swlling gametes shed into coelom xvii. Fertilization external larvae called