Term
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Definition
| generating lift(positive bouancy), no lift and fish sink (negative bouyancy)..their density is greater than water |
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Term
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Definition
| lift (positive bouyancy) generated during movement |
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Term
| Dynamic lift: how it is done |
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Definition
| pectoral fins of sharks and tuna:lifting foils; heterocercal tail of sharks:lift at caudal end; some fish hover by driving h2o down w/pectoral fins |
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Term
| Dynamic lift: considerations |
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Definition
| high energy expendature; have to maintain certain speed to work |
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Term
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Definition
| fish that have to swim anyway; bottom dwellers that dont have to swim often |
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Term
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Definition
| positive bouyancy generated w/o muscular effort |
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Term
| Static lift: how it is done |
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Definition
| density of bone, cartilage and protein is close enough to water that storage of low-density materials might balance and produce neutral bouyancy |
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Term
| Static lift: storage of gas in bony fishes |
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Definition
| swimbladder(gas bladder); to be neutral: freshwater-gasbladders need to be 7% of body volume; marine-gas bladders need to be 5% of body volume |
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Term
| Static lift: storage of gas in bony fishes: Boyle's law |
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Definition
| in fixed amnt of gas, volume varies inversely w/pressure. lift that fixed amnt of gas(in bladder)provides is function of volume, amnt of water displaced. |
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Term
| Static lift: storage of gas in bony fishes: boyles law: how it works |
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Definition
| fxed amount of gas will provide less boyancy at greater depth. fish is neutral at 1 depth n goes deeper, it will be neg bouyant and will have to add gas to bladder to remain neutrally bouyant. volume changes most rapidly with depth in shallowest water |
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Term
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Definition
| mostly in sharks, rarely in bony fishes |
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Term
| Storage of fats and oils: squalene |
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Definition
| mostly in squaloid sharks, who have very large livers, and hover over bottom in vry deep waters. contributes bouyancy in other fishes:ratfishes, some bony fishes |
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Term
| Storage of fats and oils: wax esters |
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Definition
| in coelacanths. Latimeria swim bladder has lipids, no gas! |
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Term
| Storage of fats and oils: lipids |
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Definition
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Term
| Storage of fats and oils: advantage |
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Definition
| lift doesnt vary with depth |
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Term
| Storage of fats and oils: disadvantage |
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Definition
| regulation of bouyancy linked with metabolism, use of fuels. regulation of lipid metabolism may be complex |
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Term
| Reduction of dense materials |
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Definition
| reduced calcification of bones; reduced protein in muscles |
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Term
| Reduction of dense materials: advantage |
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Definition
| lift doesnt vary with depth |
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Term
| Reduction of dense materials: disadvantage |
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Definition
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Term
| Swim bladder: ancestral character: |
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Definition
| physostomous(primitive)swim bladder. |
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Term
| Swim bladder: ancestral character: pneumatic duct |
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Definition
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Term
| Swim bladder: ancestral character: gulp and burp strategy |
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Definition
| gulp air at surface and get down to depth. burp when need to reduce bouyancy(when shallower depth desired) |
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Term
| Swim bladder: ancestral character: limitations of physostomes |
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Definition
| difficult to maintain neutral bouyancy at any depth, bc would have to gulp very large amoutn of air at surface. some dont gulp(gas secreted into swimbladder physiologically)so physostomous bladders in deep dwelling fish |
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Term
| Swim bladder: derived condition: |
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Definition
| physoclistous swim bladders |
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Term
| Swim bladder: derived condition: larval swim bladders |
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Definition
| initally physostomous, for first inflation. then inflation by secretion at gas gland, resorption at oval window. gas usually o2. |
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Term
| Swim bladder: derived condition: how does gas gland work |
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Definition
| secretion of gas against pressure gradient:high conc and partial press of gas inside bladder.blood lead to/frm gland runs through rete mirabile.afferent and efferent flows in opposition and close together:counter current multiplier. |
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Term
| Swim bladder: derived condition: oxygen in blood carried by hemoglobin |
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Definition
| cells in gas gland release lactic acid, countercurrent maintain gradient of high acid and low pH towards gland. low pH:O2 unloaded into plasma by Hb, increasing partial pressure. diffusion into swim bladder |
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Term
| Swim bladder: derived condition: resorption: guanine |
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Definition
| most of bladder lined with gauanine to prevent diffusion back out of swim bladder |
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Term
| Swim bladder: derived condition: resorption: oval window(body) |
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Definition
| passive diffusion back into blood here, controlled by bloodflow |
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Term
| Swim bladder: derived condition: resorption: oval body(valve) |
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Definition
| made of 2 muscles types:circular and radial. circular relaxed, radials contract and it streches swimbladder, increases furface area for diffusion.radial relaxes, circulars contract swimbladder no longer incontact w/oval body.gas remains in swimbladder |
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Term
| Swim bladder: derived condition: Limitation of physoclists |
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Definition
| powerful constraint on upward movement.swimbladder rupture if ambient pressure reduced too rapidly. |
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Term
| Swim bladder: derived condition: limitation of physoclists: rates |
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Definition
| most fish can compensate rates of about 1 meter/hr depending on depth and temp.faster fish(billfish,bluefish) about 3meters/hr. may explain physostomous bladders in deep-dwelling fishes, who rise to surface at night to feed |
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Term
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Definition
| escoidae(physostomous); cyprinidae(physostomous); percidae(physocistous) |
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Term
| swim bladders primitive: psysostomous condition |
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Definition
| primiterely connected to gut by pneumatic duct |
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Term
| swim bladders derived: physoclistous condition |
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Definition
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Term
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Definition
| gas gland=location of action in wall of swim bladder. pry O2 molecules from hemoglobin molecules in gas gland. accumulate enough O2 in solution in blood plasma |
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Term
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Definition
| produce sound; sound reception (weiberian apparatus) |
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Term
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Definition
| fish=ectotherms; body temp is that of environment; each species has particular range of temp that they can tolerate and thats optimal. poikilotherm:body temp varies with environment temp |
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