Term
| More energy is harvested using this type of metabolism |
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Definition
| aerobic rather than anaerobic |
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Term
| Oxygen uptake: Capture by diffusion |
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Definition
| requires thin separation b/w environment and blood; requires large surface area; respiratory surface must be moist; must be continual renewal of blood and environment |
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Term
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Definition
| capture by diffusion -> uptake by respiratory pigment(Hb to HbO2) -> transport to tissues by blood -> unloading of oxygen from pigment -> movement into tissues by diffusion -> diffusion always required, respiratory pigment, transport systems etc may not be used in some animals |
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Term
| Why is an important limiting factor in gas exchance the gas content of water |
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Definition
| concentration of gas in water is lass than in air; water 800x more dense, more viscous, so takes more energy to renew water at respiratory surface than air; diffusion of gas in h2o much slower, diffusion distances need to be minimized for aquatic resp. organs; gas solubility affected by temp and salts in h20 |
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Term
| Problems a fish faces with respiration |
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Definition
| solubility of o2 decreases as temp increases; metabolic rate(demand for o2) increases as temp increases --> at warm temps, fish need to extract more 02 from less |
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Term
| Fish respiratory system must do this to solve problem |
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Definition
| extract o2 from environment w/low concentration of o2 -> deliver high concentrations of o2 to tissues w/in body -> extract o2 from h2o and move AGAINST concentration gradient into body and distribute to tissues |
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Term
| Basic respiratory organ: none |
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Definition
| gas transport by diffusion |
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Term
| Basic respiratory organ: lung |
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Definition
| body surface turned in or invaginated; fluid must move in and out- bidirectional flow; bc water is costly to move, rare in aquatic organisms |
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Term
| Basic respiratory organ: gills |
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Definition
| body surface is evaginated; water can flow past gill in unidirectional flow |
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Term
| Hagfish gill and gillcavity (gill tissue in multiple pouches with each individual opening to pharynx inside) |
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Definition
| some single opening to outside, others multiple; h2o drawn into nostril by moevement of velum; water pushed out of gill opening |
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Term
| Lamprey gill and gillcavity (gill tissue in multiple pouches with each individual opening to pharynx inside) |
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Definition
| multiple openings to outside; branchial cartilage outside gills; muscular contraction of cartilage pumpes out h2o; relaxation, expansion of branchial basket draws h2o in |
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Term
| Sharks and rays gill and gillcavity |
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Definition
| h2o flows into buccal chamber; h2o flows through multiple branchial (gill) chambers; each chamber separated from others by septum; multiple external gil slits (5); gill arch supports gill lamellae and septa; arch is medial(inside) gills |
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Term
| Bony fishes gill and gillcavity |
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Definition
| h2o flows into buccal chamber; 4 gill arches per side; reduction or absence of septa; lateral to gills is opercular chamber coveres by operculum or gill cover |
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Term
| Bony arch is part of bony fish gill and contains |
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Definition
| primary lamellae, secondary lamellae, and afferent(blood coming in) and efferent(blood leaving) arteries |
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Term
| Primary lamellae orientation |
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Definition
| lateral and medial set on each arch; close contact b/w lamellae adjacent on an arch; muscles associated w/ arches hold together tips of lateral lamellae against tips of medial lamellae from next anterior gill arch so h2o flows through curtain of gill tissue |
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Term
| Seconday lamellae orientation |
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Definition
| like little fins projecting from surface of primary lamellae; many secondary lamella per primary lamella, top and under; real close contact |
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Term
| Water flow over gills of bony fishes and cartilagenous fishes is: |
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Definition
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Term
| unidirectional flow over gills: |
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Definition
| 2 valves at mouth and operculum; water flows; action of valve and of other muscles in head function to maintain steady unidirectional flow over gills |
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Term
| Process of unidirectional water flow over gills |
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Definition
| mouth slightly opens, opercular valve closed; buccal cavity expands and water flows in; opercular cavity expands and water flows past gills; mouth closes and opercular valve opens; cavities contract and water is expelled out gill opening |
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Term
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Definition
| into afferent branchial arteries -> lamellae -> leaves lamellae and exits via efferent branchial arteries |
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Term
| Direction of bloow flow through lamellae |
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Definition
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Term
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Definition
| out along a primary lamella, through secondary lamella; back along primary towards gill arch |
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Term
| Direction of blood flow in decondary lamella |
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Definition
| direction opposite to flow of water; countercurrent exchanger: extraction efficiency up to 80% |
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Term
| Problem: cost of breathing |
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Definition
| high density and viscosity of h2o means it takes energy to ventilate; branchial pumping 10-15% total energy |
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Term
| Individual adjustments to cost of breathing problem: When Oxygen demand increases individual can breathe more often |
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Definition
| this increases ventilatory frequency (increase cost of pumping) |
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Term
| Individual adjustments to cost of breathing problem: When Oxygen demand increases individual can take bigger gulps |
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Definition
| increases stroke volume (increase cost of pumping) |
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Term
| Individual adjustments to cost of breathing problem: When Oxygen demand increases individual can recruit more secondary lamellae |
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Definition
| lamellae at tips recieve less h2o flow and blood flow; as h2o flow increases over gills, tips recieve more flow; blood flow increases to tips, higher blood pressure and dilation of afferent arterioles |
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Term
| Individual adjustments to cost of breathing problem: Ram ventilation |
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Definition
| open mouth and opercular cavity at same time and swim; circumvents problem of high cost breathing when active;transfers work of ventilation to locomotory muscles |
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Term
| Individual adjustments to cost of breathing problem: Ram ventilation seen in |
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Definition
| active fishes in rapidly-flowing h2o:salmonids; active ocean fishes:mackerels, some oceanic sharks, need to swim to breathe |
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Term
| Breathing strategies diverse among species; active fishes have: |
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Definition
| reduced thickness of secondary lemallae; increased # secondary lamellae per mm of primary lamellae; relatively large gill areas |
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Term
| Auxiliary respiratory structure: skin |
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Definition
| diffusion of oxygen from water into dense network of capillaries in skin (eels) |
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Term
| Auxiliary respiratory structure: swim bladder |
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Definition
| vascularized physostomous swim bladders (gars) |
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Term
| Auxiliary respiratory structure: lungs |
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Definition
| modified swim bladder (lungfish) |
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Term
| Auxiliary respiratory structure: mouth |
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Definition
| vascularized region in roof of mouth (electric eel) |
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Term
| Auxiliary respiratory structure: gut |
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Definition
| vascularized stomach or intestinal wall (armored catfish) |
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Term
| Air Breathing: Facultative |
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Definition
| capable of adapting to diff conditions (lepisosteus) |
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Term
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Definition
| cannot adapt to diff conditions (protopterus) |
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