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207 Cards in this Set
- Front
- Back
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Shark Taxonomy |
Phylum Chordata Sub-phylum Vertebrata Class Chondrichthyes Sub-class Elasmobranchii Super-order Euselachii |
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Ray Taxonomy |
Phylum Chordata Sub-phylum Vertebrata Class Chondrichthyes Sub-class Elasmobranchii Super-order Batoidea (skates, rays, guitarfish) |
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Order Pristiophoriformes |
sawsharks Fam Pristiophoridae- saw sharks |
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Order Squantiniformes |
angelsharks- look like rays but gills on side of body not underneath Fam Squantidae- angel sharks |
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Order Squaliformes |
dogfish Fam Echinorhinidae- bramble shark Fam Squalidae- dogfish Fam Centrophoridae- Gulper shark Fam Etmopteridae- lantern sharks Fam Somniosidae- sleeper sharks Fam Oxynotidae- rough sharks Fam Dalatiidae- kitefin sharks |
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Order Hexanchiformes |
six-gilled sharks, some have 7 Fam Chlamydoselachidae- frilled shark Fam Hexanchidae- cow shark |
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Lamniformes |
mackerel sharks Fam Mitsukurinidae- goblin shark Fam Odontospididae- sand tiger shark Fam Pseudocarcharhiidae- crocodile shark Fam Megachasmidae- megamouth shark Fam Alopiidae- thresher sharks Fam Cetorhinidae- basking sharks Fam Lamnidae- mackerel sharks- white, mako, porbeagle |
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Order Carcharhiniformes |
Ground sharks/ requiem sharks |
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Order Orectolobiformes |
Carpet sharks Fam Parascyllidae- Collared carpet shark Fam Brachaeluridae- blind shark Fam Orectolobidae- wobbegong shark Fam Hemiscylliidae- long-tailed carpet shark Fam Ginglymostomatidae- nurse shark Fam Stegostomatidae- zebra shark Fam Rhincodontidae- whale shark |
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Order Heterodontiformes |
Bullhead sharks Fam Heterodontidae- Bullhead sharks |
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Order Pristiformes |
Sawfishes- rays, flattened, gills ventral Fam Pristidae- sawfish |
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Order Torpediniformes |
Electric Rays- kidney shaped electric organ Fam Narcinidae- numbfishes Fam Hypnidae- coffin rays Fam Torpedinidae- torpedo rays Fam Narkidae- sleeper rays |
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Order Myliobatiformes |
Stingrays, have spines Fam Plesiobatidae- giant stingrays Fam Hexatrygonidae- 6 gill stingray Fam Urolophidae- stingarees Fam Potamotrygonadidae- river rays Fam Dasyatidae- whiptail stingrays Fam Gymnuridae- butterfly rays Fam Myliobatidae- eagle rays Fam Rhinopteridae- cownose rays Fam Mobulidae- devil rays |
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Order Rajiformes |
Skates- thorns on back Fam Arhynchobatidae- softnose skates Fam Rajidae- skates Fam Acanthobatidae- legged skates |
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Order Rhinobatiformes |
Guitarfishes Fam Rhibobatidae- guitarfish Fam Platyrhinidae- thornback rays |
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Fam Scyliorhinidae |
Cat sharks |
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Fam Proscylliidae |
finback cat shark |
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Fam Pseudotriakidae |
false cat sharks |
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Fam Leptochariidae |
barbeled hound shark |
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Fam Hemigaleidae |
weasel shark |
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Fam Triakidae |
Houndshark |
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Fam Carcharhinidae |
requiem sharks blacktip, spinner, silky, blacknose, dusky, bull, sandbar, oceanic whitetip, finetooth, tiger, lemon, atl sharpnose, blue |
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Fam Sphyrnidae |
Hammerheads bonethead, scalloped, great, winghead, smooth |
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Interrenal tissue elasmo |
Interrenal is anatomically distinct from renal and chromaffin tissue |
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Chromaffin tissue |
Functions in production of catecholamines Near interrenal gland and renal tissue |
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What do sharks have that teleosts don't? |
-Cartilage internal skeleton -5-7 gill slits -short ribs without true muscular attachment -No swim bladder, use liver -internal fertilization -rows of replaceable teeth -ceratotrichia in fins -placoid scales -vertebral column extends into caudal fin |
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tesserate mineralization |
Calcification of cartilage of some shark vertebrae on the surface of vertebrae (perichondral) |
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Mixopterygia |
Claspers of male elasmobranchs Modification of male pelvic fin Has spines and barbs to hold sharks together |
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Spiral valve |
Structure in intestine of elasmos that increases surface area to increase absorption. 1. true spiral 2. scroll 3. V's 4. inverted V's |
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Retention of urea and TMAO in sharks |
-increased internal solute concentration to be isoosmotic to hyperosmotic to env -helps with salt and water balance -only retain enough to keep balance |
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characteristics of subclass elasmobranchii |
- 5-7 gill slits -no tentaculum- clasper like organ on head -amphistylic or hyostylic jaw suspension -rapid tooth replacement -dermal denticles |
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Amphistylic jaw suspension |
Hyomandibular provides partial support posteriorly Tight anterior ligament attachment Modest gape |
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Hyostylic jaw suspension |
Hyomandibular provides complete support posteriorly Loose anterior ligament attachment Allows jaw to protrude |
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Types of caudal fins in sharks |
1. heterocercal- vertebrae extend into upper lobe of caudal 2. hypocercal- vertebrae extend into lower lobe of caudal- Squantiniformes 3. Diphycercal- vertebrae extend horizontally into upper lobe |
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Function of pectoral and pelvic paired fins |
Control pitch, up or down movement |
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Function of dorsal and anal fins |
Control horizontal stability Roll and yaw |
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Body type I |
Mackerels
Pointed, conical head cylindrical body large pectorals, small pelvics, 2nd and anal narrow peduncle with keels symmetrical caudal fin w high aspect ratio most efficient swimmer |
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Body type II |
Mustelids, lemon, night sharks Flatter head and body but still cylindrical large pectorals, mod pelvics, 2nd and anal narrow peduncle without keels asymmetrical caudal with low aspect ratio |
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Body type III |
Nurse, 7 gilled, chain dogfish sharks Blunt snout Anterior pelvics, posterior dorsal asymmetrical caudal with low aspect ratio lower lobe of caudal reduced or absent |
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Body type IV |
Squalids, cookie cutter, lanter sharks No anal fin Upper lobe of caudal fin large |
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Body type V |
Skates, rays, angelshark Dorsoventrally flat large pectorals reduced caudal fin |
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Integument |
Separates internal and external environments 1st line of defense and protection Supports accessory structures |
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Cellular glands |
Primarily mucus or venom Glands in skin that secrete mucus or venom |
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Neural crest cells |
Create mesenchyme for development of photophores, chromatophores, and scales |
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Describe the anatomy of a dermal denticle |
Enamel on outside, dentine on inside, pulp cavity inner Implanted in epidermis with base in dermis Crown is above skin surface |
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Function of dermal denticles |
1. Protect from predators and parasites 2. Protect from abrasion 3. Minimize hydrodynamic friction 4. Prey capture/manipulation |
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Bioluminescence in sharks |
Have photophores in epidermis that match down-welling light for countershading -Can be used for species recognition in schools -Can be used for prey attraction Present in family Etmopteridae and Dalatiidae |
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Mouth positions of sharks |
1. subterminal 2. terminal |
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Dental groove |
Contains replacement teeth and covered by dental lamina |
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Tooth replacement |
Anchoring tissue migrates anteriorly Some replace entire rows at one time Have about 250 teeth at a time but only 50 are in functional positions |
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Tooth structure |
Made of apatite crystals (calcium phosphate) Acellular bone Has pulp, dentine, enamel Not anchored in jaw but sits on fibrous tooth bed Root and Crown externally |
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Root of shark tooth |
External feature of shark tooth Associated with pulp of tooth |
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Crown of shark tooth |
External feature of shark tooth Filled with dentine and covered with enamel |
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Tooth structure and diet |
1. long thin pointed- slippery fish and squid- mako 2. serrated and triangular- cutting/sawing chunks of flesh- great white 3. flat millstone- grinding shellfish and crab- rays 4. many tiny teeth- plankton and small fish- whale |
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Functions for upper and lower teeth |
Upper are stronger and used for slicing Lower are curved and sharp providing grip |
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Spiracles |
Holes on dorsal side of head Water flows in to provide O2 to rest of body Common in bottom-dwelling species whose gills are often covered by sediment |
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Gills |
Allow exit of water from buccal cavity and oxygen exchange |
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Interdorsal ridge |
May direct the flow of water from the first dorsal fin |
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Cloaca |
Opening for urogenital ducts and rectum Spermatozoa and urine exit via urogenital papilla |
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Endoskeleton |
Protects internal organs Cartilaginous Made of collagen and elastin Suspended in matrix of salts and minerals |
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Advantages of cartilage |
1. flexibility- allows more maneuverability 2. lighter- more buoyant |
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2 parts of the skeleton |
1. Axial- Skull, vertebral column, and rib cage 2. Appendicular- pectoral and pelvic fins and their girdles |
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2 parts of the chondocranium |
1. Neurocranium- largest, anterior and dorsal, houses brain and associated sense organs 2. Splanchnocranium- posterior and ventral, supports jaws, gills, tongue, and pharynx |
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Shark vertebrae anatomy |
Dorsal neural arch with spinal cord Centrum with notochord Transverse process for rib muscle attachment Hemal arch in tail with caudal artery and vein |
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Basals of shark fins |
1. propterygium 2. mesopterygium 3. metapterygium Pectoral girdle with coracoid bar |
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Aplesodic pectoral fins |
-Radials extend 40-45% into fin -Distal portion of web supported by ceratotrichia -Flexible -Allows for "walking" -slow cruising pelagic/ benthic fish -Leopard, bamboo, dogfish |
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Plesodic pectoral fins |
-Extend over 60% into fin -Stiffer from radials -More support -Streamlined distal web to reduce drag -Fast swimming sharks -Lemon, blacktip, lamnid |
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Pelvic girdle |
Puboishiac bar connects fins Only has metapterygium and propterygium |
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Anguilliform swimming |
Entire trunk and tail participate in lateral undulations More than one wave Orectolobiformes, Chlamydoselachidae, Scyliorhinidae |
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Carangiform swimming |
Undulations confined to posterior half to 1/3 of body Less than one wave present Squaliformes, Carcharhiniformes, some Lamnids |
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Thunniform swimming |
Only tail and caudal peduncle participate Present in Lamnids- high speed cruisers |
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Red muscle |
Slow tonic fiber 20% muscle in sharks more blood circulation more mito, myoglobin slower contracting, small nerve fibers high oxidative enz, aerobic, low glycogen storage Cruising or continued slow activity |
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White muscle |
Fast twitch fiber 80% muscle in shark not much blood less mito, no myoglobin Fast contracting, large nerve fibers low oxidative enz, anaerobic, glycogen storage Burst swimming |
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Digestion |
Breakdown of food into usable products and waste |
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Opportunistic predators |
Eat whatever they can find |
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Elimination |
Process of removing feces from body |
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Mouth |
Teeth for grasping and holding prey |
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Pharynx |
Back of throat between gills, under spiracle Filter feeders pharynx covered in mucosa that traps plankton |
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Esophagus |
Long, broad tube connecting the mouth to the stomach Folds to help with digestion Peristalsis- wavelike contraction that forces food down esophagus, involuntary Has papilla that produce mucous and allow for swallowing |
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Body cavities |
1. Pleuroperitoneal cavity- everything but heart 2. Pericardial cavity- contains heart |
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Transverse septum |
Lining that separates the two body cavities |
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Stomach |
J-shaped with cardiac, main body, and duodenal regions Loose-walled and stretchy for expansion Mixes food contents and secretes gastric acid and pepsinogen for food breakdown First step in digestion |
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Rugae |
Folds in stomach to increase surface area and allow for more digestion |
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Pyloric sphincter |
Controls movement of food out of the stomach |
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Parts of the intestine |
1. duodenum 2. spiral valve |
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Duodenum of intestine |
Receives bile from gall bladder and pancreatic juices Continues digestion Begins absorption |
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Spiral valve of intestine |
Increase surface area Number of folds reflects diet Continues digestion Where most absorption occurs Short in sharks comparatively |
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Colon |
Intestine tapers into this muscular tube |
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Rectum |
Stores waste |
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Cloaca |
Releases waste from body |
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Liver |
Accessory digestive organ large (5-25% body weight) Produces bile, stores fat (like squalene) for energy and buoyancy Detoxifies blood and regulates blood products |
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Gall bladder |
Under medial lobe of liver Stores bile which emulsifies fat Secretes bile to duodenum through common bile duct |
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Emulsification |
Breaking up a large lipid molecule into small droplets immersed in water to prepare for lipase digestion |
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Pancreas |
Attached to duodenum Produces digestive enzymes secreted to duodenum through pancreatic duct |
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Digitiform/Rectal gland |
Finger-like structure involved in osmoregulation Removes NaCl from body and excretes it in high concentrations to the colon |
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Abdominal pores |
Lateral to cloaca Openings to pleuroperitoneal cavity |
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What is digestion rates affected by? |
1. Temperature- high temp accelerate digestion by increasing secretion of digestive enzymes 2. Amount of food- large meal digested more rapidly |
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Energy bonus |
Eat at surface in warm water then migrate to depths in cold water to slowly digest food Vertical migration |
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How does mode of life determine buoyancy? |
-large, slow sharks have large buoyant livers to make them neutral -fast sharks with smaller livers b/c swimming aids in buoyancy- dynamic lift -benthic sharks- small livers b/c swim at intervals |
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Respiration in sharks |
Gills obtain oxygen from water and excrete CO2 and waste products into water Do this via counter current exchange system |
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Gill structure |
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Secondary lamellae (lamellae) |
Site of gas exchange |
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Demibranch |
One set of filaments First and last gill Two make up one holobranch |
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Holobranch |
Two sets of filaments All except first and last |
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Gill rakers |
Filter out food |
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Counter current exchange |
Blood flow going one way, water flows in opposite direction Creates conc gradient so gases diffuse faster Low oxygen blood continuously meeting fresh water with lots of O2 |
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Ventilation |
Means by which water is passed over the gills Ram or buccal |
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Ram ventilation |
Forward movement with mouth open used to pass water over gills Highly active fish Obligate vs facultative |
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Obligate ram ventilation |
Must have forward motion at all times Can only ventilate this way |
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Facultative ram ventilation |
Use ram ventilation when moving but can actively ventilate when at low speeds or stopped |
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How does shark maintain O2 uptake when DO low? |
1. Swim faster to force more water over gills 2. Open mouth wider, seen in bonnethead 3. Change respiratory efficiency (increase blood perfusion, recruit lamellae) |
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Buccal ventilation |
Use buccal and phayngeal or gill movements to pass water over gills Some have muscles to contract gills and pump water |
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How does buccal ventilation work? |
Open mouth and close gills Depress buccal floor to create negative pressure Neg press forces water into mouth Close mouth and open gills Raise buccal floor Forces water out gills |
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Characteristics of ram ventilators |
Fast, steady swimmers Filter feeders Water passes continuously over gills Spiracles reduced or absent |
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Characteristics of buccal ventilators |
Can sit and rest on bottom Benthic sharks and rays Water pumped over gills Active spiracles Can swim slowly |
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Functions of excretion |
Maintains internal ion conc maintains body volume maintains osmotic balance removes metabolic end products removes foreign substances |
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Ureotelic |
Produce urea as nitrogenous waste product after blood filtration |
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Kidney |
Embedded in dorsal cavity wall Aids in osmoregulation Filters things out |
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Closed circulatory system |
Blood contained in arteries and veins |
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Heart |
Muscle that continually contracts to circulate blood Pumps blood Contained in pericardial cavity 2 chambered with 4 parts |
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Order of vessels |
arteries arterioles capillaries venuoles veins |
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Arteries |
carry blood away from heart typically oxygenated (except pulmonary and umbilical) |
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Veins |
carry blood to heart typically de-oxygenated (except pulmonary and umbilical) |
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Parts of blood |
1. Plasma- liquid matrix of blood (97%water) 2. erythrocytes/RBCs 3. Leukocytes/WBCs |
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Hemopoiesis |
Production of RBCs Occurs in leydig, epigonal, and spleen |
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Leydig organ |
Bilobed organ on posterior portion of esophagus May not have one if have enlarged epigonal |
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Epigonal organ |
Posterior to gonad Produces RBCs Also assists in reproduction |
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Spleen |
Large organ with red and white pulp |
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Red pulp of spleen |
Produces RBCs |
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White pulp of spleen |
Produces WBCs |
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RBCs |
Contain Hb that carries O2 Higher count in active species |
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What is RBC production influenced by? |
Temperature Higher temp yields higher production of RBCs |
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WBCs |
Part of the immune system Rids the body of foreign materials Possibly aids in blood clotting |
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Sinus venosus |
Receives deoxygenated blood |
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Atrium |
Accumulates blood Contracts and sends blood to ventricle |
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Ventricle |
Thick wall expands when atrium contracts Contracts and sends blood to conus arterious |
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Conus arteriosus |
Muscular walls and valves to absorb sudden increase in pressure Removes pusatile flow Sends blood to gills and rest of body |
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Ectothermic |
body temp regulated by env (no regulation) heat lost at gills |
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Endothermy |
Keep body temp higher than env Lamnids and thresher Whole body and regional |
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Whole body |
Entire body warmer Routes cold blood into cutaneous arteries at sides Close to veins that are warm, counter current exchange- warmth diffuses into arteries going into muscle Great white temp 14 C above env |
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Regional endothermy |
Only eye, some digestive, and brain are warmer Counter current exchange with rete mirable on smaller scale |
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Advantages of endothermy |
increased muscle power b/c warmer increased sustained swimming can invade other habitats keeps brain alert in cold water fast lactate clearance higher digestive efficiency |
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Disadvantages of endothermy |
high basal metabolic rate energetically costly must acquire more food population densities can't be as high |
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Shark osmoregulation |
Maintain 250 mmol of Na and Cl kidney reabsorbs urea and TMAO Don't need to drink water Isoosmotic to slightly hyperosmotic |
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Urea |
Nitrogenous waste product from protein metabolism Filtered out by kidney and reabsorbed toxic protein destabilizer |
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TMAO |
Molecule that can counter the destabilizing effects of urea in a 2 urea:1 TMAO ratio |
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Digitiform/Rectal gland |
Major site of salt excretion Kidneys remove excess salt and pass to gland Secretes excess salts out of cloaca as concentrated white paste |
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Bull shark osmoregulation |
Reduced urea, TMAO, and NaCl Smaller rectal gland with fewer secretory tubules |
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Nursery ground |
Where gravid females give birth and young spend first weeks |
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Gillnet |
net anchored to ground and is high |
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Aging sharks |
Take vertebrae, cut a slice, put on microscope Count number of rings Subtract 1.5 years from count |
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Order of sense that sharks rely on |
Olfaction Lateral line Auditory Vision Ampullae of Lorenzini Gestation |
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Classic olfaction work by Sheldon |
Had cloth bags with either rocks or bait inside Plugged shark nostrils and they didn't succeed in finding bait Plugged only one nostril and succeeded in finding bait |
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Largest part of shark brain |
Olfactory lobes for smell |
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What are shark nostrils most sensitive to? |
Amino acids |
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Olfactory pits |
Lined with sensitive cells Folded series of ridges lined with olfactory cells and lamellae Tiny tufts of hair project out into mucus |
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Odorant |
smell carrying substance |
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How is an odorant detected? |
Dissolves in mucus and stimulates hair cells Olfactory nerves send signal to brain |
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What do they do behaviorally to enhance smell? |
Move head from side to side to increase sense of smell and locate source (klinotaxis) Brain compare strength by each nare and turns towards strongest |
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Phases of olfaction |
1. arousal- smelling a scent 2. klinotaxis- directed approach 3. attack |
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Lateral line |
Detects changes in pressure and water displacement which are made by moving or struggling animals |
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What was the classic work by Parker in 1904 on the lateral line system? |
Sharks with no vision or hearing would still respond to a stimulus. After severance of the lateral line, shark exhibited no response to stimulus |
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Lateral line structure |
Network of fluid-filled canals that run through the length of the body and head Each canal has tiny sensory cells called neuromasts |
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Neuromast |
Has sensory hair cells- bunches of mechanoreceptors, each bunch is cupula Pressure wave moves hair and sends nerve impulse to brain |
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Classic work of Nelson and Gruber, 63 on auditory sense |
35 gray reef sharks were attracted to low frequency sounds -low frequency sounds emitted by dying fish |
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Auditory sense |
Ear in otic capsule detects sound, gravity, and acceleration 3 semicircular canals filled with endolymph for balance Shifting fluid in canals sends signals to brain |
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What are the three otoliths? |
1. utriculus 2. sacculus 3. lagena |
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Function of otolith |
Sit in center of sensory hairs Movement causes them to move and touch hairs Signal sent to brain |
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Macula neglecta |
Auditory detector in elasmobranchs Contains mechanoreceptors- group of sensory hairs embedded in cupula Send signals about pressure waves to brain |
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Classic vision work with sharks by Gilbert |
Placed covers over eyes of sharks and they were helpless |
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3 layers of shark eye |
1. sclera- 3rd layer, determine eye shape 2. chorocoid- middle layer, has tapetum lucidum 3. retina- inner layer, has rods and cones |
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Rods |
in retina detect light |
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Cones |
in retina detect color |
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Tapetum lucidum |
Series of reflecting cells containing silver guanine crystals In bright light, dark melanin granules migrate over reflective cells Light reflects back onto photoreceptors in retina |
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Ampullae of Lorenzini |
Discovered by Lorenzini in 1678 Sub-dermal canal on head and snout Pore leads to jelly filled pit with sensory nerve cells (alveoli) Detects electrical signals |
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Ampullae classic work by Dijigraaf in the 1950s |
Blindfolded catsharks turned away from rusty pole Had no response to glass rod Sharks responded to electrical currents |
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Ampullae classic work by Kalmijn |
Catshark was able to locate flounder under sand Prevent flounder from emitting electrical impulses and catshark couldn't find it |
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Internal fertilization |
All elasmobranchs Ensures the energy is passed to embryos increased efficiency of fertilization Have initial period of development that relies on yolk |
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Oviparous |
Egg laying deposit eggs in substrate Large eggs Female selects site for laying and no more care Nourished by yolk sac Females store sperm 40% sharks do this Heterodontidae, Scyliorhinidae, Orectolobidae |
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Viviparous |
Live bearing- retain embryos until fully dev Retained in uterus Aplacental and placental |
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Aplacental viviparity |
No placental connection yolk dependency, oophagous, intra-uterine cannibalism, and placental analogous |
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Yolk dependency aplacental viviparity |
Embryos depend solely on yolk Retained in uterus for protection Small at birth relating to amount of nutrients Squaliformes, Hexanchiformes, Squantiniformes, some Orectolobiformes, some Carcharhiniformes |
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Oophagy aplacental viviparity |
Lamniformes Get big Embryo depends on yolk for short time Feed on eggs Precocial teeth for rupturing eggs Largest seeks out and kills others and grows Sand tiger sharks |
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Placental analogues aplacental viviparity |
Uterine epithelium secrete a nutritive milk Produce few large young Short gestation Myliobatiformes |
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Placental Viviparity |
initially nourished by yolk sac Yolk sac connects to uterine wall forming placenta Unlimited supply of nutrients Most Carcharhiniformes |
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Testes |
Produce sperm Paired at anterior end of pleuroperitoneal cavity Enlarge during breeding |
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Epigonal organ |
Hormone facilitation and aid in production of sperm |
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Ductus deferens |
Embedded in dorsal wall transport and maturation of sperm |
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Spermatogenesis |
Production of sperm in testes Stored in epididymus and ductus deferens Held in pouches for protection from seawater |
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Ovaries |
Produce eggs and allow for accumulation of yolk to build up egg Embedded in epigonal external or internal |
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Shell gland |
Stores some sperm Site of fertilization Shell placed around fertilized egg |
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External ovary |
Compact Produce few large eggs Carcharhinids |
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Internal ovary |
Produce many small eggs Feed developing embryos Lamnids |
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Oviduct |
For egg transport Ostium is anterior portion close to ovaries |
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Ovarian cycle |
how often a female develops a batch of eggs |
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Gestation |
time between fertilization and birth |
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Annual reproductive cycles |
Give birth and mate all in one year mate right after birth Sharpnose and S. lewini |
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Biennial reproductive cycle |
Give birth one year and rest the next most Carcharhinids |
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Home range |
smallest subregion in an area that accounts for a specific portion of the space an animal utilizes |
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Approaches to assessing habitat usage |
Direct observation Relative catch rates Acoustic tracking Acoustic monitoring Satellite telemetry Archival tags Animal-borne video systems |
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Direct observation |
Simple, cheap High spatial resolution Only use in clear water during day can't detect individual behaviors observers can impact behavior |
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Relative catch rates |
Sampling gear in habitats and compare rates For population level usage Sampling gear bias |
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Acoustic tracking |
Most widely used Transmitter on each ind with distinct frequency High resolution Moderate cost Only one animal at a time Possible chasing and handling effects |
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Acoustic monitoring |
Transmitter attached to animal and ping recorded by stationary receiver Many animals at once Expensive Long term Only good if animals within range Can have simple presence/absence or triangulation |
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Satellite telemetry |
Tag transmits signal to ARGOS when shark surfaces Global coverage Long term Expensive High resolution Large animals Satellite tags use GPS Popup archival sat tags archive temp and depth and give a daily geolocation |
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Archival tags |
Determine location based on light levels, geolocation Gives depth and temperature Data stored in tags Global coverage Expensive and low resolution Must recover tag or use popup |
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Animal-borne imaging |
Habitat directly observed Expensive Low range Large sharks in clear water |
