Biology 202 - Lab 2

  1. Dog fish integument:
    identify: epidermis, dermis, scale, mucouse gland, and a chromatophore (pigment containing and light reflecting cells)
  2. Types of fish scales:
    • Placoid scales (cartilagenous fish): tooth like structure containing a pulp cavity srrounded by dentine and capped by enamel (much like shark teeth and may have evoled from them)
    • Ganoid scales(non teleost bony fishes): lower bony layer topped by enamel like material termed ganoine. thin scales interlock to form tough armour
    • Cycloid and ctenoid scales (teleost bony fishes): thin layer of bone (no enamel, dentine or ganoine), so are light and flexible. allow for mobility and speed
  3. Support and locomotion:
    • Varies tremendously
    • Tuna have fusiform shape and are among the fastest swimmers
    • Lumpsuckers have globiform shape and are poor swimming bottom dwellers
    • fintypes and shape (size of caudal fin used for propolsion) also give some information
  4. Food Aquisition and Digestion
    • Development of jaws are verry important to evolution
    • gives more options for what is can eat - and how it captures and manipulates food
    • jaws thought to have evolved from gill arches (seen in Chondrocythhes such as dog fish)
    • Chondrocythe jaw problem - gap in corner of mouth for escape
  5. Gas Exchange and Water Balance: Respiration
    • main processes: anaerobic glycolysis, and aerobic respiration
    • evolved respiratory features: gills, lungs, cutaneous respiration
    • Gills are delicate filamentous structures that are heavily vascularized (may be visible or hidden by gill covers)
    • occur in primarily the cephalic region
    • maximize seurface area for respiration
    • sharks: gills are on interbranchial septa (septal gills) and tips of interbranchial septa acts as valves that can close external gill slits
    • bony fish: gills covered by an operculum.
    • large common opercal cavity for all gills
    • inter branchial septa reduced so that primary gill lamellae extend freely into opercular caity (these are aseptal)
  6. Gas Exchange and Water Balance: Circulation
    • heart: resposible for pumping blood through the system
    • under autonomic control
    • adjusts to match metabolic needs
    • Fish: blood only passes through heart 1 time so only need 1 atrium and ventricle (also have sinus venosus, and bulbus arteriosus but are non contractible)
    • considered either 2 or 4 chambered
    • blood in capillary beds loses pressure. not a problem for fish as blood doesnt need to overcome large gravitational forces and they dont have large metabolic needs
  7. Gas Exchange and Water Balance: Excrition
    • Fresh water Teleosts (perch): hyper osmotic (water in solutes out) excrete highly gilute urine and limit water intake
    • Opisthonephric Kidney: eliminates excess water
    • ammonia secreted through gills as special glands in gills absorb salt
    • Marine teleosts: hypo osmotic (water out solutes in) drink water and excrete concentrated urine
    • Sharks: convert ammonia to urea and retain it in their blood making them iso osmotic (high tolerance to urea). excrete excess salts via special rectal gland
  8. Sensory Abilities: Nervous system
    • 3 components: central, peripheral, autonomic nervous systems
    • parts of brain that are used more are larger and mor complex
    • Bottom feeding fish: rely on smell to find food thus have large olfactory lobes and telencephalon
    • Surface feeding fish: rely on sight to find food thus have large optic lobes and small olfactory apparatus
  9. Sensory Abilities: Sensory reception
    • 4 sensor modalities: chemo, mechano, photo, and thermoreceptors
    • Chemoreception: most primitive and in all animals
    • salmon: can go from open sea to hatch site based off of dilute chemical trail
    • Bony fish: have lateral lines (sense organ dectecting movement in fluid) seen running down the sid
    • Sharks: some have modified lateral organ with electro receptors that can sense magnetic feilds
  10. Reproduction:
    • Viviparous: (sharks, dogfish) embryos develope in female. needs a uterus
    • Oviparous: (perch, most fish) embryo developes inside an egg. eggs laid and strewn across weeds
    • Oviviparity: eggs retained in mother during development
    • these a a reflection of environmental stresses affecting offspring survival
    • External Fertilization: fertilization in external environment. pheremones used to attract mates. eggs laid in strategic locations (temperature predation water quality)
    • Internal Fertilization: fertilization in female reproductive tract. these individuals developed elaborate neural and pheremonal mechanisms for facilitating copulations.
  11. propose an adaptive advantage of the heavily ossified skull
  12. perch are carniverous fish. how might hinged jaws aid in prey capture?
  13. Based on the size and shape of the teeth do you think the fish chews its prey or swallows it whole?
  14. how is the shape of the perch well adapted to minimize drag during swimming?
  15. which fins are involved with steering and which are involved with in propulsion? which fins would be used to slow the fish after a quick burst of speed? do any of the fins appear to have no obvious function?
  16. is your specimine male or female?
  17. what kind of scales do perch have?
  18. how are the gills of perch well suited to facilitate gas exchange?
  19. propose a function for the gill rakers
  20. how is the shark well adapted to minimize drag during swimming?
  21. which fins are involved with steering and which are involved in propolsion?
  22. what is the most likely function of the spiral valve in the intestine?
  23. is your specimen male or female?
  24. why are opercula considered and evolutionary advancement in the bony fish?
  25. the caudal fins of perch and dogfish sharks differ in shape. what effect might theis have on their swimming?
  26. what advantage do fish with swim bladders have?
  27. what features do you think might favor internal vs external fertilizations?
  28. how do the reproductive systems of the dog fish and perch differ? how does this relate to their mode of reproduction?
  29. which regions of the brain are relativley more and less developed? what does this say about abilities of perch and shark?(seeing smelling maneuvering orienting and reasoning)?
  30. Skeletal system of a bony fish:
    • dermal exoskeleton and a bony endoskeleton
    • hinged jaws
    • teeth
  31. External Anatomy of a Bony Fish:
    • nostrils:
    • eyes:
    • mouth
    • opercula:
    • dorsal, pelvic, pectoral, 2nd dorsal fin, anal, caudal fins:
    • anus:
    • urogenital opening:
    • scale:
    • lateral line:
  32. Internal Anatomy of a Bony Fish:
    • Gills:
    • Gill Filaments:
    • gill rakers:
    • liver:
    • kidney:
    • urniary bladder
    • swim bladder
    • pyloric ceca:
    • spleen:
    • stomach:
    • intestines:
    • gonads:
    • heart:
    • pericardial cavity:
    • brain:
  33. Chondrichythe Anatomy:
Card Set
Biology 202 - Lab 2