Ch 16 Fishes Flashcards
(38 cards)
Outnumber all vertebrates.
Yes 31,000 species: more than all other vertebrates combined 60% Marine
40% Fresh
What subphylum do fish belong to?
Subphylum Vertebrata (Craniata)
What fish groups have no jaws?
Class Myxini-Hagfishes Class Petromyzontida- Lampreys
What fish groups have jaws?
Class Chondrichthyes (Cartilaginous Fishes) Sharks, skates, rays, and chimaeras
What are the general characteristics of fish?
Streamlined bodies Ectothermic- derive heat from external source With endothermic exceptions Gills- extract oxygen from water Paired fins Dermal scales cover the body With notable exceptions
Hagfish:
Do they have scales?
No
Hagfish:
Fins?
single fleshy caudal fin
Hagfish:
Vertebral column?
skull but no vertebral column
Hagfish:
Jaws?
No
Hagfish:
What is unique about hagfish? (what can they do and why do they do it?)
While eating carrion or live prey, they tie their tails into knots to generate torque and increase the force of their bites.
Lampreys:
Describe these fish
A slender, eel-like body with no scales
Lampreys:
Do they have fins?
Dorsal fins, no paired appendages
Lampreys:
Jaws?
No jaws
Lampreys:
Notochord?
Notochord persists throughout life
Lampreys:
Why are they a problem?
Sea lampreys are parasitic pests. They attach to fish destroy fishery.
Lampreys:
What is their mouth like?
Disk like suction cups
Chondricthyes
What fish are in this group?
Sharks, Skates, Rays and Chimaeras
Chondricthyes
Describe body
Skeleton of cartilage Funnel-shaped body
Ventral powerful mouth Paired pectoral and pelvic fins
One or two dorsal fin Fins stiff and not very movable
Chondricthyes
Fins?
One or two dorsal fin
Chondricthyes
Jaws?
Yes
Chondricthyes
Skeleton made of?
Skeleton of cartilage
Chondricthyes
Swim bladder?
No swim bladder
Chondricthyes
What is different between shark growth in terms of scales and bony fish scale growth?
Scales reduces friction when swimming and offer protection
Chondricthyes
Where do shark teeth come from?
Teeth are modified scales
