Quiz 8- vertebrates Flashcards
two major classes of fishes.
Chondrichthyes
Osteichthyes
Chondrichthyes
Skeletons are CARTILAGE, not BONE
Usually have ventral mouth w/ multiple rows of replaceable teeth
5-7 pairs of gill slits
Includes: sharks, skates, rays, chimera
Osteichthyes
Rigid, BONY skeleton for muscular attachent
Very diverse in body form, speed, habitat and feeding adaptations
Fixed teeth on upper & lower jaws - allow fish to chew/process their food
Jaws generally directed forward
three major reproductive methods of fishes.
oviparous
ovoviviparous
viviparous
oviparous
shed eggs directly into water column or lay them in nests in sediment/hard substrate- EXTERNALLY FERTILIZED by males
ovoviviparous
eggs are retained by the female and fertilization is internal, BUT developing embryos receive no nutrition from mother during development
viviparous
Live-bearing VIVIPAROUS fishes (relatively rare): include some sharks and bony fish species- give birth to live young- embryos develop internally + get nutrients from mother
Using proper terminology, describe the structures and processes by which fish breathe.
COUNTERCURRENT EXCHANGE
o2 taken in by diffusion
- gill arch, operculum, secondary lamella, gill filament, gill arch, lamella
Describe how different types of fishes maintain buoyancy, and explain how the swim bladder works.
swim bladder: Absorbs + secretes gasses to adjust depth at which it’s neutrally buoyant- not controlled muscularly but rather by changes in water pressure at different depths
- rete mirabile: responsible for incr. gas pressure of o2, allowing for the gas bladder to fill even in the deep sea.
- lactic acid secreted that allows hemoglobin to release o2 within the swim bladder, outside of the bladder vein still gives off o2 which diffuses back into the nearby artery going into the bladder- COUNTERCURRENT HEAT EXCHANGE
List and explain the major ways fishes use countercurrent exchange.
BREATHING
maintaining proper neutral BUOYANCY levels
-countercurrent HEAT exchange
Describe the purpose and function of major sensory systems, including the lateral line system & ampullae of lorenzini.
lateral line- canals containing a system of nerve endings along the body that detect disturbances in nearby water (water displacement)
ampullae- electroreceptors
major types of fish feeding ecology.
suction feeding
ram feeders
suction feeding
rapidly open mouth to suck in small prey + surrounding water
mouth closes rapidly
smaller prey like zooplankton are captured on gill rakers that act like a sieve
ram feeding
move forward + open jaws- engulf prey + surrounding water
water expelled thru opening gill slits
some sharks widen jaw to capture prey
2 different methods for filter feeding
- modified gill rakers strain out zooplankton from water
- some use continuous ram feeding- water constantly being strained out as the fish keeps moving thru the water