Download File

Common Group
Name: Fishes
Phylum: Chordata
Examples:
• Jawless Fishes
•Sharks and Relatives
(Cartilage Fishes)
•Bony Fishes
Body Plan
 Vertebrate
 Bilateral
Symmetry
 Paired fins
 Scales
 Gills
 Jaws
Feeding
• All types of feeding in fishes: H, C,
D, FF, P
• Path of Digestion:
Mouth- esophagus- stomachpyloric ceca (enzymes for digestion)intestine- anus
Respiration
 Most fishes exchange gases
using gills.
 Water is pulled in through
mouth- water pumped over gill
filaments- oxygen rich water
is taken in- oxygen poor water
pumped out of slits.
Circulation
• Closed Circulatory System
• Heart pumped blood around in a single
loop
• Path of blood:
heart- gills- rest of the body- heart
• 4-part heart: sinus venosus, atrium,
ventricle, bulbus (conus)arteriousus.
*Only 2chambers
Excretion
• Some waste removed
through gills.
• Other waste is removed by
kidneys.
• Kidneys also help control
the amount of water in the
body.
Response
• Multi-part brain:
1) Olfactory Bulbs- receive smell
2) Cerebrum- processes smell
3) Optic Lobes- process info. from eyes
4) Cerebellum- coordinates body
movements
5) Medulla Oblongata- functions of
internal organs
• Highly developed sense organs for sight,
taste, smell, sound, and touch.
Movement
• Move by alternating contractions
between paired muscles.
• Fins aid in propelling and
direction
• Swim bladder is a gas-filled organ
that adjusts buoyancy.
 Internal
Reproduction
or external depending on
species.
Oviparous- fish whose eggs develop
externally. (Salmon)
Ovoviviparous- fish whose eggs
develop internally with nourishment
from the egg. (Guppies)
Viviparous- Fish whose eggs develop
internally with nourishment from
the mother’s body. (Sharks)
Other Information
• Evolution of fishes:
Earliest fishes: jawless, bony plate
armor
Next Fishes: Jawless, little body
armor, ancestors of lampreys and
hagfishes
Next Fishes: Jaws and paired fins
arrived
Modern Fishes: Two main groups that
gave rise to cartilage fish and bony
fish