Post on 25-Feb-2016
description
Chapter 39FishesSection 3
Bony Fishes
Characteristics• Class Osteichthyes • Bone- harder & heavier than
cartridge• Lungs- early bony fishes• Swim bladder- gas-filled sac that
is used to control buoyancy • Scales- protect fish and reduce
friction when swimming
Lobe-finned fishes• Fleshy fins supported by a series of
bones• Lungfish and coelacanth• Lungfish- exchange gas through
lungs and gills (Live in tropical ponds)• Coelacanth- live deep in the ocean
Lungfish
Coelacanth
Ray-finned fishes• Do not have fins with a central
bony axis- fins supported by bony-rays
• Evolved from scales• Familiar fish- trout, goldfish, eels,
bass, guppies, salmon, perch, etc.
Trout
Perch
Goldfish
External Anatomy• Operculum- hard plate that opens at the
rear and covers and protects gills• Fins- swimming and navigation• Caudal fin- tail fin• Two dorsal fins (anterior & posterior)• Ventral anal fin- helps move in a straight line• Pelvic fins- orient body
External Anatomy• Skin- scales• Scales grow with fish• Scales overlap like shingles on
roof
Internal Anatomy• Skeleton- skull, spinal column,
pectoral girdle, pelvic girdle, and ribs• Pectoral girdle- supports pectoral fish• Digestive: Jaws, pharynx,
esophagus, stomach, intestine, liver, gallbladder, pancreas, anus
Internal Anatomy• Circulatory- gills, heart, capillaries
Respiratory and Excretory
• Countercurrent Flow- causes more oxygen to diffuse into the blood
• Urine• Urinary bladder
Swim Bladder• Sac filled with oxygen, carbon
dioxide, and nitrogen• Adjust their buoyancy based on
swim bladder
Nervous System• Brain• Optic tectum- receives and
processes information from the fish’s visual, auditory, and lateral-line systems
Reproduction• External• Lay large numbers of eggs to
ensure survival of species• Spawning- reproduction• Migrate to warm waters to spawn
REVIEW!!!• List three key features that
characterize bony fishes.• Describe the external anatomy of
fish.• Name the importance of swim
bladder.