Anatomy and Adaptations of Fish
Body Plans
Function of Fish Anatomy & Fins
Body Part or Fin
Operculum
Lateral Line
Dorsal Fins
Pectoral Fins
Pelvic Fins
Anal Fin
Caudal Fin
Function
gill cover
sensory organs found in fish, used to detect movement, vibration,
and pressure gradients in the surrounding water.
increase the lateral surface of the body during swimming, and
thereby provide stability but at the expense of increasing drag.
responsible for control of directional movement, up and down or
side to side.
help balance the fish, keep it level and prevent it from rolling from
side to side.
stabilizes the fish while swimming.
moves, propels or pushes the fish through the water.
Caudal Fin Shapes and Functions
Example
Description
Rounded
Truncated
Adapted Function
Good for acceleration and
maneuvering not good for long
distance
Allows for quick turns and short
bursts of speed
Emarginate
Least amount of drag; two lobes
Forked
2 lobes; helps reduce turbulence
Lunate
Tend to be the fastest fishes;
maintains speed
Fish Body Shapes
Example
Description
Flat Body
Adapted Function
bottom dweller
Laterally
Compressed
● leisurely swimmers
● enter crevices
● for quick bursts of
speed
live in narrow spaces and
rocks
Elongate
Torpedo
fast swimmers
Mouth Shape and Functions
Example
Description
Large
Adapted Function
surrounds and
swallows prey whole
Little mouth
nibbling on small
plants/animals
Mouth Near Top
(superior)
Mouth in Middle
(terminal)
Mouth on Bottom
(inferior)
● called superior
● Eating near
surface or on
prey above
● called terminal
● Eating prey
directly ahead
● called inferior
● Eating off the
bottom