Chapter 24: Fishes, Osteichthyes, Class: Actinopterygii Flashcards
1
Q
What are these fishes called?
A
Ray finned fishes
2
Q
Teleosts?
constitute 96% of all living fishes and half of all vertebrates. List some characteristics about the habitats they exist in (4)
A
- survive in 8,000 meters below the ocean surface
- they can survive in temperatures from 44 degrees Celsius(in hot springs) to -2 degrees Celsius (under Antarctic ice)
- some live in salt concentrations that are 3 times that of seawater
- others can be found in swamps devoid of oxygen
3
Q
Fishes in this class have heavy dermal armour replaced by what type of scales?
A
- light, thin, flexible cycloid and ctenoid scales
4
Q
What organisms lost their scales?
A
- some eels and cat fishes
5
Q
What is the benefit of not having heavy armour?
A
- increased mobility helping them avoid predators and improved feeding efficiency
6
Q
List the functions of their modified fins!
A
- braking, streamlining and social communication
- Homocercal tail allowed greater spend and buoyancy
7
Q
Their jaws modified to increase what?
A
- suctioning and protrusion to secure food
8
Q
What kind of swimming can they do that sharks cannot?
A
- swim backwards
