Fishes Flashcards
How long ago did fishes first appear?
500 million years ago
List 5 characteristics that the Subphylum Vertebrata makes them different from other Chordates?
- Vertebral Column/backbone
- Spinal Chord
- Skull
- Bilateral Symmetry
- Usually 2 pair of appendages
Fishes are in what Phylum?
Chordata
Vertebrates include which animals?
- Fishes
- Amphibians
- reptiles
- Birds
- Mammals
What is the scientific study of fishes called?
Ichthyology
Why are fish important?
- Ecosystem
- Food
- Economy
- Recreation
How many species are in the Vertebrates?
40,000
The Class Agnatha is under which subphylum?
Vertebrata
Jawless Fishes are in what Class?
Agnatha
What do jawless fishes lack compared to other fishes?
- Jaws
- Paired fins
- scales
What fishes are under the class Agnatha?
- Lampreys
- Hagfish
Where do Lampreys live?
Young lampreys live in freshwater. Adults live in the ocean
How do Lampreys feed?
They use their mouth as a suction cup on larger fish
Where do Hagfish live?
The ocean.
Hagfish, How do they feed and what do they feed on?
They are scavengers that feed on dead animals that fall to the sea floor
What do Hagfish use for defense?
Slime on their body
Hagfish skin is sometimes used for what?
Leather products
In the Class Chondrichthyes what kind of fish are in this group?
Sharks and Rays
What is the skeleton made of in the Chondrichthyes?
Cartilage
How is Cartilage different from bone?
Cartilage is soft, elastic and flexible. Bone is tough, inelastic and inflexible.
What is the benefit of having paired fins?
- Steering
- Stability
In Sharks, what does it mean to be fusiform?
pointy at the end, round in the middle
In Sharks, what does it mean to be countershaded?
Dark on the dorsal surface and light on the ventral surface
How many gills slits do sharks usually have?
5-7
What is a spiracle and what is it’s function?
To take in water and ventilate the gills
In a shark which fins are paired?
The pectoral and pelvic fins
What is the function of the pectoral fin?
For steering and lift
What is the function of the pelvic fins?
For stability
What is the function of the caudal fin?
propulsion through the water
Explain what it means for a caudal fin to be heterocercal?
The upper lobe is longer than the lower lobe
Why do some shark species need to keep swimming?
because their gills only work when water is flowing across their membranes
What will happen if shark stop swimming?
they die
How can some species of shark rest on the sea floor?
They have the ability to open and close their mouth to pump water and force it across their gills
What happens when a shark loses a tooth?
it is replaced