Fishes Flashcards
What were the earliest vertebrates
Conodonts
Define a fish
A poikolithermic, aquatic chordate with appendages called fins whose chief respiratory organs are gills and are covered in scales
What superclass do the Myxini and Petromyzontidae make up - give 1 example for each
Agnathostomes
M - Hagfish
P - Lamprey
What superclass do the Chondrichthyes and Osteichthyes make up
Gnathostomes
What did the jaws evolve from
Gill arches
Chondrichthyes has 2 sub-classes - Elasmobranchii and Holocephali - What are the 2 sub-classes of Elasmobranchii - what do they include?
Selachii - Sharks
Batoidea - Rays
Selachii - Type of tail, name of fins for stabilisation, name of scales and buoyancy regulation
Heterocercal tail
Pectoral and pelvic
Placoid
Oil-filled liver
How do the batoids move
Undulation of pectoral fins
Define Oviparous, Ovoviviparous and Viviparous
Ovi - Egg hatches and develops outside of mothers body
Ovo - Egg develops partially inside mothers body then is laid and hatches outside mothers body
Viv - Embryo develops completely within the uterus and is born live
Name given to structure sharks have which allows them to detect magnetic fields produced by other organisms
Ampullae of Lorenzini
What is the lateral line
A row of sense organs that sense pressure
What is the skeleton of both the agnathostomes and the Chondrichthyes made of
Cartilage
What are the 3 distinguishing features of the class Osteichthyes
Bony-fish
Protective operculum
Gas-filled bladder / Swim bladder
The bony fish are split into the Actinopterygii and the Sarcopterygii - what is the main difference
A - Ray-finned fish
S - Lobe-finned fish
What are most actinopterygii also called
Teleosts
