Topic 16 Flashcards
Gnasthostomes
- Jawed vertebrates
- 2 pairs of fins
- bigger brain –> vision
- another duplication of hox gene –> diversity
what did jaws mean for gnastostomes?
diverse feeding behaviours
where did jaws come from?
jaws came from skeletal rods in the pharyngeal slits
The other slits specialized as gills
where did jaws come from?
jaws came from skeletal rods in the pharyngeal slits
The other slits specialized as gills
placoderms are
gnathostomes(big ass fish things) (goofy)
Class Chondrichthyes
what they are and characteristics
buoyency
teeth
-cartilagenous fish
-bony teeth
-Buoyency by oil in liver do not have gas filled swim bladder
Cartilagenous exoskeleton is a
Derived condition from bony skeleton
Shark scales are structured _______ to vertebrate teeth
homogeneously
Shark reproduction is
egg case is
internal
leathery
Class osteichthytes (what is in it)
monophyletic?
polyphylectic?
paraphyletic?
bony fish (dipnoi,actinistia, actinopterygii)
paraphyletic- only includes fish
Characteristics of bony fish
-ossified endoskeleton
-flat plate like bony scales\
LATERAL LINE-detects movement n shi
lungs and swim bladders are
lung was modified into
(bony fish)
Homologous
swim bladder in most
Class Actinopterygii
describe fin
and what fertilization??
Ray finned
flexible fins
external fertilization
Class Sarcopterygii
actinistia and dipnoi
joined to the body by single bone
lobe finned fish
Dipnoi
what do they have
lungfish
have gills and lungs
buccal bump
lobe finned
