Biology 100 Unit 19 Flashcards
Biologists have developed hypotheses for the evolution of chordate groups using
anatomical
molecular evidence
fossil evidence
Hagfishes and lampreys.
– have a notochord, but
– lack hinged jaws and paired fins.
– These are fish used to establish a lineage of other fish with heads
quickly diversified using their paired fins and tail to chase a wide variety of prey.
Jawed vertebrates:
Jaws may have evolved by modifications of skeletal supports of the _____________________________.
anterior pharyngeal (gill) slits
The remaining gill slits remained as sites of _______
______________.
gas exchange
What are the 3 lineages of jawed fishes with gills
- chondrichthyan
- ray-fined fishes
- lobe-finned fishes
examples of chondrichthyans
sharks and rays
examples of ray-finned fishes
tuna, trout, and goldfish
examples of lobe-finned fishes
coelacanths and lungfish
Jawed vertebrates with gills and paired fins include
sharks, ray-finned fishes, and lobe-finned fishes
sharks and rays are an example of
Chondrichthyans
Chondrichthyans have a flexible skeleton made of _______,
cartilage
Chondrichthyans have a ______________________ which contains sensory organs helping these organisms sense a change is temperature or water pressure.
lateral line system
Chondrichthyans have ________________ on their heads,
electrosensors
trout, tuna, goldfish, etc. are examples of
Ray-finned fishes
Ray-finned fishes have an internal skeleton reinforced with a hard matrix of
___________________, flattened scales covered with mucus,
calcium phosphate
Ray-finned fishes have an ______________ that covers a chamber of gills, and a a buoyant ____________
operculum, swim bladder
_________________ with gills and paired fins include sharks, ray-finned fishes, and lobe-finned fishes
Jawed vertebrates
Lobe-finnedfish: ____________________________ __________ that are supported by rod-shaped bones.
have muscular pelvice and pectoral fins
living deep in the oceans, were once
thought to be extinct,
coelacanths
which can gulp air into lungs, inhabit stagnant waters in the Southern Hemisphere, and
lungfishes
, adapted to life on land, include terrestrial vertebrates.
tetrapods
Tetrapods are _________________________________ ______________________________.
jawed vertibates with limbs and feet that can support wight on land
Tetrapods are considered to have evolved from a lineage of
lobe-finned fish.
_____________________________ in vertebrate history, and all subsequent groups are considered descendants of these early land-dwellers.
Adapting to life on land was a key event
Like plants, vertebrates faced _____________________
obsticles on land – gas exchange, – water conservation, – structuralsupport, – a means of locomotion, – adapting sensory organs that worked well in water but not on land, and – reproduction.
Amphibians are____________________—vertebrates with two pairs of limbs
tetrapods
salamanders, frogs, and caecilians,
Amphibians
Amphibians
– use their moist skins to supplement their lungs for gas
exchange,
– often have poison glands in their skins,
– usually return to standing water to reproduce,
– undergo metamorphosis from a larval stage to the adult
–Were the first tetrapod to move on land
–Were the first tetrapod to move on land
Amphibians
are amniotes—tetrapods with a terrestrially adapted egg
reptiles
Reptiles (including birds) and mammals are ____________
.amniotes