3 Animal Diveristy Flashcards
What are the three major groups of deuterostomes?
Echinoderms, hemichordates, and chordates.
What are the shared derived characteristics of deuterostomes?
Radial cleavage, indeterminate cleavage, blastopore develops into anus, true coelom.
How do echinoderms change symmetry as they develop?
They have bilateral symmetry as larvae and pentaradial symmetry as adults.
What is the function of the water vascular system in echinoderms?
It is used for feeding, gas exchange, and movement.
What structure in echinoderms helps control the extension of tube feet?
The ampulla.
What are the four key characteristics of chordates?
Notochord, dorsal nerve cord, postanal tail, endostyle.
What is the function of the notochord?
It provides structural support along the body.
What evolutionary change replaced the notochord in vertebrates?
The vertebral column.
What is a cranium, and what is its function?
A skull that encases and protects the brain.
How many clusters of Hox genes do vertebrates have?
At least four clusters.
What evolutionary adaptations helped fish become active predators?
The evolution of jaws and paired fins.
What are the two main types of jawed fish?
Cartilaginous fish and bony fish.
What is the function of the swim bladder in ray-finned fish?
It helps control buoyancy.
Which type of fish was thought to be extinct but later rediscovered?
The coelacanth.
What major evolutionary step allowed vertebrates to colonize land?
The evolution of tetrapods from lobe-finned fish.
What adaptations did early amphibians need to survive on land?
Strong skeletons, lungs, skin for gas exchange, and returning to water to reproduce.
What is paedomorphosis in amphibians?
Retaining some larval traits in the adult stage.
What key adaptation allowed amniotes to reproduce entirely on land?
The amniotic egg.
What are the two groups of amniotes based on skull openings?
Diapsids (reptiles/birds) and synapsids (mammals).
What adaptations do reptiles have for life on land?
Internal fertilization, protective egg shells, dry skin, and specialized lungs and circulation.
