Chordates and Vertebrates

These flashcards cover key concepts about chordates and vertebrates, their characteristics, divisions, and major evolutionary traits.

What are the four characteristics all chordates possess at some point during development?

Notochord, dorsal hollow nerve cord, pharyngeal gill slits, and post-anal tail

What structure does the notochord develop into in vertebrates?

Vertebrae

What is the main focus of this chapter on Chordata?

Vertebrates

What are the two invertebrate chordates found in the subphylum Urochordata?

Tunicates and salps

What is the primary lifestyle of adult tunicates?

Immobile sessile filter-feeders

Which subphylum do lancelets belong to?

Cephalochordata

What are the major groups of fish in the subphylum Vertebrata?

Jawless fishes (Agnatha), jawed fishes (Gnathostomata), cartilaginous fishes (Chondrichthyes), bony fishes (Osteichthyes)

What defines cartilaginous fishes (Chondrichthyes)?

They have a skeleton made of cartilage.

What are the two major groups of bony fishes?

Actinopterygii (ray-finned fishes) and Sarcopterygii (lobe-finned fishes)

Which group of fish gave rise to amphibians?

Lobe-finned fishes (Sarcopterygii)

What reproductive adaptation do amphibians have?

Eggs are laid in water or jelly-like substance.

What are the major orders of amphibians?

Urodela (salamanders), Anura (frogs and toads), and Apoda (caecilians)

How do mammals provide nutrients to their young during development?

Through mammary glands that secrete milk.

What is the defining feature of eutherian mammals?

They produce a true placenta that nourishes the embryo throughout development.

What adaptations aid birds in flight?

Feathers, hollow bones, and a keel-shaped sternum for muscle attachment.

What major evolutionary trait distinguishes primates?

Grasping fingers and binocular vision.