Vertebrate Classification and Characteristics

These flashcards cover key terms and concepts from the lecture notes on vertebrate classification and characteristics.

Phylum Chordata

The phylum that includes animals with a notochord, dorsal nerve cord, pharyngeal slits, and post-anal tail.

Gnathostomes

Jawed vertebrates characterized by the presence of jaws, used for grasping and slicing food.

Agnatha

Jawless fishes, such as lampreys and hagfish.

Sarcopterygii

Class of lobe-finned fishes, which are the ancestors of tetrapods.

Chondrichthyes

Class of cartilaginous fishes, including sharks and rays.

Actinopterygii

Class of ray-finned fishes characterized by bony rays in their fins.

Tetrapods

Vertebrates that possess four muscular limbs adapted for life on land.

Amniotes

Tetrapods that lay eggs with extraembryonic membranes, allowing reproduction on dry land.

Metamorphosis

Biological process by which some animals undergo significant physical changes from juvenile to adult form.

Caecilians

Legless, burrowing amphibians belonging to the order Gymnophiona.

Lissamphibia

Class that includes modern amphibians: frogs, salamanders, and caecilians.

Paedomorphosis

Retention of juvenile traits in the adult stage of an organism, seen in some amphibians.

Placodermi

Extinct class of armored jawed fishes that existed around 440 million years ago.

Diapsida

A clade of reptiles characterized by having two temporal fenestrae.

Synapsida

A clade of amniotes distinguished by a single temporal fenestra, including mammals.

Amniotic Egg

An egg that provides a protective environment and nutrients for the embryo, allowing for reproduction on land.

Oviparous

Organisms that reproduce by laying eggs.

Viviparous

Organisms that give birth to live young, rather than laying eggs.

Ectotherms

Organisms that depend on external environmental heat sources for body temperature regulation.

Lateral line system

A sensory system found in aquatic vertebrates, used to detect movement and vibrations in the water.