Vertebrates - Part 1

Flashcards covering vocabulary, definitions, and key concepts related to vertebrates and chordates from the lecture notes.

Phylum Chordata

The biological phylum that includes all animals with notochords, including vertebrates and some invertebrate relatives.

Notochord

A flexible rod-like structure found in chordates that serves as a primary skeletal support.

Dorsal Hollow Nerve Cord

A characteristic of chordates that develops into the central nervous system (brain and spinal cord).

Pharyngeal Slits

Slits that form in the pharynx of chordates and play roles in gas exchange and are present during embryonic development.

Muscular Post-Anal Tail

A tail that extends beyond the anus, present at some stage of chordate development.

Subphylum Cephalochordata

Includes lancelets, which retain characteristics of the chordate body plan throughout their life.

Subphylum Urochordata

Includes tunicates, which possess a notochord during their larval stage but may lose it as adults.

Class Agnatha

The oldest living lineage of vertebrates, characterized by being jawless.

Chondrichthyes

A class of vertebrates that includes sharks and rays, characterized by a cartilaginous skeleton.

Actinopterygii

The class of ray-finned fishes that includes the majority of fish species.

Tetrapods

Vertebrates that have four limbs, evolved from lobe-finned fishes.

Amniotes

Tetrapods that have a terrestrially adapted egg, including reptiles, birds, and mammals.

Amniotic Egg

An egg that contains membranes that protect the embryo, characteristic of amniotes.

Ectothermic

Organisms that rely on external sources to regulate their body temperature, typical of most reptiles.

Endothermic

Organisms that can generate their own heat to maintain body temperature, such as birds.

Diapsids

Reptiles with two temporal fenestrations in their skulls.

Synapsids

Reptiles with one temporal fenestration, including mammals.

Viviparous

Describes a reproductive strategy where embryos develop within the mother's body and are nourished through a placental connection.

Oviparous

Describes a reproductive strategy where eggs hatch outside the mother's body.

Ovoviviparous

Describes a reproductive strategy where embryos develop inside eggs that remain within the mother until they hatch.