Chordates and Vertebrates Overview

These flashcards cover key vocabulary and concepts related to chordates and vertebrates as presented in the lecture notes.

Chordate

Any animal with a notochord or spinal cord.

Notochord

A flexible rod that supports the body of a chordate, which may develop into the spinal cord.

Dorsal hollow nerve cord

A tube-like structure that develops into the brain and spinal cord in chordates.

Gnathostome

An animal with jaws.

Amniote

An animal that reproduces with an amniotic egg.

Cephalochordata

A subphylum of chordates known as lancelets, characterized by no cranium or true heart.

Urochordata

A subphylum of chordates known as tunicates, having a notochord only in their larval stage.

Agnatha

Jawless fish such as hagfish and lampreys.

Chondrichthyes

A class of fish with cartilage skeletons, such as sharks and rays.

Actinopterygii

A class of fish with bony skeletons and ray fins.

Sarcopterygii

A class of fish with lobe fins, which are linked to amphibians.

Amphibia

A class of animals characterized by moist skin and metamorphosis.

Reptilia

A class of animals known for their amniotic eggs and scales.

Aves

A class of endothermic animals known as birds, characterized by feathers.

Mammalia

A class of animals characterized by hair, mammary glands, and parental care.

Monotremes

Egg-laying mammals such as the platypus and echidna.

Marsupials

Pouch mammals such as kangaroos and koalas.

Placental mammals

Mammals that give birth to live young and have a placenta.

Heart evolution

The trend of increasing heart chambers correlating with improved oxygen efficiency.

Thermoregulation trend

The evolution from ectothermic to endothermic organisms.

Reproduction trend

The shift from water eggs to amniotic eggs and eventually to live birth.

Respiration trend

The evolution from gills to skin + lungs to lungs only.

Habitat trend

The transition from aquatic to land, and then to air habitats.

Body covering trend

The evolution of body coverings from scales to moist skin to feathers to fur.