Chordates and Their Characteristics (2)

These flashcards summarize key vocabulary and concepts related to chordates, their characteristics, and the classification of vertebrates as discussed in the lecture.

Chordates

Animals that have a notochord, pharyngeal slits, a dorsal hollow nerve cord, and a post-anal tail present at some stage of their life cycle.

Notochord

A flexible, rod-shaped structure that supports the body of a chordate.

Pharyngeal slits

Openings in the pharynx that appear during embryonic development, characteristic of all chordates.

Dorsal hollow nerve cord

The nerve cord found in chordates, which is located along the back.

Post-anal tail

An extension of the body past the anal opening, used for swimming in many species.

Vertebrates

Animals with a backbone or spinal column; they also exhibit additional structures such as vertebrae.

Bone

A type of connective tissue that is hard and dense, providing structural support in vertebrates.

Cartilage

A flexible connective tissue that lacks a direct blood supply and makes up the structure of some vertebrates.

Agnatha

A class of jawless fishes that includes lampreys and hagfish, characterized by the absence of jaws.

Lampreys

A group of agnathans known for their parasitic feeding behavior on larger fish.

Chevrons

Cartilaginous structures that cover the notochord and protect the nerve cord in lampreys.

Ammocetes

Larval stage of lampreys that resembles a lancelet and lives in freshwater before maturing.

Anadromous

Referring to species that migrate from the sea to freshwater to spawn.

Pheromone

A chemical substance produced and released into the environment by an animal, affecting the behavior or physiology of others of its species.

Phylogenetic classification

A classification system based on evolutionary relationships among species, derived from a common ancestor.