Lab 12: Vertebrate Homologies

Flashcards derived from lecture notes on vertebrate homologies, focusing on taxonomy, anatomy, and evolutionary biology concepts.

Deuterostomes

A group of animals that includes vertebrates, characterized by bilateral symmetry and a specific embryonic development.

Phylogeny

The evolutionary history and relationship among species.

Teleost fish

Modern bony fishes that exhibit advanced features such as improved gas exchange and efficient locomotion.

Skeletal homologies

Similar bone structures among different vertebrate species that indicate a common ancestry.

Radial symmetry

A body plan in which parts are arranged around a central axis, as seen in some adults of Echinoderms.

Echinoderms

Marine animals with radial symmetry, such as starfish and sea urchins.

Hemichordates

A marine phylum that shares some characteristics with chordates, including the presence of pharyngeal slits.

Chordata

A phylum that includes all vertebrates and some invertebrate groups, characterized by the presence of a notochord.

Notochord

A flexible rod that provides support and develops into the spine in vertebrates.

Dorsal hollow nerve cord

A structure that develops into the spinal cord in vertebrates.

Post-anal tail

A tail that extends beyond the anus and is present in some chordates.

Pharyngeal slits

Slits in the embryonic pharynx that develop into various structures such as jaws and ears in vertebrates.

Agnatha

A class of jawless fishes, including lampreys and hagfish.

Osteichthyes

A class of bony fishes, which includes both ray-finned and lobe-finned fishes.

Chondrichthyes

A class of cartilaginous fishes including sharks and rays.

Amphibia

A class that includes amphibians such as frogs and salamanders.

Amniotes

Group of vertebrates that produce eggs with an amnion, including reptiles, birds, and mammals.

Gnathosomes

Jawed vertebrates, characterized by the presence of jaws.

Cartilaginous fishes

Fishes whose skeletons are made of cartilage instead of bone.

Swim bladder

An internal gas-filled organ that helps bony fish regulate buoyancy and maintain depth.

Counter-current exchange mechanism

A system in the gills of fish that maximizes oxygen extraction from water.

Lateral line system

A sensory organ in fish that allows them to detect vibrations and movement in the water.

Taxonomy

The science of classifying organisms.

Homology

A similarity in structures due to shared ancestry.

Analogous structures

Structures that serve similar functions but do not share a common ancestor.

Convergent evolution

The process where unrelated species evolve similar traits due to similar environments.

Homodont

A term for teeth that are uniform in size and shape.

Heterodont

A term for teeth that differ in size and shape.

Incisors

Teeth located at the front of the mouth used for cutting and scraping.

Canines

Teeth located next to incisors, often used for stabbing and holding prey.

Premolars

Teeth located behind canines used for grinding food.

Molars

Teeth located at the back of the mouth, primarily used for grinding.

Hypsodont

High-crowned teeth that extend far above the gum line.

Brachydont

Low-crowned teeth found in species like humans.