Echinodermata, Chordata, and Fish Anatomy Flashcards

Flashcards about Echinodermata, Chordata, and Fish Anatomy

Endoskeleton (Echinodermata)

Internal support system made of calcium plates (ossicles) that grows with the animal, maintains body shape, and often has spines for protection.

Radial Symmetry (Echinodermata)

Most have five-part symmetry as adults.

Water Vascular System (Echinodermata)

Replaces blood; uses seawater to move, feed, and breathe.

Digestive System (Sea Star)

Includes mouth, stomach, and pyloric caeca; stomach can evert to digest prey externally.

Reproductive Organs (Sea Star)

Each arm contains gonads; capable of sexual and asexual reproduction.

Nervous System (Sea Star)

Nerve ring and radial nerves in each arm; no centralized brain.

Water Vascular System (Sea Star)

Made of madreporite, stone canal, ring canal, radial canals, ampullae, and tube feet; functions in locomotion and feeding.

Aboral Surface

Top side of a sea star; contains anus, madreporite, and spines.

Oral Surface

Underside of a sea star; contains mouth and tube feet (in ambulacral grooves).

Water Vascular System Function (Sea Star)

Movement via tube feet, gas exchange, and feeding.

Sexual Reproduction Advantage

Increases genetic diversity.

Asexual Reproduction Advantage

Allows regeneration; survival if damaged or when mates are scarce.

Asteroidea Characteristics

More than 5 arms, feed on bivalves

Ophiuroidea Characteristics

Long, slender arms; tube feet without suction

Echinoidea Characteristics

Spherical/disc-shaped; no arms; covered in moveable spines

Holothuroidea Characteristics

Five rows of tube feet, soft body, regenerate digestive organs

Chordata Common Characteristics

Dorsal nerve cord, pharyngeal slits or gill pouches, post-anal tail

Ectothermic Definition

Body temp depends on environment

Endothermic Definition

Maintains constant body temp internally

Feathery Structure (Gills)

Increases surface area for oxygen absorption in fish gills.

Agnatha Characteristics

Jawless, no paired fins, cartilage skeleton

Chondrichthyes Characteristics

Cartilage skeleton, jaws, paired fins

Osteichthyes Characteristics

Bony skeleton, swim bladder, operculum