COMMON CHARACTERISTICS

• No tissues or organs
• Body consists of a hollow tube with pores in its wall
• Feed by pumping in water, along with bacteria, algae, and small particles of organic material, through their pores
• Free-swimming larvae
• Sessile as adults

COMMON CHARACTERISTICS

• Radially symmetrical
• Tentacles armed with rows of stinging cells, used to paralyze prey

COMMON CHARACTERISTICS

• Most have a shell that protects the soft body
• Mantle (tissue that forms the shell)
• Radula (sandpaper-like tongue structure used during feeding; present in all except bivalves)

COMMON CHARACTERISTICS

• Well-defined head and tail regions
• Hermaphroditic and can engage in both sexual and asexual reproduction
• Some have a single opening in the body, which serves as a mouth and an anus

COMMON CHARACTERISTICS

Possess four common body structures, although these structures often are only present during specific life stages:

• Notochord
• Dorsal hollow nerve cord
• Pharyngeal slits
• Post-anal tail

COMMON CHARACTERISTICS

• Segmented body

COMMON CHARACTERISTICS

• Segmented body with a distinct head, thorax, and abdomen
• Exoskeleton made of chitin
• Jointed appendages

COMMON CHARACTERISTICS

• Enclosed by a hard skeleton under spiny skin
• Larvae are bilaterally symmetrical and share some anatomical features with chordates
• Adults are radially symmetrical
• Undersides are covered with tube feet that aid in locomotion and grasping

COMMON CHARACTERISTICS

• Long, narrow unsegmented body
• Bilaterally symmetrical
• Surrounded by a strong, flexible cuticle
• Must molt in order to grow larger