Unit 06: Animal II: Protostomes

These flashcards cover key vocabulary and concepts from the unit on Protostomes in Animal Biology.

Protostomes

Organisms in which the blastopore develops into the mouth.

Deuterostomes

Organisms in which the blastopore develops into the anus.

Lophotrochozoans

A major group of protostomes that includes flatworms, annelids, and mollusks.

Ecdysozoans

A group of protostomes characterized by an exoskeleton that is shed through molting.

Coelomate

An organism that has a true coelom, which is a body cavity lined by mesoderm.

Acoelomate

Organisms that lack a body cavity.

Radula

A toothed, chitinous ribbon used by mollusks for feeding.

Cephalization

The concentration of sensory organs and nervous tissue at the anterior end of the body.

Exoskeleton

A hard outer structure that provides support and protection, commonly found in arthropods.

Molting

The process by which an organism sheds its exoskeleton to grow.

Trochophore larva

A free-swimming larval stage characteristic of some invertebrates.

Hermaphrodite

An organism that has both male and female reproductive organs.

Gastrovascular cavity

A central cavity in which digestion and distribution of nutrients takes place.

Open circulatory system

A type of circulatory system where blood is not always contained within blood vessels.

Jointed appendages

Limbs that are segmented and enable a range of motion, characteristic of arthropods.

Foot

A muscular structure in mollusks used for locomotion.

Mantle

A fold of tissue that covers the visceral mass of mollusks and secretes the shell.

Visceral mass

The part of a mollusk that contains the internal organs.

Nematodes

A phylum of roundworms, which are unsegmented and typically have a pseudocoelom.