Biology of Lophotrochozoa and Cephalopods

Flashcards based on the biology and classification of Lophotrochozoa, Platyhelminthes, Annelids, and Molluscs.

Cephalopods

A class of mollusks that includes octopuses, squids, and cuttlefish, known for their advanced nervous systems and ability to experience pain.

Lophotrochozoa

A group of protostome animals characterized by either a lophophore or a trochophore larval stage.

Platyhelminthes

A phylum of flatworms which includes free-living and parasitic species, characterized by their organ-level organization.

Trematodes

Also known as flukes; a class of parasitic flatworms within the phylum Platyhelminthes.

Cestodes

Also known as tapeworms; these are parasitic flatworms with long segmented bodies, occurring in the intestines of their hosts.

Metamerism

The segmented body plan found in animals of the phylum Annelida, leading to true segmentation.

Radula

A feeding structure found in mollusks, consisting of a ribbon-like band with rows of chitinous teeth used for scraping food.

Hermaphroditic

An organism that possesses both male and female reproductive organs.

Scolices

The anterior part of a tapeworm that attaches to the intestinal wall of its host.

Bivalves

A class of mollusks characterized by having two hinged shells, including clams, oysters, and mussels.

Gastropods

A class of mollusks that includes snails and slugs, characterized by a distinct head and a single shell or no shell.

Trochophore larva

A free-swimming larval stage found in many marine animals, including some mollusks and annelids.

Closed circulatory system

A type of circulatory system where blood is contained within vessels, typically found in cephalopods and annelids.

Nervous System of Cephalopods

Highly developed compared to other invertebrates, allowing complex behaviors and pain perception.

Scolex

The head of a tapeworm, equipped with suckers or hooks for attachment to the host's intestine.