LZHS Bio II Animal Kingdom Part 2 (Higher Inverts)

Body Cavity of Mollusks & Annelids

Coelomate

(1st animals to develop a "true" coelom)

Mantle

Epidermal layer of the visceral mass of a mollusk that secretes an external shell of CaCO3 (snails, clams, octopus & squid)

Mollusk Circulatory System

Most mollusks have an OPEN circulatory system; cephalopods are the exception

Mollusk Body Symmetry

Mollusks have BILATERAL symmetry

Mollusk Digestive System

Mollusks have a COMPLETE digestive system

Phylum Mollusca has about 7 Classes: the 3 classes we studied and an example...

Gastropoda - Snails

Bivalvia - Clams & Scallops

Cephalopoda - Octopus & Squid

How organisms classified in Class Cephalopoda move...

Jet propulsion using excurrent siphons or movement using tentacles crawling on the ocean floor

Torsion

The process where the visceral mass twists during development of a gastropod

The nickname or common name of Phylum Mollusca

Soft bodied animals or Mollusks

Radula

Tongue like scraping organ; characteristic structure in mollusks (gastropods) used for eating

Trochophore Larvae

Larva of Mollusks & 1 Annelid Phylum

(Only Annelid = Polychaeta)

Gastropoda

Class of Mollusks; snails & slugs

Bivalvia

Class of Mollusks; clams; sessile filter feeders

Cephalopoda

Class of Mollusks; octopus/squid; the foot has been divided into tentacles

Oligochaeta

Class of Annelids; Earthworms

Polychaeta

Class of Annelids; Bristle Worms; marine organisms that have many setae and parapodia

Hirudinea

Class of Annelids; Leeches

Setae

External bristles used for movement in an annelid (used to classify Annelids by how many an organism has)

Parapodia

Fleshy protrusions on an annelid; used for classification (presence or absence)

The nickname or common name of Phylum Annelida

Segmented worms or Annelids

Annelid Circulatory System

Closed; contains vessels

Organ System

Organs working together to perform a specific function

Organ

Tissues working together to perform a specific function

Tissue

Cells working together to perform a specific function

Arthropoda

Phylum including insects (bees & grasshoppers), arachnids (spiders & scorpions), crustaceans (shrimp), etc.

Known for jointed appendages for specialized function in locomotion and feeding, segmentation, and a chitinous exoskeleton

Exoskeleton

The external skeleton arthropods have, made of chitin

Crustaceans

A class of Arthropods that have two pair of antennae and breathe using gills; which are inside the exoskeleton. Can range in size: a sessile barnacle to a large lobster or crab

Chilopoda

A class of Arthropods including centipedes have one pair of legs per segment and are predators

Diplopoda

A class of Arthropods including millipedes; have two pair of legs per segment and eat decaying matter

Arachnida

A class of Arthropods incuding spiders, scorpions & ticks

Metamorphosis

Complete: 2 stages of development, larva and pupa; Butterfly

Incomplete: nymph stage that molts (mini adult); Grasshopper

Insecta

A class of Arthropods with a wide range of ability to move and survive in new environments; use pheromones, sound and light to attract mates; most have 2 wings and 3 pairs of legs attached to the thorax; the MOST diverse group of animals on Earth

Comparison between Annelids and Arthropods

Segmented body patterns

Molting

The shedding of an arthropod exoskeleton in response to enzyme action, hormonal action, and pressure

Spinnerets

The small nozzle-like structures used by spiders to produce silk

Radial Symmetry

Type of symmetry echinoderms have as adults

Bilateral Symmetry

Type of symmetry echinoderms have as larvae

Water Vascular System

Type of system unique to echinoderms (the water vascular system is a system of interconnected canals and tube feet)

Endoskeleton

Type of skeleton echinoderms have; made of ossicles

Skin Gills

Some echinoderms use these to respire and remove waste

Regeneration

Process where a piece of a starfish (along with a portion of the central region) can grow a new body

Ossicles

The name of the individual plates of an echinoderms skeleton

Examples of Echinoderms

Starfish (sea stars), sand dollars, sea urchins, sea cucumbers, brittle stars & sea lillies

Lancelet

Subphylum Cephalochordata; mobile animal that filters food from water ast it enters its mouth (invertebrate); retain notochord, dorsal nerve cord, postanal tail & pharyngeal pouches

Tunicate

Subphylum Urochordata; sessile filter feeding animal (invertebrate); retain notochord, dorsal nerve cord, postanal tail & pharyngeal pouches. A tunicates outer layer is made out of cellulose!

Madreporite

a sievelike plate on the aboral surface of echinoderms through which water enters the water vascular system