Phylum Annelida (segmented worms). - ppt download

Description

Main Characteristics segments true coelom (body cavity)
Phylum Annelida (segmented worms).
Main Characteristics segments true coelom (body cavity)
This is a scale worm (Polychaetes). They live 1000 meters below the water’s surface and can turn their mouths inside out.
- body segments separated by septum. ** Septum = internal wall.
-have closed circulatory system. -have well-developed nervous system (brain)
- some are hermaphrodites.
-Few setae. -Live in soil or fresh water. -Castings - enrich soil, (worm poop)
Leeches being bred for medical uses.
Marine worms. -includes: sandworms, bloodworms, fireworms. -have paddle-like appendages with setae.
Class Polychaeta (marine worms) *All are segmented, and have a coelom.
Mollusks. Kingdom Animalia, Phylum Mollusca (means soft )
Ex: snails, slugs, clams, squids, and octopi. Trochophore larva.
Foot – takes on many forms. Shell – (present in most)
Three major classes of mollusks. Gastropods. Bivalves. Cephalopods.
Move by a muscular foot. Some are poisonous, bright colors.
Check out the nudibranch gallery at nationalgeographic.
soft-bodied , head is attached to foot. foot is divided into tentacles with sucking disks. small internal shells or no shell at all.
Cuttlefish (the chameleon of the sea)
Squid have a modified shell called a pen. Well developed eyes. most complex of the mollusks.
Octopus (creeps on tentacles)
Octopus versus Shark v=p9A-oxUMAy8
Squid vs. OctopusBoth squid and octopus are aquatic animals with eight long arms. In addition to their eight arms, squid also have two long tentacles. They also have two fins on their head, unlike the octopus. Whereas an octopus has no hard shell or bone in its body, squid have a stiff backbone-like structure called a pen. A squid is any of a variety of cephalopod with a long, soft, thin body and 10 arms (eight shorter arms and two long tentacles) and two fins on its head. Squid vary in size from very small to over 65 feet in length. They prey upon fish and crustaceans. Some squid have the ability to emit an inky cloud as a defense mechanism. Their tentacles may have hooks, suckers, or sucker rings. They live in the open ocean. An octopus is any of a variety of cephalopod with a round head, soft body and 8 strong tentacles, each with two rows of suckers. Octopi range from 1 cm to over 5 meters in length. They live on the sea floor and obtain food by piercing it and injecting it with venom. v=SXgKb8GUjoM.