LABORATORIO Annelida

LABORATORIO

Annelida

EJERCICIO 12

Goals for today• Learn to recognized the Phylum Annelida from

other animals• Learn the main ‘diagnostic’ characteristics• Learn about some species biology

AnnelidaAnnelids include earthworms, leeches, and marine polychaetes.

Key characteristics of the phylum:• Esquizocoelomates• Triploblastic• Bilateral symmetry• Cephalization• Protostomates• Segmentation or metamerism• Belong to phylogenetic clade:

Lophotrochozoa• Complete digestive system

Porif

era

Parazoa

Deut

eros

tom

ia

Ecdy

sozo

a

Anne

lida

Mol

lusc

a

Loph

opho

rata

Rotif

era

Plat

yhel

min

thes

Lophotrochozoa

Eumetazoa

BilateriaRadiata

Protostomia

Cnid

aria

and

Cte

noph

ora

Lophotrochozoa

Mollusks: Your TasksExercise 12A:

– Phylum: Annelida• Clase Polychaeta

• Genus: Nereis

Nereis is a sandworm strictly marine. They live in the mud and debris of shallow coastal waters often in burrows. Largely nocturnal. They reach 0.5 m

Annelida: Polychaetes1. Observe lamina de parapodia. Identify the parts in the figure.

Where is the notopodium and neuropodium?

Annelida: Polychaetes1. Observe preserved polychaetes. Put one in a petri dish and

observed the following structures in the dissecting scope

Mollusks: Your TasksExercise 12B:

– Phylum: Annelida• Clase Oligochaeta

• Genus: Lumbricus terrestris

Lumbricus terrestris prefers moist, rich soil that is not too dry or sandy. They are primarily nocturnal and come out of their borrow at night to forage

Annelida: Lumbricus1. Observe slide of cross section of an earthworm: look for he

following parts

Annelida: Lumbricus1. Dissection: of an earthworm and look at the external anatomy

Annelida: Lumbricus

1. Dissection: of an earthworm and look at the internal anatomy

What are the crop and gizzard for?

Is their circulatory system open or close?

Annelida: Lumbricus

Dissection in a ‘fresh’ worm, noticed the location of the typhlosole

Wha is the function of the typhlosole?

Mollusks: Your TasksExercise 12C:

– Phylum: Annelida• Clase Hirundina

• Genus: Hirudo medicinalis

Medicinal leeches are any of several species of leeches, but most commonly Hirudo medicinalis, the European medicinal leech

Mollusks: HirudoMedicinal leeches are now making a comeback in microsurgery. They provide an effective means to reduce blood coagulation, to relieve venous pressure from pooling blood (venous insufficiency), and in reconstructive surgery to stimulate circulation in reattachment operations for organs with critical blood flow, such as eyelids, fingers, and ears. The therapeutic effect is not from the blood taken in the meal, but from the continued and steady bleeding from the wound left after the leech has detached.

http://www.arkive.org/medicinal-leech/hirudo-medicinalis/video-00.htmlVideo

Annelida: Hirudo1. Observe slide of a leech: identify the oral and caudal suckers,

pharynx, and crop.

Links• http://en.wikipedia.org/wiki/Hirudo_medicinalis• http://www.arkive.org/medicinal-leech/hirudo-medicinalis/