Invertebrates

How do invertebrates and vertebrates differ?

the presence of a backbone, vertebrates have a backbone while invertebrates don’t.

Why do we call invertebrates a “term of convenience” when thinking about invertebrates and phylogeny?

because it does not represent a single, evolutionary coherent group (clade).

What kinds of symmetry exist in nature?

Reflective, Rotational, Spherical, Radial, and Bilateral

What are sponges

multicellular aquatic animals belonging to the phylum porifera, characterized by their porous bodies and lack of complex organs.

what are some key characteristics of sponges?

filter feeding, lack of organs, body structure, classification, and ecological role

What are cnidarians?

aquatic invertebrates characterized by radial symmetry, a decentralized nervous system, and specialized stinging cells called cnidocytes.

what body shape can cnidarians have

polyp and medusa

what makes cnidarians special

their radial symmetry, diploblastic body structure, cnidocytes, polymorphic life forms, and a gastrovascular cavity for digestion and circulation.

what are some examples of cnidarians

Hydras, Annella, polypodium

What are flatworms

dorsoventrally flattened acoelomates

What are roundworms?

cylindrical pseudocoelomates with a complete digestive tract

What are annelids?

segmented worms that belong to the phylum Annelida. characterized by their segmented bodies, which are divided into rings, and they possess a body cavity (coelom) and movable bristles (setae).

What are the key structures/organs of an earthworm

Mouth, Pharynx, Gizzard, Intestine.

What are mollusks

a diverse group of soft-bodied invertebrates belonging to the phylum Mollusca

What are the key structures/organs of bivalves

Mantle, siphons, gills, foot.

What are crustaceans?

a diverse group of invertebrate arthropods, mostly aquatic, with segmented bodies, jointed limbs, and a hard exoskeleton.

What are the key structures/organs of crayfish

abdomen, swimmerets, gills, green glands