An Introduction to Animal Diversity

Page
5

Ecdysis - Shedding of Exoskeleton

Slide 29

Some lophotrochozoans have a feeding structure called a lophophore.

Other phyla go through a distinct developmental stage called the trochophore larva.

Slide 30

Lophotrochozoans Characteristics

Lophophore

Apical tuft

of cilia

Mouth

(a) An ectoproct

(b) Structure of a trochophore

larva

100 µm

Anus

Slide 31

Animal Phylogeny

Common ancestor

of all animals

True

tissues

Sponges

(basal animals)

Ctenophora

Cnidaria

Acoela (basal

bilaterians)

Deuterostomia

Lophotrochozoa

Ecdysozoa

Metazoa

Eumetazoa

Bilateria (most animals)

Bilateral

summetry

Three germ

layers

Slide 32

You should now be able to:

List the characteristics that combine to define animals.

Summarize key events of the Paleozoic, Mesozoic, and Cenozoic eras.

Distinguish between the following pairs or sets of terms: radial and bilateral symmetry; diploblastic and triploblastic; spiral and radial cleavage; determinate and indeterminate cleavage; acoelomate, pseudocoelomate, and coelomate

Compare the developmental differences between protostomes and deuterostomes.