Ch. 33 Invertebrates

Question 1

Key characteristics of the inter vertebrates cnidarians

Answer 1

Eumetazoans phylum
- true tissues
- radial symmetry with a single opening.

Question 2

Cnidarians two major clades:

Answer 2

Medusozoans: polyp and medusa
ex: jellyfish & sea wasps

Anthozoans: poly only
ex: sea anemones & star corals

Question 3

what are the 6 diverse Lophtrochozoans groups

Answer 3

1. Flatworms
2. Rotifers & Acanthocephalans
3. Ectoprocts
4. Brachiopods
5. Molluscs
6. Annelids

Question 4

Why are lophtrochozoans grouped together?

Answer 4

due to DNA similarities

Question 5

Ecdysozoans characteristics:

Answer 5

• cuticle (external tough coat)
• cuticle sheds during ecdysis or molting

Question 6

Nematodes

Answer 6

• round bodies
• important parasite
• c elegans

Question 7

Arthropods Characteristics:

Answer 7

• segmented body
• hard exoskeleton
• jointed appendages

Question 8

Deuterostomia

Answer 8

Anus forming before the mouth.

Question 9

Echinoderms

Answer 9

-intervertebrates
- external fertilization
- slow- moving or sessile marine animals
- seas stars and sea urchins

Question 10

Rotifera we’re the first group with

Answer 10

Flow through alimentary canal

Question 11

Ectoprocts

Answer 11

Lophophore feeding and deuterostome develops

Question 12

Characteristics shared with all chordates

Answer 12

1. Notochord
2. Dorsal, hollow nerve cord
3. Bilateral symmetry
4. Pharyngeal slits
5. Muscular post anal tail