Chapter 33: Invertebrates Flashcards
1
Q
Introduction
A
- Animals that lack backbone are called invertebrates
- account for 95% of animal species
2
Q
Sponges
A
- Belong to Phylum Porifera
- Lack true tissues, organs
- Suspension feeders
- Hermaphrodites – Male/Female
3
Q
Cnidarians
A
- Belong to Phylum Cnidaria
- Clade Eumetazoa - True tissue
- Diploblastic, radial symmetry
- Two body plan
- 1. Polyp
- 2. Medusa
4
Q
2 Major Clades of Cnidarians
A
-
1. Medusozoa
- members produce a medusa
-
2. Anthozoa
- members only occur in polyps
5
Q
Medusozoans
A
- Has 3 Groups:
- Scyphozoans - true jellyfish
- Cubazoans - box jellies
- Hydrozoans - Hydra, Obelia
6
Q
Anthozoans
A
- Include sea anemones, corals
- hard exoskeleton of calcium carbonate
7
Q
Lophotrochozoa
A
- Clade characterized by
- Lophophore
- Trochophore larva
- Has six major phyla *
8
Q
Flatworms
A
- Belong to Phylum Platyhelminthes
- Include:
- Planarians
- Trematodes - flukes
- Tapeworms
9
Q
Rotifers
A
- Belong to Phylum Rotifera
- Reproduce by parthenogenesis
- offspring from unfertilized eggs
- Some species lack males entirely
10
Q
Lophophorates
A
- Have crown of ciliated tentacles around mouth
- Used in suspension feeding
- Include phyla:
- Ectoprocta - “moss animals”
- Brachiopoda - “lamp shells”
11
Q
Molluscs
A
- Belong to Phylum Mollusca
- 2nd largest animal phlya
- Most have shell
- Body w/ 3 main parts
- Foot
- Visceral mass
- Mantle
12
Q
Molluscs cont…
A
- Include clades
- Polyplacophora - chitons
- Gastropoda
- Bivalvia
- Cephalopoda
13
Q
Chitons
A
- shell of eight dorsal plates
14
Q
Gastropods
A
- Most have singled, spiral shell
15
Q
Bivalves
A
- Shells in two halves, hinged
16
Q
Cephalopods
A
- Have well developed sense organs, brains
17
Q
Annelids
A
- Belong to Phylum Annelida
- Are segmented worms
- Groups include
- Leeches
- Earthworms
18
Q
Ecdysozoans
A
- Clade characterized by shedding of cuticle
- Process called ecdysis (molting)
- Two major phyla
- Nematoda
- Arthropoda
19
Q
Nematodes
A
- belong to Phylum Nematoda
- called roundworms; many parasitic members
20
Q
Arthropods
A
- Belong to Phylum Arthropoda
- Probably 1 billion + species
- Body characteristics
- Segmented body
- Hard exoskeleton
- Jointed appendages
21
Q
Arthropod Anatomy
A
22
Q
Arthropods cont…
A
- Three major lineages
- Chelicerates
- Myriapods
- Pancrustaceans
23
Q
Chelicerates
A
- Include spiders, scorpions, ticks, mites, horse crabs
- Named after feeding appendages (chelicerae)
- serve as pincers or fangs
- Head lacks antennae
24
Q
Arachnids (group of chelicerates)
A
- Bulk of chelicerates
- Six pair of appendages
- Spiders: construct silk webs
25
Q
Myriapods
A
- Include
- Centipedes
* carnivores
* poisonous claws
- Centipedes
- Millipedes
* feed on plant matter
- Millipedes
26
Q
Pancrustaceans
A
- Newly formed clade
- Two groups
- Crustaceans
- Hexapods - insects
27
Q
Crustaceans (pancrustaceans)
A
- Include crabs, lobsters, shrimp, barnacles
- Two pair of antennae
28
Q
Hexapods (pancrustaceans)
A
- Over 900,000 species
- Head, thorax, abdomen
- Six legged - 3 pair
- 1 or 2 pairs of wings
- Undergo metamorphosis
29
Q
Deuterostomia
A
- Shares embryological characteristics
- Though primarily grouped by DNA
- Two major groups
- Echinoderms
- Chordates
30
Q
Echinoderms
A
- Belong to Phylum Echinodermata
- Slow moving, sessile
- Display radial symmetry as adults
- Include sea stars, sea urchins
