Flashcards in Ch 33 An Introduction to Invertebrates Deck (61):
Three major groups of bilateral animals
Sponges have 1)___ ___ ___ but no 2)___ ___
1) Specialized cell types
2) True tissues
What kind of locomotion is exhibited by sponges?
None, they are sessile
What creates water currents that move through the body of the sponge?
Movement occurring in flagella-bearing collar cells
What supports the sponge body?
Tiny calcium or silicon structures
What structures in sponges function in digestion?
Cnidarians posses what kind of symmetry?
How do cnidarians feed?
By capturing food particles or prey from the water
What are the two body forms of cnidarians?
1) Polyp (sessile)
2) Medusa (free-swimming)
Many cnidarians have a life cycle that includes both 1)___ and 2)___ stages
Cnidarians can possess sense organs used in 1)___ and detection of 2)___
Held under high pressure (140 atm)
Launch a venomous spine at prey
Lophotrocozoans share traits of:
A horse-shoe shaped feeding structure
1) Circulatory system
2) Respiratory system
3) Skeletal system
5) Complete gut
What indicates that flatworms may not be a good monophyletic taxon?
No shared derived trait unites all members of this group
Groups based on 1)___ form have been shown to be 2)___
What was once the basis for major classification within the protostomes?
Reproduction of flatworms:
Usually, sexual via hermaphroditism
Monogeneans have what?
The unciliated synctial layer typical of flatworms (except Turberllaria)
Monogeneans are usually the parasites of what?
The skin and gills of fish
Flukes (all parasitic)
Flukes are usually the parasites of what?
A mollusc and vertebrate host
How many people are infected with flukes?
Symptoms of fluke parasitism:
4) Liver damage
Dicroceolium (Class Trematoda) alters ant behavior for what purpose?
To increase the likelihood that it will be passed on to the next host (cow)
2) Digestive system
3) Sense organs
Tapeworms are mostly the parasites of what?
The intestine of vertebrates
Comprises the body of tapeworms
Are tapeworms hermaphroditic or gonochoric?
What attaches a tapeworm to the host's intestine?
Maximum size of rotifers
What kind of habitats to rotifers live in?
A wide range of aquatic and marine habitats
Are rotifers able to survive extreme environmental conditions (drying, cold)?
Three feeding types of rotifers:
3) Filter feeders
What is the mouth of rotifers equipped with?
A hard, muscular jaw
Are rotifers hermaphroditic or gonochoristic?
Mollusca is one of the largest phylums, with over ___ species
What limits mollusk habitat?
Their need for water
What kind of climates do mollusks live in?
They are found in polar to tropical regions
What is the size range of mollusks?
Microscopic to ~1 ton
Mollusk shells are composed of ___ ___
A scraping, tongue-like feeding structure
In what mollusks is the radula found?
All major mollusk classes, except bivalves
Encloses a mantle cavity and a muscular foot
Most gastropods mollusks are ___
How do bivalves move?
1) By extending and anchoring the foot
2) Propelling water between the valves
Octopods and squid
Snails and slugs