Animals: Mollusca

Question 1

Phylum: Mollusks
-_________________ animals
-“mollusk” means soft in Latin
-_____ largest phylum (after ___________)

Answer 1

-soft, unsegmented
-2nd
-arthropods

Question 2

Phylum: Mollusks
4 largest classes of mollusks:
1. chiton (_______)
2. bivalves (________)
3. gastropods (_______)
4. cephalopods (________)

Answer 2

-cockroach of sea
-scallops
-snail
-octopus

Question 3

Phylum: Mollusks
1. Chiton
-________ animals
-____ flat shells that overlap like shingles
-eat ______, diatoms, barnacles, and sometimes bacteria
-scrape _______ substrate with well-developed RADULA

Answer 3

-marine
-8
-algae
-rocky

Question 4

Phylum: Mollusks
2. Bivalves
-__________ shells
-_______ feeders
-keep water ______
-ex. oysters, clams, scallops, mussels

Answer 4

-2 part hinged
-filter
-clean

Question 5

Phylum: Mollusks
3. Gastropods
-“____________”
-name comes from broad flat foot on which they crawl
-ex. snails, slugs, sea slugs, limpets
-aquatic and terrestrial

Answer 5

“stomach-foot”

Question 6

Phylum: Mollusks
4. Cephalopods
-“_________”
-arms connected to head
-________
-ex. octopuses, squids, nautiluses, cuttlefish
-contain largest known invertebrate (colossal squid, up to 14 m long)

*only chordates have vertebrates

Answer 6

-“head foot”
-marine

Question 7

Phylum: Mollusks
Shared features (synapomorphies)
1. Mantle- tissue that secretes _________ carbonate in most species
-______ shells in chitons, bivalves, snails (___________)
-in cephalopods, shell is internal or ________ (nautilus)
-Mantle cavity- exposed to environment, plays role in _____________ and __________

Answer 7

-calcium
-hard
-protection
-absent
-gas exchange
-excretion

Question 8

Phylum: Mollusks
Shared features (synapomorphies)
2. ____________- provides _____________
3. Visceral mass- contains digestive, circulatory, excretory, and ___________ organs

Answer 8

-muscular foot
-locomotion
-reproductive

Question 9

Phylum: Mollusks
Other shared features
-________ digestive tract
-___ opening digestive tract (__________)
-__________ nutrition extraction from food
-Many contain a radula
-tonguelike strap with ______ made of ______
-ex. chitons, snails, slugs scrape algae off rocks or tear apart vegetation

Answer 9

-complete
-2
-mouth to anus
-improved
-teeth
-chitin

Question 10

Phylum: Mollusks
Nervous Systems
-Snails- _______
-contain _________ cells, detect ______
-eyespots detect _______
-Octopuses nervous systems much more ________
-large brain, highly developed eyes, excellent sense of _______
-organs work together to coordinate movement
-__________ color and texture of surroundings
-problem solving abilities

Answer 10

-simple
-sensory
-odors
-light
-complex
-touch
-reproduce

Question 11

Phylum: Mollusks
Diverse Reproductive Strategies

Bivalves- ______ fertilization
-release ________ into water
-in marine mollusks- ciliated, pear shaped larva settles on seafloor, develops into adult (_____ development)

Gastropods and cephalopods - _________ fertilization
-in cephalopods and snails, hatchlings resemble adults (_______ development)

Answer 11

-external
-gametes
-indirect
-internal
-direct

Question 12

Phylum: Mollusks
Importance to Humans

Diverse effects on human life, health, environmental quality
-we eat clams, mussels, oysters, snails, squids, octopuses
-pearls from ________
-_______ of bivalves
-bivalves can become __________ (if they accumulate pollutants, toxins)

Answer 12

-oysters
-shells
-poisonous

Question 13

Phylum: Mollusks
Importance to Humans
-on land, snails are ______ pests
-in water, some _____ parasitic worms (ex. flukes in snails)
-venom of cone snail can ___________
-invasive ______ mussels disrupted aquatic ecosystems in central US

Answer 13

-garden
-host
-kill humans
-zebra

Question 14

Exciting Animals

Cuttlefish
-class: ____________
-well known for “_______” colors
-displayed during fighting, catching prey, evading predators, mating
-________ of camouflage
-can also ____________

Importance to humans:
-source of _____, _______
-cuttlebone- used as a dietary supplement providing _______ for pets

Answer 14

-cephalopod
-flashing
-master
-eject ink
-ink, food
-calcium

Question 15

Absurd (but COOL) animals
Parasitic worm found in snail eyes
-worm is called Leucochloridium
-found in phylum: ________________
-invade eye stalks of snails
-mind controls host
-pulsates to __________ caterpillars
-__________ mimicry- lure prey or get itself eaten
-bird plucks snails eyes out
-worm breeds in bird’s guts
-release eggs in bird’s feces
-feces get eaten by snails

Answer 15

-platyhelminthes
-imitate
-aggressive