Phylum Mollusca Flashcards
Translate Mollusca
“Soft-Bodies”
How many species?
90,000
How many classes discussed? How many in total?
4 discussed; 8 in total
List and describe each characteristics.
1) triploblastic - 3 germ layers
2) bilateral symmetry
3) cephalization - idea of head end
4) eucoelomate - has true coelom (meaning having a fluid filled body cavity surrounding the gut)
5) food - very big food group
Label parts of the organism on page 42 & also on slide 3.
Refer to said page & slide.
All organ systems with 3 germ layers have what?
Complete digestion (mouth to anus)
List some characteristics of all organ systems referring to their circulatory system.
1) Most have open with pumping heart
- heart has 3 chambers with 2 auricles and 1 ventricle
- sinuses - spaces where body fluids drain into so that the tissues will carry them and deposit elsewhere
2)closed (cephalopods) Closed circulatory system. Ex: humans
Meaning body fluid don’t leave blood vessels.
Respiratory system?
1) aquatic - gills
2) terrestrial- lungs (pulmonate snails/slugs; oxygenation in mantle)
Excretory system?
Kidneys help cleanse blood
Protostomes?
- early embryonic development
- characteristics: spiral cleavage, schizocoelous coelomic development, blastopore develops into mouth
Types of larvae
- Trochophore (most common) has cilia
- veliger also has cilia
- glochidium with bivalves and hooks that are parasitic
What does the mantle do? What is inside the mantle?
Mantle secretes exoskeleton. Inside mantle, there a mantle cavity where the gills and lungs are. Oxygen diffuses into the blood.
Locomotion of bivalves and cephalopods.
Bivalves have muscular foot for digging.
Cephalopods (like squid)
Feeding characteristics
Radula
Filter feed
Beak
Reproduction?
Dioecious (most)
Name the 4 class discussed.
Bivalvia
Gastropoda
Polyplacophora
Cephalopoda
Chitons (many shells) belongs to?
Polyplacophora
Polyplacophora anomaly?
Home scar
What was the first mollusk on earth?
Ammonite
What class is the most advanced?
Cephalopods with closed circuit system
In cephalopods, what is used to communicate?
Chromatophore cells communication is used to camouflage and send messages.
What class has internal fertilization?
Cephalopods
What is copulation?
Form of internal fertilization. Male uses hectocoytl, left arm, that goes into female’s mantle cavity to release sperm from thespermatophoric sac.
What is the difference between octopus and squid?
Octopus - intertidal
Squid - open
Chameleons of the sea who has biggest brain to body ratio
Cuttlefish
