1What ist the foot of the mollusc?
A large muscle used for movement and attachment
2Describe the mollusc head?
Well developed with sensory organs and brain
3What is inside the buccal cavity? what is its function?
Radula, a structure of tiny teeth used for scraping and collecting food.
4What is the visceral mass of the mollusc?
Containing digestive, reproductive, excretory and circulatory organs which are surrounded by hemocoel.
5What does the true coelom surround in the mollusc?
The heart and some intestines.
6What is the mantle of the mollusc?
A sheet of tissue covering the visceral mass and meeting the head and foot.
7The mantle partly encloses a space called the ____ that houses ____, where hemolymph flows inside branchial vessels.
Mantle cavity, gills.
8What does the mantle secrete?
A hard protective shell.
9Name and give function of all the layers?
Periostracum - Outermost organic (conchiolin) layer, Prismatic layer - Thick middle calcareous layer, Nacre - Inner calcareous layer
10In some taxa (clams and oysters, especially), debris between the ____ and ____ can yield ____
Nacre, Mantle, Pearls
11Describe mollusc feeding and digestion...
Complete digestive system, Many scrape food from hard surfaces. The radula lies on the odontophore.
12Describe Mollusc feeding and digestion:
Buccal cavity leads to esophagus, leads to stomach and then intestine. The anus empties wastes into the mantle cavity.
13Describe Mollusc circulation
O2 poor hemolymph flows from hemocoel to gills via afferent branchial vessels. O2 rich hemolymph from gills to atrium via efferent branchial vessels then to ventricle of heart, then leaves through aorta into the hemocoel and flows around everything.
14Describe the Mollusc excretory system:
Urine produced by the heart (atrium) fills the coelom, then enters the nephridium via the nephrostome and out via the nephridiopore.
15Describe Mollusc reproduction...
Either Gonochoristic or Hermaphroditic, Males and females shed gametes into the water column via the nephridiopore. One or more larval stages, trochophore, veliger or parasitic glochidium.
16Describe the Mollusc "brain"
Composed of mainly 2 cerebral ganglia connected by a nerve ring to each other, to several other ganglia, and to pedal and visceral nerve cords.
17Describe the Mollusc sensory system:
Chemomechanosensory tentacles, statocysts, complex eyes with ocelli, lens and cornea.