Invertebrates: Phylum Mollusca- Class Bivalvia- (EXAM 2)

Question 1

Class Bivalvia

Answer 1

• under phylum Mollusca
• ex) mussels, clams, scallops, oysters
• 1-2 mm to 1 m in length (500lbs)

Question 2

feedings

Answer 2

siphon or filter feeding by ciliary movement of gills that draws food material into the shell

Question 3

laterally compressed

Answer 3

with two shells (bivalve: both are symmetrical) held together by a hinge ligament; shells closed by adductor muscles (use as a defense)

Question 4

Chemoreceptors

Answer 4

poorly developed sensory organs

Question 5

locomotion

Answer 5

muscular foot extends between the halves

Question 6

location

Answer 6

• many bivalves burrow into the mud or sand (clams)
• some bore into rock and wood
• byssal threads (beard): mussels attachment to substrate (sessile)

Question 7

shellfish poisoning

Answer 7

biotoxins: ingestion of numerous dinoflagellates

Question 8

commercial value for human consumption

Answer 8

oysters, scallops, clams, mussels (aquaculture)

Question 9

nacre or mother-of-pearl

Answer 9

secreted by epithelial cells in the mantle

Question 10

pearl production (in oysters)

Answer 10

is the by-product of a protective device used by the animal when a foreign object becomes lodged between the shell and mantle (layers of nacres around object to produce a blister pearl attached to the interior of the shell or a free pearl w/in the mantle tissues)

Question 11

Decorative use

Answer 11

widely used for pearl buttons during the 1900s as inlay on guitars and valve buttons on trumpets, used so to make spoon like utensils for caviar so as to not spoil the taste with metallic spoons; other uses include carved and inlay for alter-pieces, carved nacre pieces and gunpowder flakes