Molluscs

Question 1

example of molluscs species

Answer 1

clams, oyster, squids, octopus, snail

Question 2

where do they live?

Answer 2

marine, fresh water, terrestrial

Question 3

are they soft or hard

Answer 3

all soft bodied some secrete a hard shell

Question 4

what are the three main parts of the molluscs

Answer 4

• muscular foot
• visceral mass
• mantle

Question 5

What is involved in the muscular foot?

Answer 5

involved in movement and senses

Question 6

what is the visceral mass?

Answer 6

digestive, aculatory, respiratory, reproductive and sensory organs

Question 7

what does the mantle do

Answer 7

excretes hard shell

Question 8

what are the three main groups?

Answer 8

• gastropods
• bivalve
• cephalopods

Question 9

give example of the species in gastropods

Answer 9

snails, limpets, whelks, conch, sea hares, periwinkles, sea slugs

Question 10

what makes gastropods different from other molluscs

Answer 10

they are the only molluscs to invade land

Question 11

what does the outer and inner layer of gastropods shells consist of

Answer 11

outer layer consists of conchiolin and inner consists of calcium carbonate

Question 12

what is the benefit of the pearl layer on the inside of the shell

Answer 12

pearl from inside shell as a defence against potentially threatening irritant such as a parasite

Question 13

what are the three classes of gastropods

Answer 13

Prosobranchia- periwinkles and limpets
Opisthobranchia- sea hares and sea slugs
Pulmonata- land and fresh water snails

Question 14

what animals belong to the bivalve group

Answer 14

mussels, clams , scallops, oysters,

Question 15

what type of feeders are bivalves

Answer 15

suspension feeders

Question 16

do bivalves have a brain

Answer 16

no

Question 17

have do bivalves open and move

Answer 17

held by a hinge ligament adductor to open
valves held by teeth in hinge

Question 18

what does cilia in the stomach of bivalves do

Answer 18

cause rotation of the contents

Question 19

what happens to waste material in bivalves

Answer 19

pushed through the rectum via anal pore

Question 20

what is the benefit of the bivalves shell

Answer 20

defence and support internal organs

Question 21

how does filter feeding work in bivalves

Answer 21

cilia on the gills capture food and they are also used for gas exchange

Question 22

what are the species that belong to the cephalopods group

Answer 22

cuttle fish, squids, octopus

Question 23

what type of feeders are cephalopods

Answer 23

predators

Question 24

do cephalopods have a brain

Answer 24

they have a brain which the cranium protects and it has separate regions that have different functions

Question 25

what are the inc sacs in cephalopods for

Answer 25

released when the animal is alarmed

Question 26

cephalopods have chromatophores for what?

Answer 26

they are present so effect of camouflage is enhanced by reflector cells