Phylum Mollusca

Question 1

Translate Mollusca

Answer 1

“Soft-Bodies”

Question 2

How many species?

Answer 2

90,000

Question 3

How many classes discussed? How many in total?

Answer 3

4 discussed; 8 in total

Question 4

List and describe each characteristics.

Answer 4

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

Question 5

Label parts of the organism on page 42 & also on slide 3.

Answer 5

Refer to said page & slide.

Question 6

All organ systems with 3 germ layers have what?

Answer 6

Complete digestion (mouth to anus)

Question 7

List some characteristics of all organ systems referring to their circulatory system.

Answer 7

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.

Question 8

Respiratory system?

Answer 8

1) aquatic - gills

2) terrestrial- lungs (pulmonate snails/slugs; oxygenation in mantle)

Question 9

Excretory system?

Answer 9

Kidneys help cleanse blood

Question 10

Protostomes?

Answer 10

• early embryonic development

- characteristics: spiral cleavage, schizocoelous coelomic development, blastopore develops into mouth

Question 11

Types of larvae

Answer 11

• Trochophore (most common) has cilia
• veliger also has cilia
• glochidium with bivalves and hooks that are parasitic

Question 12

What does the mantle do? What is inside the mantle?

Answer 12

Mantle secretes exoskeleton. Inside mantle, there a mantle cavity where the gills and lungs are. Oxygen diffuses into the blood.

Question 13

Locomotion of bivalves and cephalopods.

Answer 13

Bivalves have muscular foot for digging.

Cephalopods (like squid)

Question 14

Feeding characteristics

Answer 14

Radula
Filter feed
Beak

Question 15

Reproduction?

Answer 15

Dioecious (most)

Question 16

Name the 4 class discussed.

Answer 16

Bivalvia

Gastropoda

Polyplacophora

Cephalopoda

Question 17

Chitons (many shells) belongs to?

Answer 17

Polyplacophora

Question 18

Polyplacophora anomaly?

Answer 18

Home scar

Question 19

What was the first mollusk on earth?

Answer 19

Ammonite

Question 20

What class is the most advanced?

Answer 20

Cephalopods with closed circuit system

Question 21

In cephalopods, what is used to communicate?

Answer 21

Chromatophore cells communication is used to camouflage and send messages.

Question 22

What class has internal fertilization?

Answer 22

Cephalopods

Question 23

What is copulation?

Answer 23

Form of internal fertilization. Male uses hectocoytl, left arm, that goes into female’s mantle cavity to release sperm from thespermatophoric sac.

Question 24

What is the difference between octopus and squid?

Answer 24

Octopus - intertidal

Squid - open

Question 25

Chameleons of the sea who has biggest brain to body ratio

Answer 25

Cuttlefish