EXAM 2

Question 1

Why do we care about mollusks?

Answer 1

Important for:
-Water quality
-Problematic Invaders
-Changing abundances
-Important fisheries

Question 2

Where do mollusk live?

Answer 2

Marine, freshwater, or terrestrial

Question 3

2 Big picture characteristics of mollusks

Answer 3

1. Eucoelomate
   2.Protostome (blastopore mouth)

Question 4

7 Mulluscan characteristics?

Answer 4

1. Unsegmented body
2. Head
3. Foot
   4, Visceral mass
4. Calcareous shell (In some cases)
5. Mantle
6. Radula

Question 5

What is the FOOT used for in mollusks?

Answer 5

-Usually ventral
-Attachment to substrate
-Locomotion

Question 6

Foot burrowing process in clams (A-D)

Answer 6

A. Valves open, circular muscles contract, foot extended
B. Anchor forms, valves squirt water into sand
C. Anterior pedal retractors contract
D. Posterior pedal retractors begin rocking motion

Question 7

What is found in visceral mass? (1-4)

Answer 7

1. Digestive organs
2. Reproductive organs
3. Circulatory organs
4. Respiratory organs

Question 8

What is the mantle?

Answer 8

-Sheet-like organ
-Forms dorsal body wall
-Secretes Shell

Question 9

How to mollusks make their shell?

Question 10

Shell plasticity with predators (Crab, seastar, both)

Answer 10

Crab: Thicker, robust shell
Sea star: Formed longer shell, with greater internal volume. (Withdraws in)
Both: Snails respond to crab more

Question 11

What is the radula?

Answer 11

Tongue-like organ rows of tiny teeth for scraping food from surfaces