Mollusca is a large phylum of invertebrate animals that includes snails, clams, oysters, and octopuses, as well as several other types of animals. Mollusks are characterized by their soft bodies and the presence of a mantle, which is a layer of tissue that covers their internal organs and often secretes a shell. Most mollusks also have a muscular foot that they use for movement and a radula, which is a ribbon-like structure used for feeding. Mollusks are found in a variety of habitats, including land, freshwater, and marine environments.
1. What is the largest class within the phylum Mollusca?
A) Bivalvia
B) Gastropoda
C) Cephalopoda
D) Scaphopoda
Answer: C) Cephalopoda
2. Which of the following is NOT a characteristic of mollusks?
A) A mantle
B) A muscular foot
C) A hard exoskeleton
D) A radula
Answer: C) A hard exoskeleton
3. What is the main difference between a bivalve and a gastropod?
A) Bivalves have a head, while gastropods do not
B) Bivalves have a hinged shell, while gastropods do not
C) Bivalves are herbivores, while gastropods are carnivores
D) Bivalves are sessile, while gastropods are mobile
Answer: B) Bivalves have a hinged shell, while gastropods do not
4. What is the function of the radula in mollusks?
A) To aid in digestion
B) To move the mollusk through water
C) To defend against predators
D) To help the mollusk cling to surfaces
Answer: A) To aid in digestion
5. Which of the following is NOT a type of mollusk?
A) Clam
B) Snail
C) Octopus
D) Spider
Answer: D) Spider
6. What is the primary habitat of mollusks?
A) Land
B) Freshwater
C) Marine
D) All of the above
Answer: D) All of the above
7. What is the main function of the mantle in mollusks?
A) To protect the mollusk’s internal organs
B) To aid in movement
C) To produce shells
D) To aid in respiration
Answer: C) To produce shells
8. How do mollusks reproduce?
A) Asexually through fission
B) Asexually through budding
C) Sexually through external fertilization
D) Sexually through internal fertilization
Answer: D) Sexually through internal fertilization
9. Which of the following is NOT a type of cephalopod?
A) Squid
B) Nautilus
C) Cuttlefish
D) Jellyfish
Answer: D) Jellyfish
10. Which of the following is NOT a characteristic of cephalopods?
A) The ability to swim quickly
B) The ability to change color rapidly
C) The presence of tentacles
D) The ability to fly
Answer: D) The ability to fly
