- What is the primary characteristic of the class Anthozoa?
- A) They have a polyp form only.
- B) They have a medusa form only.
- C) They are exclusively marine.
- D) They have both polyp and medusa forms.
Answer: A) They have a polyp form only.
- Which of the following is a well-known example of an Anthozoan?
- A) Moon jellyfish
- B) Sea anemone
- C) Box jellyfish
- D) Hydras
Answer: B) Sea anemone
- What type of symmetry do Anthozoans exhibit?
- A) Bilateral symmetry
- B) Radial symmetry
- C) Asymmetry
- D) Pentaradial symmetry
Answer: B) Radial symmetry
- What structure do Anthozoans use for capturing prey?
- A) Tentacles with cnidocytes
- B) Gills
- C) Feeding appendages
- D) Fins
Answer: A) Tentacles with cnidocytes
- Which of the following is a key feature of the gastrovascular cavity in Anthozoans?
- A) It is used for buoyancy.
- B) It is used for digestion and circulation.
- C) It functions in locomotion.
- D) It helps in respiration.
Answer: B) It is used for digestion and circulation.
- What type of reproduction do most Anthozoans primarily use?
- A) Asexual reproduction
- B) Sexual reproduction
- C) Fragmentation
- D) Budding
Answer: B) Sexual reproduction
- What is the role of the mesoglea in Anthozoans?
- A) Digestion
- B) Support and buoyancy
- C) Locomotion
- D) Respiration
Answer: B) Support and buoyancy
- Which of the following types of corals belongs to the class Anthozoa?
- A) Hard corals
- B) Soft corals
- C) Both hard and soft corals
- D) Neither
Answer: C) Both hard and soft corals
- Which of the following is a mutualistic relationship often found in Anthozoans?
- A) Anthozoans and zooxanthellae
- B) Anthozoans and sharks
- C) Anthozoans and fish
- D) Anthozoans and sea turtles
Answer: A) Anthozoans and zooxanthellae
- What is the primary habitat of most Anthozoans?
- A) Freshwater
- B) Marine environments
- C) Terrestrial environments
- D) Estuaries
Answer: B) Marine environments
- What is the larval stage of Anthozoans called?
- A) Planula
- B) Ephyra
- C) Polyp
- D) Medusa
Answer: A) Planula
- Which feature is common among all Anthozoans?
- A) Presence of a medusa stage
- B) Simple body structure with a central mouth
- C) Ability to swim actively
- D) Rigid external skeleton
Answer: B) Simple body structure with a central mouth
- Which of the following is NOT a subclass of Anthozoa?
- A) Hexacorallia
- B) Octocorallia
- C) Scyphozoa
- D) Ceriantharia
Answer: C) Scyphozoa
- What do Anthozoans primarily feed on?
- A) Algae
- B) Small fish and zooplankton
- C) Detritus
- D) Larger marine mammals
Answer: B) Small fish and zooplankton
- How do Anthozoans typically respond to stimuli?
- A) Complex nervous system
- B) Simple nerve net
- C) Fast locomotion
- D) Color change
Answer: B) Simple nerve net
- What is a significant ecological role of Anthozoans in marine ecosystems?
- A) Primary producers
- B) Habitat formation for other species
- C) Decomposers
- D) Predators
Answer: B) Habitat formation for other species
- Which type of coral reef is primarily built by hard corals from the class Anthozoa?
- A) Atoll reefs
- B) Fringing reefs
- C) Barrier reefs
- D) All of the above
Answer: D) All of the above
- What is the main composition of coral reefs formed by Anthozoans?
- A) Calcium carbonate
- B) Silica
- C) Organic matter
- D) Sand
Answer: A) Calcium carbonate
- What unique feature do some Anthozoans have that aids in defense?
- A) Camouflage
- B) Bioluminescence
- C) Stinging cells (nematocysts)
- D) Speed
Answer: C) Stinging cells (nematocysts)
- Which of the following is a characteristic of soft corals?
- A) Hard skeleton
- B) Flexible structure
- C) Live in deep waters only
- D) Lack symbiotic relationships
Answer: B) Flexible structure
- What is the significance of zooxanthellae to Anthozoans?
- A) They provide food through photosynthesis.
- B) They aid in reproduction.
- C) They help with locomotion.
- D) They provide protection from predators.
Answer: A) They provide food through photosynthesis.
- Which of the following is an adaptation of Anthozoans for survival in their environment?
- A) High mobility
- B) Stinging cells for prey capture
- C) Rigid exoskeleton
- D) Ability to burrow
Answer: B) Stinging cells for prey capture
- What is a common reproductive method for many Anthozoans?
- A) Fragmentation
- B) Budding
- C) Both A and B
- D) Sexual reproduction only
Answer: C) Both A and B
- Which of the following best describes the relationship between corals and reef ecosystems?
- A) Corals are non-essential.
- B) Corals are foundational species.
- C) Corals harm other species.
- D) Corals are primary consumers.
Answer: B) Corals are foundational species.
- What type of environment do most Anthozoans thrive in?
- A) Deep sea trenches
- B) Shallow, warm waters
- C) Polar regions
- D) Freshwater lakes
Answer: B) Shallow, warm waters
- Which subclass of Anthozoa includes the sea pens?
- A) Hexacorallia
- B) Octocorallia
- C) Ceriantharia
- D) Scyphozoa
Answer: B) Octocorallia
- What is the primary cause of coral bleaching in Anthozoans?
- A) Overfishing
- B) Temperature stress
- C) Pollution
- D) All of the above
Answer: B) Temperature stress
- What feature distinguishes hard corals from soft corals?
- A) Presence of nematocysts
- B) Formation of calcium carbonate skeletons
- C) Habitat preferences
- D) Feeding habits
Answer: B) Formation of calcium carbonate skeletons
- How do Anthozoans obtain nutrients?
- A) Photosynthesis
- B) Absorption through the skin
- C) Ingestion of prey
- D) Both A and C
Answer: D) Both A and C
- What is a major threat to Anthozoan populations worldwide?
- A) Habitat destruction
- B) Invasive species
- C) Climate change
- D) All of the above
Answer: D) All of the above