- What is the primary characteristic of Osteichthyes?
- A) They have a cartilaginous skeleton.
- B) They have a bony skeleton.
- C) They are warm-blooded.
- D) They possess gills only.
Answer: B) They have a bony skeleton.
- Which of the following is a subclass of Osteichthyes?
- A) Elasmobranchii
- B) Actinopterygii
- C) Agnatha
- D) Chondrichthyes
Answer: B) Actinopterygii
- What type of fish is primarily found in the class Osteichthyes?
- A) Sharks
- B) Ray-finned fish
- C) Lampreys
- D) Sturgeons
Answer: B) Ray-finned fish
- Which of the following is NOT a characteristic of Osteichthyes?
- A) Swim bladder
- B) Bony skeleton
- C) Gills covered by operculum
- D) Lack of fins
Answer: D) Lack of fins
- What is the function of the swim bladder in Osteichthyes?
- A) Digestion
- B) Buoyancy control
- C) Respiration
- D) Reproduction
Answer: B) Buoyancy control
- Which of the following fish belongs to the Osteichthyes class?
- A) Hammerhead shark
- B) Catfish
- C) Manta ray
- D) Nurse shark
Answer: B) Catfish
- What structure do Osteichthyes use to breathe?
- A) Lungs
- B) Gills
- C) Skin
- D) Swim bladder
Answer: B) Gills
- Which of the following adaptations is common in Osteichthyes?
- A) Cartilage skeleton
- B) Operculum
- C) Lack of scales
- D) Warm-bloodedness
Answer: B) Operculum
- What type of reproduction do most Osteichthyes exhibit?
- A) Oviparous
- B) Viviparous
- C) Ovoviviparous
- D) All of the above
Answer: D) All of the above
- Which of the following is a method Osteichthyes use to find food?
- A) Hunting in packs
- B) Filter feeding
- C) Grazing on algae
- D) All of the above
Answer: D) All of the above
- Which of the following is a feature of bony fish?
- A) Reduced size of the dorsal fin
- B) Presence of a swim bladder
- C) Absence of scales
- D) Cartilaginous jaws
Answer: B) Presence of a swim bladder
- What type of scales do many Osteichthyes have?
- A) Placoid scales
- B) Ganoid scales
- C) Cycloid or ctenoid scales
- D) All of the above
Answer: C) Cycloid or ctenoid scales
- Which of the following is a significant advantage of a bony skeleton?
- A) Increased flexibility
- B) Enhanced buoyancy
- C) Greater strength
- D) Improved maneuverability
Answer: C) Greater strength
- What is the main purpose of the lateral line system in Osteichthyes?
- A) Navigation
- B) Detecting vibrations and movement in water
- C) Breathing
- D) Feeding
Answer: B) Detecting vibrations and movement in water
- Which of the following is a primary diet type for many Osteichthyes?
- A) Herbivorous
- B) Carnivorous
- C) Omnivorous
- D) All of the above
Answer: D) All of the above
- What is the typical body shape of most Osteichthyes?
- A) Flat
- B) Cylindrical or streamlined
- C) Boxy
- D) Irregular
Answer: B) Cylindrical or streamlined
- Which of the following is NOT a feature of the Actinopterygii subclass?
- A) Ray-finned
- B) Lobe-finned
- C) Cartilaginous skeleton
- D) Operculum
Answer: C) Cartilaginous skeleton
- What organ helps Osteichthyes with their buoyancy?
- A) Gills
- B) Liver
- C) Swim bladder
- D) Heart
Answer: C) Swim bladder
- Which of the following adaptations helps Osteichthyes with swimming efficiency?
- A) Dorsal fins
- B) Pectoral fins
- C) Tail fins
- D) All of the above
Answer: D) All of the above
- Which group of Osteichthyes is known for having lobed fins?
- A) Actinopterygii
- B) Elasmobranchii
- C) Sarcopterygii
- D) Agnatha
Answer: C) Sarcopterygii
- What type of scales are found in the fish of the subclass Actinopterygii?
- A) Placoid scales
- B) Ganoid scales
- C) Cycloid scales
- D) Both B and C
Answer: D) Both B and C
- Which of the following is a common example of a bony fish?
- A) Tuna
- B) Shark
- C) Skate
- D) Lamprey
Answer: A) Tuna
- Which of the following adaptations allows Osteichthyes to live in various aquatic environments?
- A) Flexible bodies
- B) Ectothermic metabolism
- C) Variety of feeding strategies
- D) All of the above
Answer: D) All of the above
- How do Osteichthyes usually reproduce?
- A) External fertilization
- B) Internal fertilization
- C) Both external and internal fertilization
- D) Asexual reproduction
Answer: C) Both external and internal fertilization
- What helps Osteichthyes to detect food in murky waters?
- A) Their eyes
- B) Their gills
- C) Their lateral line system
- D) Their nostrils
Answer: C) Their lateral line system
- Which of the following features helps to protect the gills of Osteichthyes?
- A) Scales
- B) Operculum
- C) Fins
- D) Swim bladder
Answer: B) Operculum
- What kind of circulatory system do Osteichthyes possess?
- A) Open circulatory system
- B) Closed circulatory system
- C) None
- D) Both A and B
Answer: B) Closed circulatory system
- Which of the following is a major ecological role of Osteichthyes?
- A) They are primary producers.
- B) They serve as prey for larger animals.
- C) They are decomposers.
- D) They have no ecological role.
Answer: B) They serve as prey for larger animals.
- What is the primary sensory organ used by Osteichthyes to detect chemical changes in the water?
- A) Eyes
- B) Nostrils
- C) Lateral line system
- D) Ears
Answer: B) Nostrils
- What is a common threat to Osteichthyes populations worldwide?
- A) Overfishing
- B) Pollution
- C) Habitat loss
- D) All of the above
Answer: D) All of the above