Phylum Xenoturbellida MCQs January 8, 2026September 28, 2024 by u930973931_answers 30 min Score: 0 Attempted: 0/30 Subscribe 1. Xenoturbellida are primarily classified as: (A) Marine invertebrates (B) Flatworms (C) Mollusks (D) Echinoderms 2. The body of Xenoturbellida is characterized by: (A) Segmentation (B) A complex organ system (C) A hardened exoskeleton (D) Acoelomate structure 3. Xenoturbellids primarily inhabit: (A) Freshwater environments (B) Marine environments (C) Terrestrial habitats (D) Extreme environments 4. The diet of Xenoturbellida mainly consists of: (A) Photosynthetic material (B) Plant matter (C) Detritus and small invertebrates (D) Large fish 5. Xenoturbellida have a simple body plan that lacks: (A) Muscles (B) Organs (C) A digestive system (D) A centralized nervous system 6. The unique feature of Xenoturbellida is their: (A) Ability to regenerate (B) Lack of a gut (C) Bioluminescence (D) Complex reproductive system 7. Xenoturbellida were first discovered in: (A) 1770 (B) 1990 (C) 1950 (D) 2000 8. The class Xenoturbellida is divided into how many families? (A) Two (B) One (C) Three (D) Four 9. The primary mode of locomotion for Xenoturbellida is: (A) Swimming (B) Gliding over surfaces (C) Burrowing into sand (D) Floating 10. Reproduction in Xenoturbellida is primarily: (A) Asexual (B) Fragmentation (C) Sexual (D) Budding 11. Xenoturbellids are known for their: (A) Colorful appearance (B) Fast swimming abilities (C) Large size (D) Simplified body structure 12. The nervous system of Xenoturbellida is described as: (A) Highly developed (B) Absent (C) Diffuse (D) Centralized 13. Xenoturbellida are primarily found at what depth in marine environments? (A) Coral reefs (B) Deep sea (C) Intertidal zones (D) Shallow waters 14. Which of the following best describes the shape of Xenoturbellida? (A) Cylindrical (B) Spherical (C) Flat and ribbon-like (D) Segmented 15. Xenoturbellida lack which structure that is common in many other invertebrates? (A) A body cavity (B) Gills (C) Eyes (D) Tentacles 16. Which of the following is NOT a characteristic of Xenoturbellida? (A) Lack of specialized respiratory structures (B) Simple reproductive methods (C) Presence of complex organ systems (D) Marine habitat 17. Xenoturbellids are thought to have a close evolutionary relationship with: (A) Cnidarians (B) Mollusks (C) Annelids (D) Echinoderms 18. The primary method of feeding for Xenoturbellida is: (A) Suspension feeding (B) Absorbing nutrients through the skin (C) Predation (D) Filter feeding 19. Xenoturbellida exhibit which type of symmetry? (A) Bilateral symmetry (B) Radial symmetry (C) Asymmetry (D) None of the above 20. The phylum Xenoturbellida contains which genus? (A) Nemertea (B) Acoelomorpha (C) Planaria (D) Xenoturbella 21. Which of the following statements is TRUE about Xenoturbellida? (A) They have a simple body organization without true organs. (B) They are known for their rapid regeneration capabilities. (C) They are commonly found in freshwater. (D) They exhibit complex mating behaviors. 22. Xenoturbellida typically reproduce by: (A) Parthenogenesis (B) External fertilization (C) Budding (D) Internal fertilization 23. The classification of Xenoturbellida is primarily based on: (A) Morphological characteristics (B) Genetic studies (C) Behavioral traits (D) All of the above 24. Xenoturbellids are known for their: (A) Hard exoskeletons (B) Soft, gelatinous bodies (C) High mobility (D) Bright coloration 25. The feeding structures of Xenoturbellida are located on the: (A) Head region (B) Posterior end (C) Dorsal surface (D) Ventral surface 26. Xenoturbellids can be found in which of the following environments? (A) All of the above (B) Deep sea vents (C) Coastal marine sediments (D) Intertidal zones 27. Which of the following is a method of locomotion for Xenoturbellida? (A) Swimming with fins (B) Ciliary gliding (C) Using jet propulsion (D) Walking on legs 28. Xenoturbellids exhibit what kind of development? (A) Indirect development (B) Direct development (C) Metamorphosis (D) Asexual reproduction 29. The ecological role of Xenoturbellida in their habitats includes: (A) Predators of larger animals (B) Parasites (C) Primary producers (D) Decomposers 30. Xenoturbellida are sometimes referred to as: (A) Blob-like creatures (B) Sea slugs (C) Ribbon worms (D) Flatworms