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3.4 Echinodermata — Test 1
Q1. The stone canal in Asterias (starfish) connects the:✓ Madreporite with the ring canal
Q2. The connecting link between echinoderms and chordates is:✓ Balanoglossus
Q3. The main organs of respiration in the starfish are the:✓ Papulae (dermal branchiae)
Q4. Aristotle's lantern, a complex chewing apparatus, is well developed in the class:✓ Echinoidea (sea urchins)
Q5. The madreporite, the entry point for the water vascular system, is absent in the class:✓ Holothuroidea (sea cucumbers)
Q6. The bipinnaria and brachiolaria are the larval forms of the class:✓ Asteroidea (starfish)
Q7. The pluteus larva is characteristic of the echinoderm class:✓ Echinoidea (sea urchins)
Q8. The cleavage pattern in the fertilised eggs of echinoderms is:✓ Radial and holoblastic
Q9. The water vascular system, unique to echinoderms, is used mainly for:✓ Locomotion, feeding and gas exchange via tube feet
Q10. Echinoderms are considered close to chordates because both are:✓ Deuterostomes with enterocoely and radial cleavage
Q11. Adult echinoderms show which kind of symmetry?✓ Pentaradial (five-rayed) symmetry
Q12. Tube feet of echinoderms are operated by changes in pressure within the:✓ Water vascular system
Q13. Echinoderms are exclusively:✓ Marine
Q14. The endoskeleton of echinoderms is made of calcareous plates called:✓ Ossicles
Q15. Pedicellariae, small pincer-like structures on the surface of starfish, function to:✓ Keep the surface clean and seize small prey
Q16. Sea cucumbers (Holothuroidea) can defend themselves by:✓ Ejecting sticky internal organs (evisceration)
Q17. Starfish can regenerate lost arms, and in some cases a whole animal can regrow from:✓ A single arm with part of the central disc
Q18. The brittle stars, which move by lashing their flexible arms, belong to the class:✓ Ophiuroidea
Q19. Crinoids (sea lilies and feather stars) differ from other echinoderms in being:✓ Often attached by a stalk with the mouth facing upward
Q20. The mutable connective tissue of echinoderms allows them to:✓ Stiffen or soften the body wall rapidly