TRB PG Assistant - Minor phyla – Ctenophora, Rotifera, Chaetognatha, Onychophora, Siphunculida, Entoprocta, Ectoprocta, Phoronida Online Test (MCQ Quiz)

1. Which phylum is characterized by the presence of comb plates (ctenes) for locomotion and biradial symmetry?

A) Rotifera B) Ctenophora C) Chaetognatha D) Onychophora

2. Members of the phylum Ctenophora are commonly known as:

A) Wheel animals B) Arrow worms C) Comb jellies D) Velvet worms

3. What unique feature do Ctenophores possess for capturing prey, typically consisting of colloblasts or tentacles?

A) Radula B) Pedal disc C) Ctenidia D) Colloblasts

4. The body plan of Ctenophora exhibits:

A) Bilateral symmetry B) Radial symmetry C) Biradial symmetry D) Asymmetry

5. Which phylum is characterized by a corona, a ciliated structure used for both locomotion and feeding?

A) Ctenophora B) Rotifera C) Chaetognatha D) Siphunculida

6. Rotifers are commonly referred to as:

A) Comb jellies B) Peanut worms C) Wheel animals D) Arrow worms

7. The characteristic feeding apparatus in Rotifera used to sweep food particles into the mouth is called the:

A) Proboscis B) Mastax C) Radula D) Siphon

8. Many species of Rotifera exhibit parthenogenesis. What does this mean?

A) They reproduce only sexually. B) Females produce offspring from unfertilized eggs. C) They are hermaphroditic. D) They have a larval stage that is free-swimming.

9. Which phylum consists of small, planktonic marine predators with a distinctive arrow-like shape and a grasping apparatus?

A) Rotifera B) Ctenophora C) Chaetognatha D) Entoprocta

10. Chaetognaths are commonly known as:

A) Velvet worms B) Peanut worms C) Arrow worms D) Moss animals

11. The grasping spines used by Chaetognaths for capturing prey are located around the:

A) Anus B) Mouth C) Pharynx D) Nerve ring

12. Chaetognaths are important components of marine ecosystems primarily as:

A) Detritivores B) Primary producers C) Secondary consumers D) Decomposers

13. Which phylum contains terrestrial, soft-bodied, centipede-like animals with unjointed legs and a segmented body covered by a cuticle?

A) Chaetognatha B) Siphunculida C) Onychophora D) Ectoprocta

14. Onychophorans are often called:

A) Arrow worms B) Peanut worms C) Wheel animals D) Velvet worms

15. A distinctive feature of Onychophora is the presence of slime glands that secrete a sticky substance for:

A) Respiration B) Defense and prey capture C) Excretion D) Locomotion

16. The circulatory system in Onychophora is:

A) Closed, with arteries and veins B) Open, with a dorsal heart and sinuses C) Absent D) Partially closed

17. Which phylum comprises marine, unsegmented worms with a retractable, muscular proboscis used for burrowing and feeding?

A) Onychophora B) Entoprocta C) Siphunculida D) Phoronida

18. Siphunculids are commonly known as:

A) Velvet worms B) Peanut worms C) Arrow worms D) Comb jellies

19. The anterior end of a Siphunculid, bearing the mouth and the retractable proboscis, is called the:

A) Anus B) Uvula C) Nuchal organ D) Tentacular crown

20. Siphunculids are typically:

A) Pelagic plankton B) Free-swimming predators C) Benthic burrowers D) Parasites

21. Which phylum consists of small, sessile, colonial or solitary marine animals with a characteristic calyx (cup-shaped body) and a retractile stalk?

A) Siphunculida B) Ectoprocta C) Entoprocta D) Chaetognatha

22. Entoprocts are sometimes called:

A) Moss animals B) Peanut worms C) Wheel animals D) Arrow worms

23. In Entoprocta, the anus is located:

A) Outside the circlet of tentacles B) Inside the circlet of tentacles C) At the posterior end D) On the ventral side

24. Entoprocts reproduce both sexually and asexually. Asexual reproduction typically occurs via:

A) Budding B) Parthenogenesis C) Binary fission D) Fragmentation

25. Which phylum consists of sessile, colonial, aquatic invertebrates that typically form encrusting or branching colonies and are often called 'moss animals'?

A) Entoprocta B) Phoronida C) Ectoprocta D) Ctenophora

26. Ectoprocts are also commonly known as:

A) Wheel animals B) Arrow worms C) Moss animals D) Velvet worms

27. A distinguishing feature of Ectoprocta is that the anus is located:

A) Inside the lophophore B) Outside the lophophore C) Within the U-shaped gut D) On the dorsal surface of the zooid

28. The feeding structure in Ectoprocta, a horseshoe-shaped or circular arrangement of ciliated tentacles, is called the:

A) Corona B) Lophophore C) Mastax D) Proboscis

29. Ectoprocts are members of which larger superphylum, characterized by the presence of a lophophore?

A) Ecdysozoa B) Lophotrochozoa C) Deuterostomia D) Protostomia

30. Which phylum contains sessile, worm-like marine animals that live in chitinous tubes and possess a U-shaped lophophore for feeding?

A) Ectoprocta B) Siphunculida C) Phoronida D) Rotifera

31. Phoronids are commonly known as:

A) Horseshoe worms B) Arrow worms C) Wheel animals D) Moss animals

32. The body of Phoronids is divided into two regions: a shorter anterior section bearing the lophophore and a longer posterior section that:

A) Contains the digestive system B) Is responsible for reproduction C) Houses the anus D) Secretes the tube

33. Phoronids possess a unique blood-vascular system with a dorsal and ventral blood vessel and a:

A) Gills B) Hemocoel C) Heart D) Metanephridia

34. Which of the following is NOT a characteristic feature of Ctenophora?

A) Comb plates for locomotion B) Nematocysts for stinging C) Biradial symmetry D) Colloblasts for prey capture

35. The mastax in Rotifera is homologous to which structure in other invertebrates?

A) Radula B) Pharynx C) Esophagus D) Stomach

36. Which phylum exhibits a nervous system with a distinct cerebral ganglion and a ladder-like arrangement of nerves in the body wall?

A) Ctenophora B) Rotifera C) Chaetognatha D) Onychophora

37. The proboscis of Siphunculida is used for:

A) Swimming B) Defense C) Ingesting food and burrowing D) Reproduction

38. A key difference between Entoprocta and Ectoprocta lies in the position of the anus relative to the:

A) Mouth B) Lophophore C) Stomach D) Intestine

39. The symbiotic relationship between Phoronids and certain algae within their tubes is an example of:

A) Predation B) Parasitism C) Commensalism D) Mutualism

40. Which phylum is considered a 'living fossil' due to its ancient lineage and unique morphological features, bridging annelids and arthropods?

A) Siphunculida B) Onychophora C) Chaetognatha D) Rotifera

41. The larval stage of some Rotifers, known as the amictic egg, develops into:

A) Males B) Females capable of parthenogenesis C) Females capable of sexual reproduction D) Diapause eggs

42. The nervous system of Chaetognaths is considered relatively simple, consisting of a cerebral ganglion and a ventral nerve cord with:

A) Segmental ganglia B) Dorsal nerve cord C) No lateral nerves D) A nerve net

43. The presence of metanephridia for excretion is characteristic of which of the following minor phyla?

A) Ctenophora B) Rotifera C) Siphunculida D) Chaetognatha

44. In Ectoprocta, the individual units forming the colony are called:

A) Zooids B) Polyps C) Individuals D) Zooids

45. The body cavity of Phoronids is a:

A) Pseudocoelom B) Coelom C) Hemocoel D) Acoelom

46. Which phylum is characterized by a complete digestive system and a hydrostatic skeleton, enabling burrowing in soft substrates?

A) Ctenophora B) Rotifera C) Siphunculida D) Onychophora

47. The 'corona' in Rotifera serves the dual purpose of:

A) Digestion and excretion B) Respiration and circulation C) Feeding and locomotion D) Sensing and defense

48. Which phylum lacks a true coelom and exhibits a simple body plan with a U-shaped digestive tract?

A) Ctenophora B) Rotifera C) Chaetognatha D) Entoprocta

49. The 'arrow worm' body plan is adapted for:

A) Bottom dwelling and filter feeding B) Planktonic predation C) Burrowing in sand D) Colonial life

50. The segmented body and unjointed appendages of Onychophora suggest a possible evolutionary link between:

A) Mollusca and Echinodermata B) Annelida and Arthropoda C) Cnidaria and Porifera D) Chordata and Hemichordata

Minor phyla – Ctenophora, Rotifera, Chaetognatha, Onychophora, Siphunculida, Entoprocta, Ectoprocta, Phoronida - Online Test

Test Results