Structural Organisation in Animals Mock Test – Class 11 Biology

1. Relate each earthworm-related activity with its principal ecological or practical outcome. Each Column II entry is used once.

2. Use the posterior male arrangement described below. Chamber P is bounded dorsally by the ninth and tenth terga and ventrally by the ninth sternum. A male gonopore and external genital structures are associated with this region. Chamber P is:

3. The usual external colour pattern of a frog is:

4. Let represent frog body temperature and environmental temperature. Which relation expresses poikilothermy without claiming exact equality at every moment?

5. Calciferous glands in the stomach stop secreting, but the gizzard remains fully functional. The expected pattern is:

6. A labelled nitrogenous compound is introduced into the haemolymph of two groups of cockroaches. In controls, the label later appears in Malpighian tubules and then in the hindgut. In treated animals, tubular uptake is blocked, and little label reaches the hindgut despite normal gut movement. The strongest conclusion is:

7. The common duct carrying bile and pancreatic juice into the duodenum becomes completely blocked. Which outcome is most directly expected?

8. A stomach lining is formed by a single layer of tall slender cells whose nuclei lie nearer the basal region. The free surface is specialised for secretion and absorption. This description identifies:

9. Neuroglia are selectively destroyed in a region while most neurons remain structurally present and initially excitable. The most defensible prediction is:

10. The integrated records below describe cockroach organ systems.

The record requiring correction is:

11. Equal earthworms are placed on the same moist rough surface. In treatment P, the setae are temporarily immobilised inside their pits without damaging the muscles; control worms retain normal setal movement. Treatment P shows strong body contractions but little forward progress. The strongest inference is:

12. Assertion: The prostomium assists an earthworm during burrowing.
Reason: It projects near the mouth and acts as a wedge against the soil.

13. A lining consists of one cell layer and permits exchange across a cavity wall, whereas a second lining has several layers and resists repeated abrasion. The pair is best completed as:

14. Compare a cockroach nymph with an adult.

Which conclusion is best supported?

15. A mature earthworm has segments, and its clitellum occupies segments . How many segments belong to the postclitellar region?

16. Four preparations are provisionally classified from their observed features.

The pair that requires reclassification is:

17. In a multicellular animal, specialised cell groups remain structurally intact, but communication and material exchange among them fail. The most likely organism-level outcome is:

18. Four connective-tissue samples are summarised below.

Sample P is best interpreted as:

19. An earthworm ingests soil containing coarse particles and a high amount of humic acid. Normal processing of this material depends most directly on:

20. Assertion: Earthworm haemoglobin can contribute to respiratory-gas transport while remaining dissolved in plasma.
Reason: In the earthworm blood described here, haemoglobin is not restricted within red blood cells.

21. One circumpharyngeal branch connecting the ventral nerve cord with the cerebral ganglia is severed, while the opposite branch remains intact. Which conclusion is most defensible?

22. Place the following events involved in formation and transfer of a cockroach spermatophore.
P. Sperm is stored in the seminal vesicles.
Q. Sperm is produced in the testes.
R. A sperm-containing spermatophore is formed with accessory-gland contribution.
S. The spermatophore is transferred through the male genital region.

23. Review the statements given below about simple cuboidal epithelium.
I. Its cells are approximately cube-like.
II. It commonly occurs in gland ducts and tubular parts of nephrons.
III. Proximal convoluted tubule cells lack surface microvilli.
IV. Secretion and absorption are important functions.

24. External nephridiopores are blocked without affecting nephridia that discharge into the intestine. The most direct consequence is:

25. Smooth muscle in a section of the intestinal wall becomes unable to contract, while the epithelial lining and connective support remain intact. The most direct effect is:

26. A harmless coating keeps an earthworm’s surface moist but is nearly impermeable to respiratory gases. The hearts continue beating and the blood glands remain functional. The most likely outcome is:

27. Examine the statements below about the earthworm body wall.
I. The cuticle is a thin non-cellular covering.
II. The epidermis is a single layer of columnar cells containing secretory gland cells.
III. Longitudinal muscle lies external to circular muscle.
IV. Coelomic epithelium forms the innermost layer.

28. Sequence the following events in one simplified cycle of setae-assisted earthworm locomotion.
P. Selected setae project and grip the soil.
Q. Muscular action displaces another part of the body relative to the anchored region.
R. The gripping setae retract.
S. A new region establishes anchorage for the next movement.

29. Equal frogs are kept under the same temperature. Group P has normal moist skin, while a harmless surface treatment in Group Q prevents water from passing through the skin without blocking air movement. Q shows reduced body-water gain despite access to a wet surface. The strongest inference is:

30. Order the following regions from the anterior brain toward the posterior nervous pathway.
P. Forebrain
Q. Midbrain
R. Hindbrain
S. Spinal cord

31. Let and denote the segments bearing the female genital pore and male genital pores, respectively. The valid positional relation is:

32. An earthworm has segments, and its typhlosole is absent from the last segments. Assuming the fold is otherwise present posterior to segment , the last segment containing the typhlosole is:

33. A female cockroach specimen has paired ovaries extending through abdominal segments . Each ovary leads into a lateral oviduct, and the two oviducts join a median vagina. This arrangement most directly supports:

34. Place the events involved in ciliary transport along an epithelial surface.
P. Material trapped in the surface fluid moves toward a particular destination.
Q. Cilia on the free surface beat in a coordinated direction.
R. The adjoining layer of mucus or fluid is displaced.

35. Assertion: Dense irregular connective tissue is well suited to the skin.
Reason: Its collagen fibres run in varied orientations and can resist mechanical stress arriving from different directions.

36. Interpret the arrangement described below. A continuous sheet has closely packed cells, very little material between them, and one surface facing a cavity containing body fluid. This sheet is best identified as:

37. Two cultures of adjacent epithelial cells are prepared. In treatment P, gap junctions are selectively blocked; in the control, all junctions remain intact. A signal introduced into one cell rapidly influences neighbouring control cells but not neighbouring cells in P. The strongest conclusion is:

38. Relate each cell commonly found in areolar tissue with its principal contribution. Each Column II entry is used once.

39. A dissected frog has paired gonads near the kidneys, no mesorchia or vasa efferentia, and paired reproductive ducts opening separately into the cloaca. The specimen is most consistently identified as:

40. A multicellular animal has stable tissues and recognisable organs, but its organs neither exchange materials nor communicate with one another. The claim that fails most directly is that the animal has:

41. A treatment affects every segment from through , including both boundary segments. Which canal region is directly involved, and across how many segments does the treatment extend?

42. Interpret the internal arrangement described below. Structures P are paired reproductive organs lying near the kidneys but having no functional connection with them. Structures Q are paired ducts that conduct reproductive material independently and open into the cloaca. P and Q are:

43. Examine the sensory records below.

The record requiring correction is:

44. Evaluate the following statements about the male reproductive organs of a frog.
I. The testes are paired, yellowish, and ovoid.
II. They lie attached to the upper parts of the kidneys.
III. The attachment is formed by a double fold of peritoneum called the mesorchium.
IV. The testes lie freely inside the cloaca.

45. Two identical uncovered food samples are placed overnight in separate chambers. Cockroaches previously allowed to move over contaminated refuse enter Chamber P, while Chamber Q remains cockroach-free. Bacterial growth is later much higher on the food in P. The strongest supported conclusion is:

46. The forewings and hind wings of a cockroach share a thoracic origin but differ in structure and role. Which relation is correct?

47. Assertion: Endocrine glands are described as ductless glands.
Reason: Their hormones are released into the fluid bathing the gland rather than being carried through a glandular duct.

48. Assertion: Ciliated epithelium may be formed from cuboidal or columnar cells.
Reason: Cilia move mucus, particles, or other material in a definite direction over the epithelial surface.

49. Pair each cartilage-related feature with its description. Each Column II entry is used once.

50. The route records below are evaluated.

Which record requires correction?