Structural Organisation in Animals

20 NEET-UG practice questions on Structural Organisation in Animals, part of Zoology. The first 20 are below; the first 5 with answers and explanations (tap Show answer after you have chosen), the rest in Learn with a free account.

1. Question 1 · Hard

   Match List-I with List-II. List-I (cell) A. Fibroblast B. Osteocyte C. Chondrocyte D. Goblet cell List-II (description) I. Enclosed in small cavities within a pliable matrix that resists compression II. Secretes mucus as a single-celled gland III. Produces and secretes fibres in areolar tissue IV. Lies in a lacuna within a hard matrix rich in calcium salts

   1. AA-III, B-IV, C-I, D-II
   2. BA-II, B-IV, C-I, D-III
   3. CA-I, B-IV, C-III, D-II
   4. DA-III, B-I, C-IV, D-II

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   Answer: A · A-III, B-IV, C-I, D-II

   Fibroblasts make fibres in areolar tissue, and goblet cells secrete mucus. Osteocytes sit in lacunae of hard, calcium-rich bone, whereas chondrocytes sit in cavities of solid but pliable cartilage.

   • B: This swaps the fibre producer and the mucus cell.
   • C: This swaps the fibroblast and the chondrocyte.
   • D: This swaps bone cells and cartilage cells.

   Remember this

   Bone is hard and non-pliable with lacunae; cartilage is pliable and resists compression.

2. Question 2 · Medium

   Given below are two statements: Statement I: In all connective tissues except blood, the cells secrete fibres of structural proteins called collagen or elastin. Statement II: Most cartilages of vertebrate embryos are replaced by bones in adults. Choose the correct answer.

   1. AStatement I is correct but Statement II is incorrect
   2. BBoth Statement I and Statement II are incorrect
   3. CBoth Statement I and Statement II are correct
   4. DStatement I is incorrect but Statement II is correct

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   Answer: C · Both Statement I and Statement II are correct

   Both statements match NCERT. Blood is the one connective tissue that does not secrete fibres, and embryonic cartilage is largely replaced by bone.

   • A: Statement II is true.
   • B: Both statements are true.
   • D: Statement I is true.

   Remember this

   Blood is a fluid connective tissue, and its cells secrete no collagen or elastin fibres.

3. Question 3 · Easy

   Walls of blood vessels and air sacs of lungs are lined by

   1. Aciliated columnar epithelium
   2. Bcompound epithelium
   3. Csimple squamous epithelium
   4. Dsimple cuboidal epithelium

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   Answer: C · simple squamous epithelium

   A single thin layer of flattened cells forms a diffusion boundary, which suits blood vessels and air sacs. This is simple squamous epithelium.

   • A: Ciliated cells line bronchioles and fallopian tubes.
   • B: Compound layers are too thick for a diffusion boundary.
   • D: Cuboidal cells line gland ducts and nephron tubules.

   Remember this

   Squamous epithelium is for diffusion; cuboidal and columnar are for secretion and absorption.

4. Question 4 · Easy

   A goblet cell of the alimentary canal is an example of

   1. Amulticellular glandular epithelium
   2. Bcompound epithelium
   3. Cciliated epithelium
   4. Dunicellular glandular epithelium

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   Answer: D · unicellular glandular epithelium

   The goblet cell is a single secretory cell, so it is a unicellular gland. Salivary glands are the multicellular example.

   • A: Salivary glands, not goblet cells, are multicellular.
   • B: A goblet cell lies in a single-layered lining.
   • C: A goblet cell secretes and does not beat cilia.

   Remember this

   Goblet cell is unicellular; salivary gland is multicellular.

5. Question 5 · Hard

   Read these statements about epithelia and cell junctions: A. Tight junctions stop substances from leaking across a tissue. B. Adhering junctions keep neighbouring cells together. C. Exocrine glands are ductless and pour secretions into the fluid bathing the gland. D. Gap junctions act mainly to cement neighbouring cells. Which of these are correct?

   1. AA and B only
   2. BA, B and D only
   3. CA, B and C only
   4. DB and D only

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   Answer: A · A and B only

   A and B are the correct roles. Being ductless describes endocrine glands, so C fails. Cementing is the job of adhering junctions, while gap junctions connect cytoplasm, so D fails.

   • B: D gives gap junctions the adhering role.
   • C: C describes endocrine glands, not exocrine.
   • D: D is false, and A is true.

   Remember this

   Exocrine glands release through ducts; endocrine glands are ductless.

6. Question 6 · Hard

   Given below are two statements: Statement I: Cardiac muscle cells contract as a unit because communication junctions at their fusion points pass a signal from one cell to the next. Statement II: Compound epithelium is specialised mainly for secretion and absorption, because it has many layers of cells. Choose the correct answer.

   1. ABoth Statement I and Statement II are correct
   2. BStatement I is incorrect but Statement II is correct
   3. CStatement I is correct but Statement II is incorrect
   4. DBoth Statement I and Statement II are incorrect

   Answer and explanation in LearnFree account

7. Question 7 · Hard

   Consider these statements about a frog: A. The male has vocal sacs and a copulatory pad. B. It has a hepatic portal system but no renal portal system. C. Ten pairs of cranial nerves arise from its brain. D. It excretes urea and so is ureotelic. Choose the correct answer.

   1. AB, C and D only
   2. BA, C and D only
   3. CA and C only
   4. DA, B and D only

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8. Question 8 · Medium

   Arrange the structures in the order in which sperms pass through them in a male frog. A. Bidder's canal B. Vasa efferentia C. Urinogenital duct D. Cloaca

   1. AB, C, A, D
   2. BB, A, C, D
   3. CA, B, C, D
   4. DC, B, A, D

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9. Question 9 · Medium

   Fibroblasts, macrophages and mast cells occur together in

   1. Acartilage
   2. Badipose tissue
   3. Cbone
   4. Dareolar tissue

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10. Question 10 · Medium

    Which site is lined by compound epithelium?

    1. AAir sacs of the lungs
    2. BInner lining of the fallopian tubes
    3. CInner wall of blood vessels
    4. DMoist surface of the pharynx

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11. Question 11 · Medium

    In an experiment, a small fluorescent dye injected into one cell of an animal tissue quickly appears in the next cell, passing through channels that connect their cytoplasm. These channels are

    1. Aplasmodesmata
    2. Badhering junctions
    3. Cgap junctions
    4. Dtight junctions

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12. Question 12 · Medium

    Match List-I with List-II. List-I (tissue) A. Dense irregular connective tissue B. Adipose tissue C. Cartilage D. Smooth muscle List-II (location) I. Tip of the nose II. Wall of the intestine III. Skin IV. Beneath the skin, as a fat store

    1. AA-III, B-IV, C-II, D-I
    2. BA-IV, B-III, C-I, D-II
    3. CA-III, B-IV, C-I, D-II
    4. DA-I, B-IV, C-III, D-II

    Answer and explanation in LearnFree account

13. Question 13 · Medium

    Match List-I with List-II. List-I (structure in frog) A. Copulatory pad B. Bidder's canal C. Sinus venosus D. Conus arteriosus List-II (feature) I. Receives blood from the ventricle, on the ventral side of the heart II. Receives vasa efferentia inside the kidney III. Receives blood through the vena cava and joins the right atrium IV. Found on the first digit of the male forelimb

    1. AA-IV, B-III, C-II, D-I
    2. BA-IV, B-II, C-III, D-I
    3. CA-IV, B-II, C-I, D-III
    4. DA-II, B-IV, C-III, D-I

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14. Question 14 · Easy

    Count the digits on the limbs of a frog. What does the count show?

    1. AFive on each forelimb and five on each hindlimb
    2. BFive on each forelimb and four on each hindlimb
    3. CFour on each forelimb and four on each hindlimb
    4. DFour on each forelimb and five on each hindlimb

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15. Question 15 · Medium

    Cuboidal epithelium bearing microvilli on its free surface lines the

    1. Adry surface of the skin
    2. Bair sacs of the lungs
    3. Cbronchioles of the lungs
    4. Dproximal convoluted tubule

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16. Question 16 · Easy

    Intercalated discs are a feature of

    1. Askeletal muscle
    2. Bcardiac muscle
    3. Cadipose tissue
    4. Dsmooth muscle

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17. Question 17 · Easy

    Ligaments, which attach one bone to another, are made of

    1. Adense irregular connective tissue
    2. Badipose connective tissue
    3. Careolar connective tissue
    4. Ddense regular connective tissue

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18. Question 18 · Medium

    Assertion A: The frog has a long alimentary canal. Reason R: The frog is a carnivore. Choose the correct answer.

    1. ABoth A and R are correct but R is not the correct explanation of A
    2. BA is correct but R is not correct
    3. CBoth A and R are correct and R is the correct explanation of A
    4. DA is not correct but R is correct

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19. Question 19 · Medium

    Arrange these parts of the frog's brain from anterior to posterior. A. Medulla oblongata B. Optic lobes C. Olfactory lobes D. Cerebellum

    1. AB, C, D, A
    2. BC, B, A, D
    3. CC, D, B, A
    4. DC, B, D, A

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20. Question 20 · Medium

    During aestivation and hibernation, a frog exchanges gases through its

    1. Alungs
    2. Bgills
    3. Cbuccal cavity
    4. Dskin

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