Cell: The Unit of Life Mock Test – Class 11 Biology

1. A mutation disables the carrier used by polar solute P. The plasma membrane remains intact, neutral solute Q still diffuses normally, and an unrelated ATP-dependent ion pump continues to function. The immediate prediction is:

2. Equal samples of intact cells are gently separated into a cytoplasmic fraction and a fraction containing mainly empty boundary material. Numerous soluble reaction activities are detected in the cytoplasmic fraction, while the boundary fraction shows far fewer. The strongest supported inference is that:

3. Four preparations are maintained under suitable conditions: an isolated nucleus, isolated mitochondria, free ribosomes and intact unicellular organisms. Only the intact cells grow and reproduce over successive generations. The strongest inference is that:

4. Consider the following statements about Golgi function.
I. Proteins synthesised on RER-associated ribosomes may be modified in Golgi cisternae.
II. The Golgi apparatus is an important site for glycoprotein and glycolipid formation.
III. Translation of messenger RNA occurs mainly inside Golgi cisternae.
IV. Modified products may be packaged before leaving the trans face.

5. A cell image shows a membrane-bound compartment P. Inside P are several thread-like structures Q, and each Q contains hereditary material R. The most accurate identification is:

6. Animal cells are treated with a substance that prevents centrioles from contributing to spindle organisation but leaves chromosomal DNA replication and mitochondrial ATP production intact. The most direct expected defect is:

7. Contractile-vacuole activity is selectively stopped in a freshwater Amoeba, while its plasma membrane and food vacuoles remain functional. The most immediate expected effect is:

8. One chromosome is removed from the nucleus of a typical eukaryotic cell without disrupting the nuclear envelope or the remaining chromosomes. Which conclusion follows from the part–whole relation?

9. Examine the following cellular records.

The record requiring correction is:

10. The grouping that applies membrane enclosure consistently is:

11. A smooth mitochondrial inner membrane would have an area of relative units. Folding into cristae raises its total area to relative units. The folded membrane has:

12. Consider the following statements about nuclear number in eukaryotic cells.
I. One nucleus per cell is common but not universal.
II. Mature mammalian erythrocytes may remain living despite lacking a nucleus.
III. Mature vascular-plant sieve-tube cells may also lack nuclei.
IV. Every living eukaryotic cell must contain one nucleus at every stage of its existence.

13. One bacterial strain grows normally without an antibiotic but is resistant when the antibiotic is added. After a small circular DNA molecule is experimentally eliminated, growth without the antibiotic remains normal, while resistance is lost. The strongest inference is:

14. Suppose the bacterial wall is selectively weakened while the plasma membrane retains normal selective permeability. Under conditions that place mechanical stress on the cell, the expected result is:

15. Consider the following statements about modern cell theory.
I. Living organisms are composed of cells and cellular products.
II. The cell is the basic structural and functional unit of life.
III. New cells arise from pre-existing cells.
IV. New cells normally originate spontaneously from non-cellular material.

16. A graph plots relative activity of an isolated lysosomal hydrolase on the vertical axis against pH on the horizontal axis. Activity is highest in the acidic region, declines near neutral pH and remains low in the alkaline region. The graph supports the conclusion that:

17. Use the arrangements described below. Cell P contains DNA in an unenclosed region and lacks membrane-bound organelles. Cell Q contains chromosomes inside a nuclear envelope and also has mitochondria and endoplasmic reticulum. The cells are respectively:

18. An unknown ribosome is isolated from inside a membrane-bound organelle of a eukaryotic cell. It belongs to the class. The organelle could most reasonably be:

19. Regions P and Q of one ER network produce the following records.

The correct interpretation is:

20. In two bacteria, an outer coating lies outside the cell wall, which in turn lies outside the plasma membrane. The coating is loose and unorganised in P but thick and tough in Q. The correct interpretation is:

21. Two bacterial membrane extensions are compared.

Which conclusion best explains the different effects?

22. A non-dividing nucleus contains a diffuse thread-like material P, one or more dense spherical regions Q and a surrounding internal matrix R. P, Q and R are respectively:

23. A large central compartment occupies most of a plant cell. Structure P forms its boundary, while region Q contains water, ions, pigments and other dissolved materials. P and Q are respectively:

24. A prokaryotic glycogen granule and a typical plant-cell vacuole can both contain stored material. The feature that most directly separates them is that:

25. Assertion: Lysosomes and vacuoles are both included in the endomembrane system.
Reason: Lysosomal hydrolytic enzymes generally function optimally at acidic pH.

26. Consider the following statements about mitochondria.
I. Their number in a cell may vary with the cell's physiological activity.
II. They are commonly sausage-shaped or cylindrical.
III. Their diameter generally ranges from , with an average near .
IV. Their usual length ranges from .

27. From observations of many plant materials in , Matthias Schleiden concluded that:

28. Three colourless or coloured plastids are isolated from plant tissues.

P, Q and R are respectively:

29. Two bacterial samples are subjected to Gram staining under identical conditions. Sample P retains the stain, whereas sample Q does not. They should be placed respectively in:

30. Using the representative dimensions for Mycoplasma and for a human erythrocyte, the erythrocyte diameter is approximately:

31. A mutation removes the two central microtubules from a eukaryotic cilium but leaves all nine peripheral doublets present. The altered axonemal pattern is:

32. An organelle isolated from a leaf mesophyll cell is discoid, measures , contains chlorophyll and is enclosed by two membranes. It is most likely:

33. Four membrane movements are listed below.

The most accurate evaluation is:

34. A drug disrupts much of the cytoskeletal network while leaving the plasma membrane, ribosomes and mitochondria initially intact. Which combination of effects is most likely?

35. Arrange the chromosome types from a centromere in the middle toward a centromere at the terminal end.
P. Acrocentric
Q. Telocentric
R. Metacentric
S. Submetacentric

36. A cell has a small central body, numerous short branches and one exceptionally long process extending toward distant cells. Its form is most consistent with:

37. Within a chromosome, primary constriction P holds the chromatids together. Farther along one arm, a constant non-staining constriction Q separates a small terminal segment R. Q and R are respectively:

38. Match each observed disturbance in Column I with the mesosome-associated relation in Column II. A Column II entry is used once.

39. Four unknown cells are compared.

The internally consistent eukaryotic record is:

40. Examine the following plastid-storage records.

The record requiring correction is:

41. In a bacterial flagellum, the longest part projecting from the cell surface is the ______, which is connected through a hook to the basal body.

42. Assertion: Schleiden's conclusion connected the diversity of plant cells with the cellular organisation of plant tissues.
Reason: Repeated observations of many plants supported a generalisation that plant bodies are composed of cells.

43. A membrane arrangement contains protein P attached only to the cytoplasmic surface, protein Q extending across the entire bilayer and protein R embedded within one leaflet without crossing it completely. Their classifications are:

44. A membrane protein uses ATP to move selected ions from a region of lower concentration to a region of higher concentration. The pump is an example of this category. The process is:

45. An animal endocrine cell produces a large quantity of a lipid-like steroidal hormone but secretes relatively little protein. Its cytoplasm is expected to contain:

46. Evaluate the following statements using the representative scale values.
I. Viruses may range from to .
II. PPLO may have a value near .
III. Overlapping dimensions make size alone insufficient for deciding cellular status.
IV. Viruses should be classified as the smallest cells.

47. Starting in the cytoplasm and moving directly into the nucleoplasm across an intact region of nuclear envelope that is not a pore, which sequence is correct?

48. An unknown cell possesses a membrane-bound nucleus, mitochondria, ER and Golgi apparatus. A rigid wall lies outside its plasma membrane, but plastids are absent. Which interpretation is most justified?

49. A stack of flattened cisternae lies near the nucleus. Surface P is convex and receives vesicles arriving from the ER, while surface Q is concave and releases processed material. P and Q are:

50. In a multicellular organism, one specialised cell group loses its assigned essential function, and no other cell group can compensate. The most likely consequence is that: