Consider the following statements regarding unicellular organisms:
I. Unicellular organisms are capable of independent existence. II. They perform essential functions of life independently. III. Anything less than a complete cell structure ensures independent living. IV. Cell is the fundamental structural and functional unit of life.
Which statements are correct?
Unicellular organisms exist independently and perform all essential life processes. The cell is the fundamental structural and functional unit of life. Statement III is incorrect because anything less than a complete cell cannot ensure independent living.
Question 32 of 100
📘 CLASS XI
Consider statements regarding cell shapes in human tissues:
I. Red blood cells are round and biconcave. II. White blood cells are amoeboid. III. Columnar epithelial cells are long and narrow. IV. Nerve cells are short and unbranched.
Which of the following combinations is correct?
Red blood cells are biconcave discs, white blood cells are amoeboid, and columnar epithelial cells are long and narrow. Statement IV is incorrect because nerve cells are among the longest cells and are highly branched.
Question 33 of 100
📘 CLASS XI
Read the statements regarding bacterial cell shapes:
I. Bacillus shape is rod-like. II. Coccus shape is spherical. III. Vibrio shape is comma-shaped. IV. Spirillum shape is spiral.
Which statement combination is correct?
The four common bacterial shapes are bacillus (rod-shaped), coccus (spherical), vibrio (comma-shaped), and spirillum (spiral-shaped).
Question 34 of 100
📘 CLASS XI
Select the correct statements about prokaryotic cell envelope components:
I. Glycocalyx is the outermost layer. II. Cell wall forms the middle layer. III. Plasma membrane forms the innermost layer. IV. All three layers perform identical functions.
Which statements are correct?
The prokaryotic cell envelope consists of an outer glycocalyx, middle cell wall, and inner plasma membrane. Each layer performs distinct functions while together acting as a protective unit. Statement IV is incorrect because the three layers do not perform identical functions.
Question 35 of 100
📘 CLASS XI
Which of the following statements about chromatophores are correct?
I. Chromatophores are membranous extensions into cytoplasm in cyanobacteria. II. They contain pigments involved in photosynthesis. III. Chromatophores are found in all Gram-positive bacteria. IV. They are non-membranous protein granules.
Which statements are correct?
Chromatophores are membranous extensions present in photosynthetic prokaryotes such as cyanobacteria and contain photosynthetic pigments. Statements III and IV are incorrect because chromatophores are neither universal in Gram-positive bacteria nor non-membranous protein granules.
Question 36 of 100
📘 CLASS XI
Consider the following statements regarding bacterial flagellum structure:
I. Basal body is attached to the cell envelope. II. Hook connects the filament to the basal body. III. Filament is the longest part extending outside. IV. Flagella are non-filamentous rigid polysaccharide stalks.
Which statements are correct?
The bacterial flagellum consists of basal body, hook, and filament. The filament is the longest external portion. Statement IV is incorrect because bacterial flagella are filamentous proteinaceous structures, not rigid polysaccharide stalks.
Question 37 of 100
📘 CLASS XI
Read the statements regarding pili and fimbriae:
I. Pili are elongated tubular structures made of special protein. II. Fimbriae are small bristle-like fibers sprouting out of the cell. III. Pili help in cell motility across liquid media. IV. Fimbriae help attach bacteria to host tissues.
Which statement combination is correct?
Pili are elongated tubular protein structures, while fimbriae are short bristle-like fibers involved in attachment to surfaces and host tissues. Statement III is incorrect because pili do not function in bacterial motility.
Question 38 of 100
📘 CLASS XI
Consider the statements regarding inclusion bodies in bacteria:
I. Phosphate granules lie free in cytoplasm. II. Cyanophycean granules are membrane-bound storage sacs. III. Glycogen granules represent reserve material. IV. Gas vacuoles help blue-green algae float in water.
Which statements are correct?
Phosphate granules and glycogen granules are reserve materials present free in the cytoplasm. Gas vacuoles provide buoyancy in blue-green algae and photosynthetic bacteria. Statement II is incorrect because cyanophycean granules are not membrane-bound.
Question 39 of 100
📘 CLASS XI
Select the correct statements regarding eukaryotic plasma membrane lipids:
I. Phospholipids are arranged in a bilayer. II. Saturated hydrocarbon tails are nonpolar and protected from aqueous environment. III. Membrane lipid component also contains cholesterol. IV. Lipids form a rigid, non-fluid matrix preventing protein lateral movement.
Which statements are correct?
The plasma membrane consists of a phospholipid bilayer with hydrophobic tails facing inward. Cholesterol is also a membrane component. Statement IV is incorrect because membrane lipids are quasi-fluid, allowing lateral movement of proteins.
I. Classified into integral and peripheral proteins based on ease of extraction. II. Peripheral proteins lie on the surface of the membrane. III. Integral proteins are partially or totally buried in the membrane. IV. Integral proteins are easily washed off by water without detergent.
Which statements are correct?
Membrane proteins are classified as peripheral or integral based on their ease of extraction. Peripheral proteins occur on the membrane surface, whereas integral proteins are embedded within the lipid bilayer. Statement IV is incorrect because integral proteins require detergents or special treatments for extraction.
