Cell-the unit of life practice · Mixed difficulty

Option C is correct because plasmodesmata are channels connecting adjacent plant cells, allowing dye to pass through.

Option B (Secondary active transport) is correct because the cell already has a higher concentration of K+, and more K+ is entering, indicating transport against the concentration gradient, coupled with another ion's movement.

Option C (Mitochondria and bacterial cell) is correct because both mitochondria (in eukaryotes) and bacterial cells contain their own ribosomes for protein synthesis.

Option B (Tails of membrane lipids are hydrophilic) is correct because the tails of membrane lipids are hydrophobic, not hydrophilic.

Option D (All of the above) is correct because prokaryotic cells lack internal compartments and a nucleus, and their ribosomes are 70S.

Option A (Plasma membrane) is correct because the plasma membrane is characterized by having a lipid bilayer structure.

Option B (Lysosome) is correct because lysosomes are single membrane-bound organelles responsible for intracellular digestion.

Option D is correct because prokaryotic cells lack membrane-bound organelles like endoplasmic reticulum, Golgi bodies, and spindle fibers.

Option D is correct because the plant cell wall provides protection, facilitates cell-cell interaction, and acts as a barrier.

Option C (Chromosomes and chromatin) is correct because DNA in eukaryotic cells is organized as both chromosomes during cell division and chromatin during interphase.

Option C (The outermost glycocalyx is followed by cell wall and plasma membrane) is correct because this is the correct order of the layers in a bacterial cell envelope.

Option C (Occurs from lower to higher concentration) is correct because the sodium-potassium pump moves ions against their concentration gradients, requiring energy.

Option D (Janus green) is correct because Janus green is a vital stain specifically used to visualize mitochondria in living cells.

Option B (Sub-metacentric chromosome) is correct because sub-metacentric chromosomes have centromeres slightly away from the middle, resulting in L-shaped appearance during anaphase.

Cell in the interphase is the correct answer because the nucleus is most visible and accessible for study during interphase when the chromosomes are not condensed.

Option A is correct because plasmodesmata are cytoplasmic channels that directly connect adjacent plant cells, facilitating transport.

Option A is correct because cystoliths, which are crystals found in some plant cells, are composed of calcium carbonate.

Option A (Pilli – involved in locomotion) is correct because pili are primarily involved in attachment and conjugation, not locomotion. Flagella are the primary structures for locomotion in bacteria.

Option D (Internal membrane system that may become extensive and complex in photosynthetic bacteria) is correct because chromatophores are internal membrane systems in photosynthetic bacteria that contain pigments for photosynthesis.

Option C is correct because while every cell behaves as a compartment, the reason is not because an organelle has a particular structure and function. The compartmentalization is due to the cell membrane.

Option A (Nuclear sap) is correct because karyolymph is another term for nuclear sap, the fluid-filled substance within the nucleus.

Option A (Interior of the Plasma membrane) is correct because the hydrophobic tails of phospholipids are oriented inward, away from the aqueous environment.

Option D (Gap junction) is correct because gap junctions are specialized cell junctions that allow direct communication between the cytoplasm of adjacent cells.

Option D (C and D) is correct because Golgi complex and Lysosomes do not contain DNA, while Mitochondria and Chloroplasts do.

Option D (All of these) is correct because secondary metabolites can be found in plant, fungal, and microbial cells.

Their copy number varies from individual to individual but not from chromosome to chromosome in an individual is incorrect because the copy number of minisatellites (VNTRs) can vary not only between individuals but also between homologous chromosomes within an individual.

Option D (1 and 2) is correct because the 9+2 arrangement of microtubules is characteristic of both cilia and flagella.

Option A is wrong because lysosomes are single-membraned vesicles, not double-membraned.

Option A (Mitochondria) is correct because mitochondria possess their own DNA, which is circular and similar to that found in prokaryotic cells.

Option A (Acid hydrolases) is correct because lysosomes, known as suicidal bags, contain acid hydrolases which are enzymes that break down cellular waste and debris.