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Test your knowledge with these 36 questions
Assertion (A): Cell theory was unable to explain about continuity of cells.
Reason (R): Initial cell theory did not explain as to how new cells were formed.
Assertion (A): Rudolf Virchow was the pioneer scientist to modified Schleiden and Schwann's hypothesis.
Reason (R): Rudolf Virchow proposed about cell lineage.
Assertion (A): Cytoplasm is the main arena of cellular activities in both plants and animals.
Reason (R): Various chemical reactions occur in it to keep the cell in the living state.
Assertion (A): All the organelles of eukaryotic cells are surrounded by either single or double membrane.
Reason (R): In eukaryotic cell none of cell organelle can work and exist without membrane.
Assertion (A): Fluid nature of the membrane is not useful from the point of view of functions like cell growth.
Reason (R): Cell growth like function are dependent on cell division ability which is not associated with cell enlargement.
Assertion (A): Polar molecules cannot pass through non polar lipid bilayer.
Reason (R): Polar molecules require a carrier protein of the membrane to facilitate their transport across the membrane.
Assertion (A): Cell wall is not only a structural component but also show dynamic role for cell.
Reason (R): Cell wall helps in cell to cell interaction and provides barrier to undesirable macromolecules.
Assertion (A): Endoplasmic reticulum, golgibody, lysosome and vacuoles are collectively considered as endomembrane system.
Reason (R): Because all of these arise from same source that is nuclear envelope.
Assertion (A): Mitochondria, chloroplast and peroxisome are not involved in endomembrane system.
Reason (R): Their functions are not coordinated with constituents of endomembrane system.
Assertion (A): Smooth endoplasmic reticulum is frequently observed in protein secretory cells.
Reason (R): Lumen of smooth endoplasmic reticulum is the only storage site of secretory proteins.
Assertion (A): Mitochondria are the site of aerobic respiration.
Reason (R): In Mitochondria, complete breakdown of respiratory substrate takes place in presence of oxygen.
Assertion (A): Content of nucleolus is continuous with rest of the nucleoplasm.
Reason (R): Nucleolus is not covered with any kind of membrane.
Assertion (A): Larger and more numerous nucleoli are present in cells actively carrying out protein synthesis.
Reason (R): Nucleolus is the site for active ribosomal RNA synthesis.
Assertion (A): A single human cell has approximately two meter long thread of DNA distributed in each chromosome.
Reason (R): During different stages of cell division cells show organized nucleus in place of chromosome.
Assertion (A): Every chromosome essentially has a primary constriction or the centromere.
Reason (R): On sides of centromere disc shaped structure called kinetochore are present.
Assertion (A): Anton Von Leeuwenhoek first saw and described a live cell.
Reason (R): Robert Brown discovered nucleus.
Assertion (A): Cell theory did not explain as to how new cells were formed.
Reason (R): Rudolf Virchow explained that new cells are formed from pre existing cells.
Assertion (A): Cells vary greatly in their shape.
Reason (R): Shape may vary with the function the cell perform.
Assertion (A): All eukaryotic cells are not identical.
Reason (R): Centrioles are found in animal cells, absent in almost all plant cell.
Assertion (A): Primary wall is capable of growth.
Reason (R): It diminishes as cell matures.
Assertion (A): The number of mitochondria per cell is variable.
Reason (R): It depends upon physiological activities of the cells.
Assertion (A): Eukaryotic ribosome are 80s type.
Reason (R): 'S' indirectly measure of density and size.
Assertion (A): The most extensive metabolic diversity is observed in organism having incipient nucleus.
Reason (R): Nucleus in multicellular organism inhibits some metabolic diversity.
Assertion (A): Mitochondria, ER are largest organelle in an animal's cell.
Reason (R): Mitochondria, Chloroplast are semiautonomous cell organelles.
Assertion (A): Cell is the fundamental structural and functional unit of all living organisms.
Reason (R): Anything less than a complete structure of a cell does not ensure independent living.
Assertion (A): Like mitochondria, the chloroplasts are also double membrane bound. Of the two, the inner chloroplast membrane is relatively less permeable
Reason (R): Porins are present on inner membrane.
Reason (R): Because unicellular organisms can show independent existence and perform all metabolic activities.
Assertion (A): True chromatin is absent in prokaryotes.
Reason (R): Mitosis does not occur in prokaryotes.
Assertion (A): Ribosomes are known as RNP particles.
Reason (R): Ribosomes are made of rRNA and proteins.
Assertion (A): Lysosomes are called 'Suicidal bags'.
Reason (R): A large number of hydrolytic enzymes are present in lysosomes.
Assertion (A): Basal bodies are formed from centrioles.
Reason (R): Both basal bodies and centrioles have 9+2 structural organization.
Assertion (A): Microtubules are present in eukaryotic cells.
Reason (R): Centrioles, basal bodies, flagella, cilia, spindle fibres are formed by microtubules.
Assertion (A): Mitochondria is known as power house of cell.
Reason (R): ATP production takes place here.
Assertion (A): The cells of testes and ovaries have abundance of Smooth Endoplasmic Reticulum.
Reason (R): The cells of testes and ovaries secrete steroid hormones.
Assertion (A): The Golgi apparatus remains in close association with the endoplasmic reticulum.
Reason (R): The cis and the trans faces of the organelle are entirely different, but interconnected.
Assertion (A): In eukaryotic cells, there is an extensive compartmentalisation of cytoplasm.
Reason (R): Eukaryotic cells are characterised by the presence of membrane bound organelles.