Chapter 2
Cellular Organelles
Exercises
1. The Fluid Mosaic Model has been proposed by
(a) Robert Brown
(b) Schleiden and Schwann
(c) Robert Virchow
(d) Singer and Nicolson
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2. Ribosomes are composed of
(a) only rRNA
(b) rRNA and proteins
(c) rRNA, proteins and DNA
(d) lipids, proteins and DNA
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3. Tonoplast is
(a) a membrane covering the cell wall in plant cells
(b) the inner membrane of the mitochondria
(c) a membrane covering the vacuoles
(d) a membrane covering the plastids
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4. Describe the various mechanisms of transport across plasma membrane with the help of labelled diagrams.
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5. Match the following
6. What is the significance of the ratio of protein and lipids in membranes? How does varying the concentration of lipids in a membrane affect its function?
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7. State the importance of cell wall in prokaryotic cells.
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8. A eukaryotic cell contains organelles which may be bound by a single membrane; double-membrane or non-membrane bound organelles. Classify the various eukaryotic organelles into these three types.
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9. Mention the different types of vacuoles.
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10. Peroxisomes share similarities as well as differences with mitochondria and chloroplast. Comment.
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11. What are glyoxysomes? Where are these present? Mention their functions.
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12. Cell is the structural and functional unit of life. Justify the statement.
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13. Distinguish between
(a) cilia and flagella
(b) primary and secondary cell wall
(c) lysosomes and vacuoles
(d) microtubules and actin filaments
(e) active and passive transport
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