細胞結構：练习题

Which organelle is responsible for the synthesis of lipids and the detoxification of drugs and poisons within a eukaryotic cell?

A scientist identifies a new unicellular organism. Which combination of features would confirm that this organism is a prokaryote and not a eukaryote?

Which of the following statements correctly distinguishes between the images produced by a Transmission Electron Microscope (TEM) and a Scanning Electron Microscope (SEM)?

Which of the following sequences correctly describes the interrelationship between organelles in the production and secretion of a protein, such as an enzyme?

The cytoskeleton is a complex network of protein fibers within eukaryotic cells. Which of the following is not a primary function of the cytoskeleton?

Explain why a transmission electron microscope (TEM) can achieve a significantly higher resolution than a standard light microscope, with reference to the type of radiation used.

Discuss the importance of the cytoskeleton in eukaryotic cells, explaining how it provides mechanical strength while simultaneously enabling the intracellular transport of vesicles.

Describe the functional relationship between the nucleolus and ribosomes in the context of protein synthesis within a eukaryotic cell.

A student is using a light microscope to observe a slide of plant cells. To measure the size of a cell, they must first calibrate the eyepiece graticule using a stage micrometer.

(a) Explain why the eyepiece graticule must be calibrated every time the objective lens is changed. (1)

(b) At a magnification of \(\times 400\), the student finds that 20 divisions of the eyepiece graticule correspond to 5 divisions of the stage micrometer. Each division on the stage micrometer is \(0.01\text{ mm}\).
Calculate the actual length of a cell that measures 12 eyepiece graticule divisions. Show your working. (2)

(c) The student then observes the same cells using a Transmission Electron Microscope (TEM). State one advantage of using a TEM over a light microscope for studying cell ultrastructure. (1)

The ultrastructure of cells varies significantly between different domains of life and different specialized tissues.

(a) Contrast the structure of the cell wall in a prokaryotic cell with that of a plant cell. (2)

(b) Describe two differences between the ribosomes found in a bacterial cell and those found in the cytoplasm of a human liver cell. (2)

(c) A researcher wishes to visualize the three-dimensional arrangement of cilia on the surface of a tracheal epithelial cell.
Evaluate whether a scanning electron microscope (SEM) or a transmission electron microscope (TEM) would be more appropriate for this task. (2)