Question 1: Define the term 'microscopy' and explain its importance in biological research.

Answer: Microscopy is the use of microscopes to observe objects that are too small to be seen with the naked eye. It is important in biological research because it allows scientists to study cell structures, microorganisms, and tissues in detail.

Question 2: Name two types of microscopes commonly used in biology and briefly describe their differences.

Answer: Light microscopes use visible light to magnify specimens and are suitable for viewing live or stained cells at lower magnifications. Electron microscopes use electron beams for much higher magnification and resolution, allowing detailed viewing of cell ultrastructure.

Question 3: Explain how the total magnification of a microscope is calculated.

Answer: Total magnification is calculated by multiplying the magnification power of the eyepiece lens by that of the objective lens. For example, if the eyepiece is ×10 and the objective is ×40, the total magnification is 10 × 40 = 400 times.

Question 4: What is the function of the coarse focus knob on a light microscope?

Answer: The coarse focus knob moves the stage or objective lens quickly to bring the specimen into general focus.

Question 1: A specimen appears 2 cm in the microscope's field of view when using a ×40 objective lens. What is the actual size of the specimen in micrometres? (Use the formula: Actual size = apparent size / magnification).

Answer: Actual size = (2 cm = 20,000 μm) / 40 = 500 μm

Question 2: If a cell measures 1.5 mm when viewed under a microscope with a total magnification of ×400, what is its actual size in micrometres?

Answer: Actual size = (1.5 mm = 1500 μm) / 400 = 3.75 μm

Question 1: Describe three safety precautions that should be followed when using a light microscope in a lab setting.

Answer: Ensure the microscope is on a stable surface, handle glass slides carefully to avoid cuts, and avoid touching the lens with fingers to prevent contamination.

Question 2: Design a simple experiment to observe onion cells using a light microscope. Include variables to be controlled and measured.

Answer: Prepare a thin slice of onion epidermis, stain with iodine solution, place on a slide, and cover with a cover slip. Control variables include the amount of stain used and the lighting. Measure the size of cells and record observations to compare cell structure before and after staining.

Question 1: A student observes a sample under a microscope and notes that the cells are elongated and have a prominent nucleus. What type of cell might these be, and how does microscopy aid in identifying cell features?

Answer: These could be plant or animal cells such as muscle or onion cells. Microscopy allows detailed observation of cell shape, nucleus position, and other structures, aiding in cell identification.

Question 2: Describe how increasing the magnification affects the field of view and the detail visible during microscopy.

Answer: Increasing magnification reduces the field of view, making a smaller area visible, but enhances the detail and resolution of small structures within the specimen.

Question 1: How has microscopy contributed to advancements in medical diagnostics?

Answer: Microscopy has enabled the detailed examination of blood, tissue, and pathogens, leading to accurate diagnosis of diseases, identification of microorganisms, and development of targeted treatments.

Question 2: Discuss one technological advancement in microscopy that has improved biological research and industry.

Answer: The development of electron microscopes has vastly increased resolution and magnification, allowing detailed observation of cellular ultrastructure, which benefits medical research, materials science, and nanotechnology.