Which of the following cellular structures can typically be observed using light microscopy, but require electron microscopy for detailed visualization?

• A. Ribosomes and endoplasmic reticulum
• B. Mitochondria and ribosomes
• C. Nucleus and cell wall
• D. Plasma membrane and cytoplasm

Answer: (A)

Verified step by step guidance

1. Step 1: Understand the resolution limits of light microscopy and electron microscopy. Light microscopy typically allows visualization of structures larger than about 200 nanometers, while electron microscopy can resolve much smaller structures down to a few nanometers.
2. Step 2: Identify the size and visibility of each cellular structure under light microscopy. For example, the nucleus and cell wall are large enough to be seen clearly with light microscopy, whereas ribosomes are too small to be resolved by light microscopy.
3. Step 3: Recognize that mitochondria are generally visible under light microscopy as distinct organelles, but their internal details require electron microscopy for detailed visualization.
4. Step 4: Note that the endoplasmic reticulum (ER) is a network of membranes that is often too fine to be seen clearly with light microscopy, so electron microscopy is needed to observe its detailed structure.
5. Step 5: Conclude that structures like ribosomes and the endoplasmic reticulum require electron microscopy for detailed visualization, even though some larger organelles like the nucleus and mitochondria can be seen with light microscopy.