Very small organisms, like paramecia or protozoa, moving around in water are best observed using which type of microscope?

• A. Scanning tunneling microscope
• B. Light microscope
• C. Atomic force microscope
• D. Electron microscope

Answer: (B)

Verified step by step guidance

1. Step 1: Understand the size and nature of the organisms mentioned. Paramecia and protozoa are microscopic, single-celled organisms that are generally visible under light microscopes due to their size, which ranges from about 10 to 300 micrometers.
2. Step 2: Review the types of microscopes listed and their typical uses: the scanning tunneling microscope and atomic force microscope are used for imaging surfaces at the atomic level, electron microscopes provide very high magnification for ultrastructural details, and light microscopes are commonly used for viewing living cells and microorganisms in water.
3. Step 3: Recognize that light microscopes use visible light and lenses to magnify specimens, making them suitable for observing live, moving microorganisms like paramecia in water without extensive sample preparation.
4. Step 4: Contrast this with electron microscopes, which require samples to be fixed, dehydrated, and placed in a vacuum, making them unsuitable for observing live movement in water.
5. Step 5: Conclude that the best microscope for observing very small, moving organisms like paramecia in water is the light microscope, as it balances magnification, resolution, and the ability to view live specimens.