Approximately how many times smaller is a typical virus compared to a typical bacterium?

• A. 1000 times
• B. 2 times
• C. 10 times
• D. 100 times

Answer: (D)

Verified step by step guidance

1. Step 1: Understand the typical size ranges of viruses and bacteria. Viruses generally range from about 20 to 300 nanometers (nm) in diameter, while typical bacteria range from about 1 to 10 micrometers (µm) in length. Note that 1 micrometer equals 1000 nanometers.
2. Step 2: Convert the sizes to the same unit for easy comparison. For example, convert bacterial size from micrometers to nanometers by multiplying by 1000. So, a typical bacterium of 1 µm is 1000 nm.
3. Step 3: Choose representative average sizes for comparison. For instance, take a typical virus size as 100 nm and a typical bacterium size as 1 µm (1000 nm).
4. Step 4: Calculate the size ratio by dividing the bacterial size by the viral size: \(\frac{1000\ \text{nm}}{100\ \text{nm}}\).
5. Step 5: Interpret the ratio to determine how many times smaller the virus is compared to the bacterium. This ratio gives the factor by which the virus is smaller.