Quiz

QUIZ

1. Which type of microbe does not belong to any of the domains of life?

a. Bacterium b. Helminth c. Parasite d. Virus

Answer: d. Viruses do not belong to any of the domains of life, mostly because they are completely acellular. Some researchers do not believe that viruses are actually living things.

2. Which type of bacterial species is curved in shape?

a. Vibrio b. Bacillus c. Coccus d. Spirochete

Answer: a. The Vibrio organism is considered a curved-shaped bacterium.

3. What pathogen in humans is always multicellular?

a. Fungi b. Protozoa c. Helminths d. Bacteria

Answer: c. Helminths are always multicellular and are rarely microscopic; however, their eggs and larvae are generally microscopic in nature.

4. Which type of pathogen is most likely to infect a bacterium?

a. Fungi b. Virus c. Archaea d. Protozoa

Answer: b. Because bacteria are so small themselves, only viruses have the ability to infect them. Viruses that infect bacteria are called bacteriophages.

5. What is the advantage of using darkfield microscopy to look at an image under the microscope?

a. The resolution is greater b. The image can be living and unstained c. It can see viral particles d. The magnification available is greater

Answer: b. The main advantage of darkfield microscopy is that the image seen can be living and unstained so that the characteristics of a living organism can be understood.

6. Which type of microscopy will require staining in order to see the specimen?

a. Electron microscopy b. Phase contrast microscopy c. Darkfield microscopy d. Differential interference contrast microscopy

Answer: a. An electron microscope specimen requires a stain but none of the others need staining and can be used to visualize a living specimen.

7. What microscopy technique delivers the highest magnification possible in the field of microscopy?

a. Scanning electron microscopy b. Scanning probe microscopy c. Transmission electron microscopy d. Two-photon microscopy

Answer: b. Scanning probe microscopy offers the greatest magnification possible in a microscope. It does not use light or electron waves so it can see things at up to 100 million times magnification.

8. What chemical is least likely to be used to chemically fix a specimen when preparing a microscope slide?

a. Acetic acid b. Methanol c. Sodium hydroxide d. Formaldehyde

Answer: c. Each of these can be used to chemically fix a specimen; however, sodium hydroxide is a strong base that would more likely destroy the specimen.

9. Which type of staining technique makes use of India ink to negatively stain the background but nothing to stain the items of interest?

a. Gram staining b. Endospore staining c. Capsule staining d. Acid-fast staining

Answer: c. Capsules do not take up any stain so that a negative stain like India ink is used to highlight the background.

10. What stain is not used with electron microscopy?

a. Gold b. Uranyl acetate c. Osmium tetroxide d. Pararosaniline

Answer: d. Each of these is used in electron microscopy, except for pararosaniline, which is used for flagella staining.