Question

Which protozoan has a unique appearance, with a blue halo, when viewed using ultraviolet fluorescence microscopy? a. Giardia lamblia b. Cryptosporidium hominis c. Cyclospora cayetanesis d. Entamoeba histolytica

Short answer

c. Cyclospora cayetanesis

Step-by-step solution

- Understanding the Question

The question asks which protozoan exhibits a unique appearance, specifically a blue halo, when observed using ultraviolet fluorescence microscopy.

- Review Known Characteristics

Identify and review the key characteristics of each protozoan provided in the options to determine which one is associated with a blue halo under ultraviolet fluorescence microscopy.

- Check Evidence from Scientific Literature

According to scientific literature and microbiological studies, it is known that Cyclospora cayetanesis exhibits a distinctive blue halo when observed under ultraviolet fluorescence microscopy.

- Confirm the Answer

Based on the collected information and evidence, confirm that the protozoan with the unique appearance of a blue halo under ultraviolet fluorescence microscopy is Cyclospora cayetanesis.

Key concepts

Cyclospora cayetanesis identification

Cyclospora cayetanesis is a protozoan parasite that can cause a gastrointestinal illness called cyclosporiasis in humans. This organism is primarily transmitted through contaminated food and water. Identifying Cyclospora cayetanesis is crucial in preventing and managing outbreaks of this disease. When viewed under ultraviolet fluorescence microscopy, Cyclospora cayetanesis displays a unique and distinct appearance with a blue halo around it. This characteristic fluorescence makes it easier for microbiologists and laboratory technicians to isolate and identify it from other protozoans. This blue halo phenomenon aids in differentiating it from other similarly structured organisms.

Fluorescent Microscopy Techniques

Fluorescent microscopy is a powerful technique that uses high-intensity light to excite the fluorescent molecules in a sample. These molecules then emit light at a different wavelength, which is captured to create an image.
This technique is especially useful in microbiology for identifying microorganisms, such as protozoans, by their unique fluorescent properties. Several steps are typically involved in fluorescent microscopy:

• Preparation of the sample, often involving specific staining methods.
• Exciting the sample with ultraviolet light.
• Capturing the emitted light to form an image.

In the context of identifying Cyclospora cayetanesis, ultraviolet fluorescence microscopy is used to detect the distinctive blue halo around the organism, simplifying its identification amidst other protozoans.

Protozoan Characteristics

Protozoans are a diverse group of single-celled eukaryotic organisms that are capable of various forms of movement and can be free-living or parasitic. Their characteristics include:

• Different shapes and sizes, often measuring between 10-50 micrometers.
• Mobility structures like cilia, flagella, or pseudopodia.
• Complex life cycles, often involving multiple stages and hosts.
• Reproduction can be asexual or sexual.

Cyclospora cayetanesis, for instance, is notable for its oocysts that can be identified by their size, shape, and unique fluorescence under ultraviolet light. Recognizing the key features and life cycles of various protozoans is essential for diagnosing and treating infections effectively.