YEPD Agar (Yeast Extract Peptone Dextrose) MCQs Mock Test for Lab Professionals & Medical Students
Master the fundamentals of YEPD Agar (Yeast Extract Peptone Dextrose)—a cornerstone medium in yeast and fungal cultivation. This article provides a targeted MCQ mock test (30 questions) for lab professionals and medical students, framed by concise educational content. Test your knowledge of YEPD’s composition, applications, preparation, and troubleshooting, then reinforce learning with post-test key takeaways.
YEPD Agar Fundamentals
What is YEPD Agar?
YEPD Agar is a complex, nutrient-rich medium used primarily for cultivating Saccharomyces cerevisiae and other fungi/yeasts. Its versatility in research, industrial microbiology (e.g., brewing, biotechnology), and diagnostics makes it essential knowledge.
Key Components & Functions:
- Yeast Extract: Supplies B-vitamins, nucleotides, and amino acids.
- Peptone: Provides organic nitrogen and carbon.
- Dextrose (Glucose): Fermentable carbohydrate energy source.
- Agar: Solidifying agent (typical concentration: 2%).
Common Applications:
- Yeast culture maintenance and propagation.
- Genetic transformation studies.
- Antimicrobial susceptibility testing for fungi.
- Fermentation research (e.g., ethanol production).
Preparation Protocol Highlights:
- Dissolve 10g yeast extract, 20g peptone, and 20g dextrose in 1L distilled water.
- Add 20g agar for solid medium.
- Autoclave at 121°C for 15 minutes.
- Pour plates at 45–50°C; store inverted at 4°C.
Critical Considerations:
- pH: Typically 6.5 (±0.2). Adjust with NaOH/HCl if needed.
- Contamination Risks: Avoid overheating dextrose to prevent caramelization.
- Alternatives: YPDA (YEPD + adenine) for adenine-auxotroph yeast strains.
Key Takeaways & Resources
Review Your Performance:
- Score 25+: Strong grasp of YEPD principles. Focus next on advanced applications (e.g., gene editing in yeast).
- Score 15–24: Solid foundation. Revise preparation protocols and contamination control.
- Score <15: Revisit core concepts below.
Must-Know Concepts Reinforced:
- Selectivity: YEPD is non-selective—supports broad yeast/fungal growth. For selectivity, additives like antibiotics (e.g., G418) are used.
- Troubleshooting:
- Crystallization? → Re-autoclave agar separately.
- Poor growth? → Verify dextrose integrity (avoid moisture degradation).
- Industrial Relevance: Used in biofuel production and recombinant protein synthesis (e.g., insulin).
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The content on LabTestsGuide.com is for informational and educational purposes only. We do not guarantee the accuracy, completeness, or timeliness of the information provided. Always consult qualified healthcare professionals for medical advice, diagnosis, or treatment. LabTestsGuide.com is not liable for any decisions made based on the information on this site.







