Which of the following is a factor that can affect the richness of a microbiological growth medium?

• A. The concentration of nutrients such as glucose and amino acids
• B. The shape of the petri dish
• C. The humidity of the laboratory air
• D. The color of the medium

Answer: (A)

Verified step by step guidance

1. Understand the term 'richness' in the context of a microbiological growth medium. Richness refers to the variety and abundance of nutrients available in the medium that support microbial growth.
2. Identify factors that directly influence the nutrient content of the medium. These include the concentration of essential nutrients such as glucose, amino acids, vitamins, and minerals.
3. Evaluate the options given: the shape of the petri dish, humidity of the laboratory air, and the color of the medium do not directly affect the nutrient composition or richness of the medium.
4. Recognize that the concentration of nutrients like glucose and amino acids directly impacts the richness because these compounds serve as energy sources and building blocks for microbial cells.
5. Conclude that among the options, the concentration of nutrients such as glucose and amino acids is the factor that affects the richness of a microbiological growth medium.