Question

Scientists are testing the impact of soil on the growth of a plant. they add the plant to soil that has been sterilized (removed of all microbes), and the plant fails to grow. what might be one cause of this finding?

a) a lack of nutrients in the soil
b) a lack of microbes that will fix nitrogen
c) a lack of microbes to produce oxygen
d) a lack of microbes that will fix nitrogen

Answer 1

The plant likely failed to grow in sterilized soil due to the absence of nitrogen-fixing microbes, which are crucial for converting atmospheric nitrogen into forms that plants can use, impacting the availability of essential nutrients.

Therefore the correct answer is option b) a lack of microbes that will fix nitrogen

Step-by-step explanation:

One cause of the finding that a plant fails to grow in sterilized soil, which has been removed of all microbes, could be b) a lack of microbes that will fix nitrogen. Soil microbes, including bacteria, play an essential role in the nitrogen cycle by converting atmospheric nitrogen into forms usable by plants. Soil ecosystems provide various ecosystem services, including nutrient cycling, which is essential for plant growth.

Without the presence of nitrogen-fixing microbes, plants are unable to obtain the necessary nitrogen needed to synthesize proteins and grow. In addition, such microbes contribute to the breakdown of organic matter into nutrient compounds required for crop success. Therefore, the absence of soil microbes can greatly impact the availability of critical nutrients, like nitrogen, leading to stunted plant growth or, in some cases, failure to grow altogether.