Question

The following experiment was carried out at ILC laboratories to measure the effects of different nutrient solutions on bean root growth. Three nutrient solutions were made and are shown below.

Interpret the results for each solution.
In your answer for each, explain how the solution ranked in relation to the other two (in terms of growth and health of the plant); state the evidence that supports your answer; and explain why the plant grew the way it did.
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Answer 1

Based on the results of the experiment, it can be inferred that solution 1 was the most effective at promoting bean root growth and plant health, while solutions 2 and 3 were less effective.

Step-by-step explanation:

Solution 1 contained all required nutrients and resulted in root growth of 47mm and deep green leaf color. This indicates that the plant was healthy and thriving, as it was able to access all the nutrients it needed for growth and development. The deep green color of the leaves suggests that the plant was able to carry out photosynthesis effectively, which is crucial for plant health and growth. The evidence that supports this conclusion is the length of the roots and the color of the leaves, both of which indicate that the plant was healthy and thriving.

Solution 2, which lacked nitrogen, resulted in root growth of only 17mm and pale-green yellow leaves. This suggests that the plant was not receiving all the nutrients it needed for optimal growth and health. Nitrogen is an important nutrient for plant growth, particularly for the development of leaves, so the pale-green yellow color suggests that the plant was not able to carry out photosynthesis effectively. The evidence that supports this conclusion is the short length of the roots and the pale-green yellow color of the leaves.

Similarly, solution 3, which contained only distilled water, resulted in root growth of only 14mm and pale-green yellow leaves. This indicates that the plant was not receiving any of the nutrients it needed for growth and development. Without nutrients, the plant was not able to carry out essential processes such as photosynthesis, which is why the leaves were pale-green yellow in color. The evidence that supports this conclusion is the short length of the roots and the pale-green yellow color of the leaves.

Overall, the results of the experiment suggest that providing all required nutrients is essential for promoting bean root growth and plant health. Solutions that lack key nutrients, such as nitrogen, are less effective at promoting growth and can lead to pale-green yellow leaves and stunted root growth. Similarly, providing only distilled water is not sufficient for promoting plant growth and can lead to poor health and stunted growth.