Final answer:
It's impossible to assess if there's a significant difference in the mean iron contents in fruits before and after manure application from the incomplete data provided; full data and proper statistical analysis would be needed. Farm yard manure may affect soil nutrient levels. The use of metallic iron in food fortification exemplifies the practical application of iron in human nutrition.
Step-by-step explanation:
Whether there is a significant difference between the mean iron contents in fruits before and after applying farm yard manure cannot be determined from the data as presented. The values for fruit no. 1 before manure application and fruit no. 8 after application suggest there could be a change; however, most of the data points are missing (?), making it impossible to calculate and compare the mean values accurately. To assess any significant difference statistically, a complete dataset for both conditions would be required followed by statistical analysis such as a paired t-test assuming the data meets the necessary assumptions (such as normality).
Farm yard manure is known to affect soil nutrient levels including iron content which could influence the iron uptake in fruits. Iron is essential for plant growth and is mostly absorbed as either the ferrous (Fe²⁺) or ferric (Fe³⁺) ion. Fortified foods with iron, and iron absorption by heterotrophs and plants are important considerations in agriculture and nutrition.
In the context of general iron consumption, the use of "reduced iron" or metallic iron as a supplement in food like bread and breakfast cereals is an example of iron fortification. The body oxidizes this metallic iron to the ferrous state for absorption.