Chapter 1. Nitrogen and Iron Deficiencies

Which is a reason for using liquid plant growth medium in the experiments discussed in the animation?

Older leaves turn yellow while new leaves are green because

A man observes that the tomato plants in his garden were healthy and green until they grew large enough to begin producing fruit. At that time, the youngest leaves began developing with a yellow color, although otherwise the plants appeared to be healthy. Of the following statements, which is most likely to be the reason for this change?

Suppose an experiment was conducted over a 20-week period using four groups of the same plant as shown in the table. Plus and minus symbols are used to indicate the addition or omission of nitrogen (N) and iron (Fe) to or from the soil. In which experimental group(s) would you expect to observe movement of both nitrogen and iron in the vascular tissue of the plant at 20 weeks?