A soybean farmer finds that the older leaves of his plant are turning yellow following a long period of wet weather. Suggest a reason why.

Do your result s imply t hat the uptake of water by radish seeds is mainly a physical process or a chemical (metabolic) process?

What is the average $Q_{10} ?$

Using the data for 35 degree C and 25 degree C , calculate $Q_{10}$ for water uptake by radish seeds. Repeat the calculation using the data for 25 degree C and 15 degree C and the data for 15 degree C and 5 degree C.

How do soil bacteria and mycorrhizae contribute to plant nutrition?

Is xylem sap usually pulled or pushed up the plant?

If an element increases the growth rate of a plant, can it be defined as an essential element?

If you buy cut flowers, why might the florist recommend cutting the stems underwater and then transferring the flowers to a vase while the cut ends are still wet?

What architectural features influence self-shading?

How would having fewer aquaporin channels affect a plant cell's ability to adjust to new osmotic conditions?

Which of the following is an adaptation that enhances the uptake of water and minerals by roots?

(A) mycorrhizae

(B) cavitation

(C) active uptake by vessel elements

(D) rhythmic contractions by cortical cells

Suppose an Arabidopsis mutant lacking functional aquaporin proteins has a root mass three times greater than that of wild-type plants. Suggest an explanation.

Why can xylem transport water and minerals using dead cells, whereas phloem requires living cells?

(a) Which of the three community locations was least like the other two?

(b) Rank the three variables (community location, developmental stage of roots, and soil type) in terms of how strongly they affect the "species" composition of the bacterial communities.