Please explain. Thank you 11. You test a plant tissue in four concentrations of
ID: 200605 • Letter: P
Question
Please explain. Thank you
11. You test a plant tissue in four concentrations of sucrose using the Chardakov method: 0.2, 0.4, 0.6, and 0.8 molal. You decide to be very precise and attempt to quantify the results with a timer, and achieve the following result: Table 1. Results for a sample of plant tissue subjected to water potential analysis by the Chardakov method._ Direction of Rate of motion Treatment (cm minl) 5.0 3.0 1.5 0.5 motion 0.2 molal 0.4 molal 0.6 molal 0.8 molal Up Up Down A. 1pt. What, approximately, is the sap concentration of the tissue? B. 1 pt. Thinking about the analysis you performed for Part II of today's lab, how could you pin down a more exact estimate without going back and re-doing the experiment?Explanation / Answer
A. The sap concentration of the plant tissue is approximately 0.8 molal or slightly higher than it since there is still some movement of water in this concentration. According to the Chardakov method, the solution in which tissue is dipped, gains or looses water depending on the water potential of the tissue. If the density of a solution does not change (no net movement of water) then this solution has the same water potential as the tissues that were incubated in it. It is assumed that solute movement between tissue and solution is negligible. Density changes can be observed by watching whether a drop of the original solution floats or sinks in the test solution after tissue incubation
B. We could use two higher concentrations, where we should find that there is no net movement of water.