Question

Comment upon the following based on Absorbtion by roots and ascent of sap.
1. Large quantity of salts in pickles, and sugar in jams and jellies is added.
2. The leavesof touch-me-not plant droop down on slight touching.

Answer 1

Dear student,

Ans1. This is done in order to preserve the pickles and jams. By adding a lot of salts and sugar the solution is made hypertonic. The salt and the sugar absorbs the excess water, which is required by the bacteria and fungi to grow, and thus the pickles and jams are preserved.

Ans2. ​It occurs due to turgor pressure difference between the upper and lower halves of the base of petiole.Transfer of water from lower cells to upper cells occurs due to loss of water and therefore upper half cells of petiole become turgid . Thus, the entire leaf droops down when slightly touched.

Regards.