Question

Ringing experiment is to show
A. Translocation of food
B. Passive absorption
C. Stomatal opening and closing
D. None of the above

Answer 1

Hint:- Pteridophytes, gymnosperms, and angiosperms are the vascular plants. These plants have vascular tissues involved in the transport of substances within the plant body. Xylem and phloem are the two types of vascular tissues.

Complete step-by-step solution:-
Vascular plants are complex multicellular organisms. Plant roots absorb water from the soil passively while most of the minerals are absorbed by active transport. Xylem transports water and minerals absorbed by roots to the shoot. Stomata are the tiny pores present mainly on the surface of leaves. The opening and closing of the stomatal pore are regulated by guard cells.
Vascular plants depend on vascular tissues for the transport of substances. For instance, leaves synthesize organic sugars in plants by the process of photosynthesis. The growing plant parts obtain organic sugars from the leaves. This movement of substances within the plant body is called translocation and occurs through the phloem.
In the ringing experiment, a complete ring of bark is removed from a tree trunk or stem. It is also called girdling. Ringing causes swelling of the tissue that is present just above the ringing part. The tissues present below the ring droop. The swollen tissue shows an accumulation of liquid rich in sugars and organic solutes.
Since phloem is present just below the bark, removal of bark also removes phloem. Removal of phloem tissue disrupts the downward translocation of organic substances. Therefore, the tissues present below the ring wither. Therefore, the ringing experiment shows the role of phloem tissue in the translocation of food.
So, the correct answer is option A. Translocation of food

Note:- Xylem tissue is present deep in the stem. Therefore, xylem is not damaged by ringing. So, the transport of water and minerals is not affected by ringing.