Question

Wilting in plants occurs when
A) Phloem is blocked
B) Xylem is removed or blocked
C)Pith is removed
D)Few leaves are removed

Answer 1

Hint:Xylem transports water unidirectionally from roots to the tip of plants. Wilting is a result of excessive water loss.

Complete answer:
Wilting is the loss of rigidity of non-woody parts of plants. This occurs when the turgor pressure falls to zero especially in the non lignified plant cells, as a result of decreased water in the cells. Wilting also reduces water loss, as it makes the leaves expose less surface area during transportation.
The function of phloem is to carry food material and nutrients, sugar and amino acids. They are bidirectional. If for some reason the phloem gets blocked, the supply of food and nutrients will be affected.
The xylem vessels are primarily responsible for the transport of water molecules and minerals from the root to the tip of the plant. It is unidirectional. If the xylem is blocked, it might result in a loss of availability of water in the receiver cells and will ultimately reduce the turgor pressure gradually. This will lead to the loss of rigidity of cells and ultimately Wilting.
The pith is mainly the connecting link between all the parts of shoot and the root. If the pith was to be removed, the connection of the plant will break which will lead to death.
Removal of leaves won't make much difference in case the soil on which the plant is growing is fertile. New leaves will regrow in no time. But in case the plant is weak, it'll die. It will be a slow death since the leaves are a vital part of the plant as it is the centre of food production.

Hence the correct option is (B.) Xylem is removed or blocked.

Note:Removal of some plant parts can cause severe issues in its growth while with removal of other parts like leaves, the plant might survive for a couple of days. All the plant parts are important for a healthy growth of a plant. Apart from leaves, the roots, the collars and parts of stem can be affected due to disrupted organ functions and can result in a wilt.