Question

Mature Sieve tube elements are devoid of _____
A) Nucleus
B) Cytoplasm
C) Protein
D) Mitochondria

Answer 1

Hint: Sieve tube elements are an integral part of phloem that are placed one on the top of the other Along within a form of channel-like pattern that is utilized for conduction. The major function of the Sieve tube is the transport of carbohydrates, primarily sucrose, in the plant such as from the leaves to the fruits as well as to the roots.

Complete answer:
There are two classifications of sieve elements: sieve cells as well as sieve-tube members. The major objectives of sieve-tube members contain retaining cells along with transporting essential molecules with the help of companion cells. The sieve-tube members are living cells that are credible for transporting carbohydrates throughout the plant. Sieve tube units are correlated with companion cells, that are cells which incorporate sieve tubes to establish the sieve element-companion cell complex. At maturity sieve tubes are devoid of the nucleus but they are related with companion cells as in the function of mechanical support. Also, sieve tube cells contain none to a very small number of ribosomes. Instead of this the function of both of these kinds of sieve elements is the same, only sieve cells are found in gymnosperms, non-flowering vascular plants, while sieve-tube members are only found in angiosperms, flowering vascular plants.

So the correct answer to the question is Option A “Nucleus”.

Note:
Sieve elements are specialized cells which are vital for the function of, that is a highly organized tissue which transports organic compounds formulated during photosynthesis. Sieve elements are the main performing cells in the phloem.