AP BIOLOGY

Detailed explanation-1: -sieve element, in vascular plants, elongated living cells of the phloem, the nuclei of which have fragmented and disappeared and the transverse end walls of which are pierced by sievelike groups of pores (sieve plates). They are the conduits of food (mostly sugar) transport from the leaves to the rest of the plant.

Detailed explanation-2: -Sieve elements are thin-walled cells that are alive at maturity, although the protoplast is greatly changed, and they generally lack nuclei. Sieve elements are elongated and function as the basic photosynthate-conducting cell type in the phloem of vascular plants.

Detailed explanation-3: -Answer: Sieve tubes transports food manufactured in the leaves to the other parts of the plant.

Detailed explanation-4: -The sugar in the form of sucrose is moved into the companion cells and then into the living phloem sieve tube cells by active transport.

Detailed explanation-5: -In plant anatomy, there are two main types of sieve elements. Companion cells and sieve cells originate from meristems, which are tissues that actively divide throughout a plant’s lifetime.