America's Source for High School Sports and the leading volleyball organization team up to honor the nation's best. (Week of 9/2-10/4).
Phloem Structure Phloem is composed of several cell types including sclerenchyma, parenchyma, sieve elements and companion cells. The sieve element and companion cell are found closely associated with each other in what is referred to as the sieve element/companion cell complex.
The sieve elements of angiosperms are sieve tube members, while the sieve elements of gymnosperms are sieve cells. Primary and secondary phloem is derived from the vascular cambium. Phloem may be primary or secondary, but in either case the sieve elements are nonliving cells. Only a and d are correct.