P-protein References P-protein plant structure Ask Anything Homework Help Written by The Information Architects of Encyclopaedia Britannica The Information Architects maintain a master list of the topics included in the corpus of Encyclopædia Britannica, and create and manage the relationships between them. The Information Architects of Encyclopaedia Britannica Britannica AI Ask Anything Learn about this topic in these articles: sieve element…by strands of cytoplasm called P-protein. It is not known whether P-protein is active in transport or merely serves as a seal against leakage in case of injury. See also phloem. Read More…by strands of cytoplasm called P-protein. It is not known whether P-protein is active in transport or merely serves as a seal against leakage in case of injury. See also phloem. Read More