EVERYDAY SCIENCE

Detailed explanation-1: -According to this theory, the apical region of the shoot consists of two zones: Tunica – It is the outer enveloping layer, made up of small cells that give rise to the epidermis and outer cortex. Corpus – It is the mass of cells forming the inner core. It produces the inner cortex, procambium and pith.

Detailed explanation-2: -Schmidt differentiated two tissue zones in the shoot apex and named them tunica and corpus.

Detailed explanation-3: -The structure and organization of shoot apex includes the following: it is convex in shape or they are slightly elongated at the base. It is mainly divided into four regions as tunica, corpus, flank meristem, and rib meristem.

Detailed explanation-4: -The apical meristem or growing region lies behind the root cap. The promeristem as in the stem, early differentiates into three regions. At the embryonic stage the root apical meristem is organized opposite to the shoot apex.

Detailed explanation-5: -In the following theory, it is said that the shoot apex of the angiosperms has two distinct zones. Peripheral zone that is present is called tunica and the central zone is called corpus. The tunica divides only in anticlinal planes and the corpus divides in various planes. Hence, the correct answer is option (D).