Answer:
B) cytoplasmic streaming in hyphae
Explanation:
Fungal mycelium refers to the branched vegetative structure of the fungi which is formed by the growth of the hyphae. The hyphae contain three zones of growth: the apical, subapical and zone of vacuolation.
The hyphae grow in the apical region which forms a branched structure in which the cytoplasm continuously moves between the hyphae at the point of fusion towards the growing tip. This movement of the cytoplasm towards the growing tip is known as "cytoplasmic streaming".
This streaming of cytoplasm is responsible for the formation of a zone of vacuolation and the mycelium is formed.
Thus, Option-B is the correct answer.
The growing tip eventually gives rise to a branch. This is the beginning of the branched mycelium. Growing tips that come in contact with neighbouring hyphae often fuse with them to form a hyphal net. In such a vigorously growing system, the cytoplasm is in constant motion, streaming toward the growing tips. Eventually, the older hyphae become highly vacuolated and may be stripped of most of their cytoplasm.
