question_answer 25)

  Which among the following has specialised tissue for conduction of water? (i)  Thallophyta                  (ii) Bryophyta                     (iii)  Pteridophyta              (iv) Gymnosperms (a) (i) and (ii)                      (b) (ii) and (iii)                    (c) (iii) and (iv)                   (d) (i) and (iv)

Answer:

  (c) Pteridophyta are the oldest vascular plants and their body is differentiated into on aerial shoot system and an underground root system. All ferns fall under this group. They are the most developed seedless plants with few exception e.g., Selaginella. Gymnosperms are naked seed bearing plants. All conifers like pines, fern's, cedars and red 'woods are gymnosperms. They are vascular plants i.e., they have xylem and phloem for their conduction. Thallophytic have a body which is not differentiated into stem, roots and leaves. This kind of undifferentiated body is called thralls, hence the name halophytes is given to them. Algae and lichens are included in halophytes, Bryophytes are simple terrestrial plants and are also known as amphibians of plant kingdom. They do not have proper roots and leaves. Mosses, liverworts and hornworts are three groups of bryophytes. Both halophytes and bryouhytes are non-vascular plants i.e., they do not have xylem and phloem.