Question

Pneumatophores are found in __________________.
a) The vegetation is found in marshy and saline lakes.
b) The vegetation is found in saline soil
c) Xerophytes
d) Epiphytes

Answer 1

Hint: These specialised aerial roots allow plants in habitats with waterlogged soil to breathe air. The roots may grow from the stem, or the typical roots may grow up.

Complete Answer:
Some botanists classify these as aerating roots if they come up from the soil, rather than aerial roots. The surface of these roots is covered with lenticel (small pores) that use air into spongy tissue that uses osmotic pathways to spread oxygen as required throughout the plant. Pneumatophores set Black mangrove and Grey mangrove apart from other mangrove species. Fishermen in some parts of Southeast Asia make corks for fishing nets by moulding the Sonneratia caseolaris pneumatophores (aka "Mangrove Apple") into small floats. Members of the Taxodiaceae subfamily produce woody structures above ground, known as cypress knees, which project up from their roots. Originally, these structures were thought to function as pneumatophores but new experiments left evidence for this hypothesis.The plant shoots pneumatophores when the soil on which a halophytic plant grows is highly salicin and largely anaerobic soil, to help in respiration. It is necessary to mention that the gaseous exchange done at leaves, even in other plants, is of minimal work for roots which are much further away. Roots absorb oxygen from the soil by themselves, dissolved. Since saline soil is largely anaerobic, however, it becomes impossible for the roots to exchange gases through the soil, and thus form pneumatophores that can directly absorb oxygen from air.

Hence the correct answer is option ‘b’ i.e "The vegetation is found in saline soil".

Note:This plant organ found in so many diverse plant families has various specialisations that accommodate the habitat of the plants. They can be technically classified as being either negatively gravitropic or positively gravitropic in common growth form.