Question

Plants which do not have roots, stems and leaves are known as

Answer 1

Plant body which is not differentiated into roots, stems and leaves is known as the thalloid body. This plant body lacks vascular tissues, say xylem and phloem as well.

Complete answer:
Bryophytes are known to have a thalloid body. Their body is characterized by the absence of well differentiated roots, stems or leaves; rather they have rhizoids which are thin roots like outgrowths. These structures help in providing soil anchorage to plants. Moreover, as these plants do not contain vascular tissues for conduction of water, they tend to dry up very quickly therefore these bryophytes are mostly found in the freshwater habitats. But their growth immediately deteriorates in the salt water. Thalloid plants are also known as foliose plants. They consist of mosses and liverworts. Liverworts are completely thalloid while in mosses, the axis is present which is a stem like structure. Bryophytes are capable of living in soil but water is needed for their sexual reproduction, therefore they are also known as the amphibians of the plantae kingdom.

Note: They usually inhabit shaded, humid and damp locations. Peat is a commercially used moss which is often used as fuel. It has got a very good water holding capacity and therefore can be used as a packing material for transporting live materials. They also help in formation of soil by colonizing rocks. Soil erosion caused by rains can also be prevented by these mosses. They form dense mats on soil, thereby preventing the erosion.