Why are bryophytes called the amphibians of the plant kingdom?

Why are bryophytes called the amphibians of the plant kingdom?

Answer:
The plant bodies of bryophytes are devoid of vascular tissues and roots. So they live in moist habitats in order to obtain water directly or through rhizoids. Moreover, like the amphibians of animal kingdom, the sperms of bryophytes require an external water medium for reaching the eggs. Due to this reason, bryophytes are called the amphibians of the plant kingdom.