Why are bryophytes called the amphibians of the plant kingdom?

Which among the following phyla is exclusively marine?

$(a)$ Associate any three phyla of Animalia with triploblastic body organisation and bilateral symmetry.
$(b)$ State the meaning of triploblastic body organisation and bilateral symmetry.
$(c)$ On the basis of presence or absence of coelom,compare the three phyla answered in $(a)$.

Define evolution.

$(i)$ To which division of Plantae do algae belong? Write one characteristic of the division. Give two examples.
$(ii)$ Name the group:
$(a)$ Which includes unicellular eukaryotic organisms.
$(b)$ In which the mode of nutrition is saprophytic.
$(c)$ In which seeds are not enclosed in fruit.
$(iii)$ Classify flowering plants on the basis of the number of cotyledons present in the seed.

Name the phylum to which Leech and Earthworm belong.