Oh, the Variety!
The plant kingdom is much more diverse than most people think. Many
people just assume, well, they're all green and leafy-what's the difference? There
are many differences in the plant kingdom, like reproduction methods, structural
individuality, and locations. One type of plants that includes moss, liverwort, and
hornwort is called bryophytes. Other types are filicinophytes, coniferophytes,
and angiospermophytes. Each has its own destinct lifestyle, if you will, that
seperates it from other "green, leafy, things".
One of the first identifiers of a bryophyte is its waxy cuticule that helps the
plant retain water. Both male and female reproductive organs are present in
bryophytes, the male antheridium and the female archegonium. The fertilized egg
developes in the protection of the archegonium. Water is a very important part of
a bryophyte's life, not only for nutritional matters, but its sperm are flagellated,
meaning that they must swim to the egg to fertilize it. Most bryophytes do not
have vascular tissue, and therefore must beable to absorb water and desperse it
throughout the entire plant. Because they are non-vascular plants, bryophytes
do not have regular roots, but root-like rhizoids. This is a main reason that you
are most likely to find bryophytes such as mosses in damp, shaded areas.
A very small proportion of bryophytes lacks any special mechanism for spore
"liberation". The liverwort Riccia has the simplest known type of sporangonium
which is nothing but a capsule containing spores. At maturity, the capsule wall
disintegrates to expose the mass of spores which are completly set free when the
surrounding gametophytic tissues break down. These spores are much larger than
most wind-dispersed spores, so it is unclear how they are distributed as insect
distribution is almost unheard of with bryophytes.
The true f...