They can range in size from just a few inches tall to more than 12 feet in the case of the tree ferns. Some types of ferns are tropical. Others quite hardy. Their versatility aside, ferns are valuable in the home and garden because they prefer shade. In the landscape, ferns bring fresh green life to those hard-to-design dim corners.
Prokaryotic cells have various shapes; the four basic shapes are: Cocci - spherical Bacilli - rod shaped Spirochaete - spiral shaped Vibrio - comma shaped.
The Prokaryotic Cell. Prokaryotes are unicellular organisms that lack organelles or other internal membrane-bound structures . Therefore, they do not have a nucleus, but, instead, generally have a single chromosome: a piece of circular, double-stranded DNA located in an area of the cell called the nucleoid. Most prokaryotes have a cell wall outside the plasma membrane.