FORMS OF LIFE.
Discusses three stages of cellular evolution. First Common Ancestor (Universal Ancestor). Last Common Ancestor. Two basic forms of life: prokaryotes (single-celled); eukarotes (monocellular organisms) which have given rise to three kingdoms of multicellular organisms that exist. New types of cell divisions. DNA molecules.
There are basically two forms of life on earth: prokaryotes, which are cells without a nucleus, and eukarotes, which are cells which contain a nucleus... more
There are basically two forms of life on earth: prokaryotes, which are cells without a nucleus, and eukarotes, which are cells which contain a nucleus (Barbieri, 2001). Prokaryotes are found almost exclusively as single-celled organisms which can inhabit any ecological niche. They can exist with or without light, oxygen or organic molecules. They synthesize all their components from inorganic molecules, can rapidly adapt to environmental changes, and can exchange genes horizontally. Prokaryotes have a single circular DNA molecule, a single cell compartment and an exoskeleton.
Eukaryotes are mostly dependent on oxygen, and exists as monocellular organisms such as protozoa and protista, and have given rise to the three kingdoms of multicellular organisms that exist: plants, fungi and animals (Barbieri, 2001). They have