Page 12 - Demo 1

kernel or nucleus) do not have a membrane-bound nucleus. Their DNA is found
in a region of the cytoplasm called the nucleoid region, which is not enclosed
within an internal membrane. The other type of cell, eukaryoc cells (Greek; eu,
true), has a nucleus that houses its DNA.

Prokaryotes are single-celled organisms endowed with great capabilies
for survival as some of them need neither air nor organic maer to survive. The
two types of prokaryotes are the bacteria and the archaea. More than 5,000
species of prokaryotes are recognized, and many more exist that have not yet
been described. They exist in great numbers in the air, in the bodies of water,
in the soil, and even in the human body.

Prokaryoc cells are generally much smaller in size and simpler in
structure than eukaryoc cells. These characteriscs allow them to reproduce
very quickly and effecvely through binary fission. Inside the cell, there are no
interior compartments. Scaered throughout the cytoplasm are small structures
called ribosomes, where proteins are synthesized. On the outside, the cell of a
prokaryote is enclosed by a plasma membrane. Prokaryoc cells have lile or no
structural support aside from the cell wall that maintains the shape of the cell.
In bacteria, the cell wall is lined on the outside with a protecve layer of
polysaccharides, called the capsule.

Eukaryotes are much larger than prokaryotes, with a complex internal
structure such as the presence of compartments, membrane system, and
nucleus. Eukaryotes include prosts, fungi, plants, and animals.

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