Class notes Biology

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Characteristics of microorganisms

Prokaryotes:

Prokaryotes are a group of organisms that lack a cell nucleus or any other membrane-
bounded organelles.

Eukaryotes:

Eukaryotes is an organism whose cells contain complex structures enclosed within
membranes.

Difference between Prokaryotic and Eukaryotic cells:

Prokaryotic cells:

 They are unicellular organisms.
 These are small and simple cells.
 The genetic material of a prokaryotic cell is not enclosed in a nucleus.
 The genetic material is either in a loop or small rings of DNA.
 They are free-floating in the cell.
 They also have a cell wall, cell membrane, and cytoplasm but no membrane-bounded
organelles.

Example:

Bacteria

Eukaryotic cells:

 They can be unicellular or multicellular organisms.
 Big and complex cells.
 The genetic material of a eukaryotic cell is enclosed in a nucleus.
 They also contain a cell wall, cell membrane, cytoplasm, and other membrane-bounded
organelles.

Examples:

Animals and plants.

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Bacteria

1. Unicellular, Microscopic organism.
2. Prokaryotes.
3. Singular is referred to as Bacterium.
4. Study of Bacteria Bacteriology.
5. Most bacteria are 0.2 um 100 um.