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Biology-Life Sciences

Standard C: Prokaryotic Cells, Eukaryotic Cells, and Viruses
Standard A: Plasma Membranes
Standard B: Enzymes
Standard C: Prokaryotic Cells, Eukaryotic Cells, and Viruses
Standard D: Central Dogma of Molecular Biology
Standard E : The endoplasmic reticulum and golgi apparatus
Standard F: Chloroplasts
Standard G: Mitochondria
Standard H: Macromolecules
Standard J : The Cytoskeleton and Cell Wall
Standard I : ATP production
Exemplar Chart

Prokaryotic cells lack internal membrane-bound structures and are unicellular organisms.  One example of a prokaryote is  bacteria.  Prokaryotic cells are about one-tenth the size of a eukaryotic cell. A prokaryote's DNA is double-stranded, and it prokaryotic cell is also experiences chemiosmosis.

Eukaryotic cells are multicellular organisms that have membrane-bound organelles, such as animal cells.  Some eukaryotic cells, however, are unicellular organisms such as amoebas.  Eukaryotic cells are present in all living things except bacteria. Eukaryotes experience chemiosmosis.


Viruses are disease-causing, nonliving particles composed of an inner core of nucleic acids surrounded by a capsid.  They have a plasma membrane, cell wall, and a proteins capsule. They also contain either RNA or DNA, which can be either single stranded or double stranded.  Viruses cannot make their own energy or reproduce, so they attack other host cells and use its energy to replicate themselves.  Compared to a eukaryotic cell, a virus is tiny. 

Prokaryotic vs. Eukaryotic
A prokaryotic cell is much smaller than a eukaryotic cell and has many less organelles.  An eukaryotic cell has distinct membrane-bound organelles such as mitochondria, ribosomes, golgi complex, endoplasmic reticulum, nucleus, chloroplasts, cell wall, plasma membrane, cytoplasm, vacuoles, centrioles, cilia, flagella, and lysosomes.  A prokaryotic cell simply has ribosomes, plasma membrane, and a cell wall.

Animal Cells vs. Plant Cells
Both animal cells and plant cells are eukarotes, but they differ in structure and organelles.  Animal cells have centrioles and mostly small lysosomes, while plant cells do not have centrioles and have larger lysosomes.  Plant cells are characterized by a cell wall, chloroplasts, and one large vacuole.

Comparing Viruses, Eukaryotes, and Prokaryotes
Out of the three, Eukaryotes are by far the largest.  Prokaryotic cells are next, about one-tenth the size of a eukaryotic cell.  Viruses are much, much smaller than prokaryotes.  Prokaryotic and Eukaryotic cells are both alive, while viruses are not.  Viruses have very few organelles, similar to the prokaryotic cells.  They contain a plasma membrane, cell wall, RNA or DNA, and a protein capsule.   

Diagram of a Retrovirus