
Prokaryote

Eukaryote

Plant Cell

Animal Cell
Can be
multicellular or
unicellular
 Does not have a
cell wall
 Uses
photosynthesis
 Unicellular

"Karyose" comes from a Greek word
which means "kernel," as in a kernel of
grain. In biology, we use this word root to
refer to the nucleus of a cell.
 "Pro" means "before," and "eu" means
"true," or "good." Prokaryotic cells have
no nuclei, while eukaryotic cells do have
true nuclei.

There are four major similarities between
prokaryotic and eukaryotic cells
 1. DNA, the genetic material contained
in one or more chromosomes and
located in a nonmembrane bound
nucleoid region in prokaryotes and a
membrane-bound nucleus in eukaryotes


2. Plasma membrane, a phospholipid
bilayer with proteins that separates the
cell from the surrounding environment
and functions as a selective barrier for
the import and export of materials

3. Cytoplasm, the rest of the material of
the cell within the plasma membrane,
excluding the nucleoid region or
nucleus, that consists of a fluid portion
called the cytosol and the organelles
and other particulates suspended in it

4. Ribosomes, the organelles on which
protein synthesis takes place
Prokaryotes, which include all bacteria
and archaea (archaebacteria), are the
simplest cellular organisms.
 Prokaryotic cells are fundamentally
different from eukaryotic cells. Notably,
prokaryotic cells lack a nucleus and
membranous organelles.

The walls of bacteria consist of
peptidoglycans. Sometimes there is also
an outer capsule.
 Some bacteria have flagella which are
used for locomotion and/or pili, which
may be used to pull two cells in close
contact

Eukaryotic cells contain a membranebound nucleus and numerous membraneenclosed organelles not found in
prokaryotes.
 The nucleus is bounded by the nuclear
envelope, a double membrane with many
nuclear pores through which material
enters and leaves. Animals, plants, fungi,
and protists are all eukaryotes. Eukaryotic
cells are more complex than prokaryotic
cells.


4.6 billion years ago the Earth was formed

3.5 billion years ago the first life arose:
prokaryotic bacteria

1.5 billion years ago eukaryotic cells arose

0.5 billion years ago the Cambrian
explosion – multi-celled eukaryotes arose

3 million years ago our earliest ancestors,
the hominids, appeared

Eukaryotes are, on average, 10 times the
size of prokaryotes