Prokaryote:
- Do not have membrane bound organelles.
The DNA of prokaryotes is simple in
structure and floats freely in the cell.
The cell walls typically consist of
peptidoglycan molecules.
- The cell wall of prokaryotes is a fluid
phospholipid bilayer having no carbohydrates
on the membrane and typically no sterols.
Although the membrane does have hopanoids
(which are sterol like) molecules.
Eukaryote:
- Eukaryotes have membrane bound
organelles. Their DNA is complex and
typically associated with structural and
regulatory proteins and it is contained
within a membrane bound nucleus. The cells
are about ten times larger then those of
prokaryotes. Some eukaryotes (e.g. plants)
have cell walls but are not made up of
peptidoglycan molecules.
- Replication in prokaryotes involves
mitosis and meiosis. Meiosis occurs in sex
cells like sperm and egg. The eukaryote
cell member is a fluid phospholipid bilayer
containing sterols and carbohydrates. The
membranes can endocytose, phagocytose,
pinocytose and exocytose.
- In animal cells the plasma membrane is
the only separation between the cell�s
interior and the environment.
- In fungi, bacteria and plants there is
an additional cell wall as the outer most
boundary.
- The plasma membrane is about 10 nm thick
and is a selective barrier.
Cell wall: A cell membrane is a lipid bilayer that
usually has proteins associated with its surface, interior or even
transmembrane.
The membrane is selectively permeable.
Microbe Evolution: The concept of common evolutionary
ancestor is introduced.
Cell Mobility and Locomotion:
The motion of eukaryotes and prokaryotes when done using flagella is
fundamentally different. Structurally the flagella are different
and eukaryotes typically used ATP (myosin) as an energy source to
drive the motion of the flagella.
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