4.1
What Features of Cells Make Them the
Fundamental Unit of Life? 69
Cell size is limited by the surface
area-to-volume ratio 69
Microscopes are needed to visualize
cells 70
Cells are surrounded by a plasma membrane
72
Cells are prokaryotic or eukaryotic
72
4.2
What Are the Characteristics of Prokaryotic
Cells? 72
Prokaryotic cells share certain features
72
Some prokaryotic cells have specialized
features 73
4.3
What Are the Characteristics of Eukaryotic
Cells? 74
Compartmentalization is the key to
eukaryotic cell function 74
Organelles can be studied by microscopy
or isolated for chemical analysis
75
Some organelles process information
75
The endomembrane system is a group
of interrelated organelles 79
Some organelles transform energy 82
Several other organelles are surrounded
by a membrane 83
The cytoskeleton is important in cell
structure 86
4.4
What Are the Roles of Extracellular
Structures? 90
The plant cell wall is an extracellular
structure 90
The extracellular matrix supports
tissue functions in animals 91
4.5 How
Did Eukaryotic Cells Originate? 92
The endosymbiosis theory suggests
how eukaryotes evolved 92
Both prokaryotes and eukaryotes continue
to evolve 92
