61
J
ust as bricks and timbers are the structural units of a house
,
cells
are
the structural units of all living things, from one-celled “generalists” like amoebas to
complex multicellular organisms such as humans, dogs, and trees. Te human body
has 50 to 100 trillion of these tiny building blocks.
Tis chapter focuses on structures and functions shared by all cells. We address spe-
cialized cells and their unique functions in later chapters.
3
Cells: The Living Units
The Cellular Basis of Life
(p. 62)
The Plasma Membrane: Structure
(pp. 63–67)
The Fluid Mosaic Model (pp. 63–65)
The Glycocalyx (pp. 65–66)
Cell Junctions (pp. 66–67)
The Plasma Membrane: Membrane
Transport
(pp. 67–79)
Passive Processes (pp. 68–72)
Active Processes (pp. 72–79)
The Plasma Membrane: Generation of a
Resting Membrane Potential
(pp. 79–80)
Selective Diffusion Establishes Membrane
Potential (pp. 79–80)
Active Transport Maintains Electrochemical
Gradients (p. 80)
The Plasma Membrane: Cell-Environment
Interactions
(pp. 80–81)
Roles of Cell Adhesion Molecules
(CAMs) (p. 80)
Roles of Plasma Membrane Receptors
(p. 81)
Role of Voltage-Gated Membrane Channel
Proteins: Electrical Signaling (p. 81)
The Cytoplasm
(pp. 81–91)
Cytoplasmic Organelles (pp. 83–89)
Cellular Extensions (pp. 89–91)
The Nucleus
(pp. 91–96)
The Nuclear Envelope (pp. 92–93)
Nucleoli (p. 93)
Chromatin (pp. 93–96)
Cell Growth and Reproduction
(pp. 96–110)
The Cell Cycle (pp. 96–99)
Protein Synthesis (pp. 99–105)
Other Roles of DNA (pp. 105–109)
Degradation of Organelles and Cytosolic
Proteins (pp. 109–110)
Extracellular Materials
(p. 110)
Developmental Aspects of Cells
(pp. 110–111)
Apoptosis and Modified Rates of Cell
Division (p. 110)
Cell Aging (p. 111)
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