A Tour of the Cell
 Categories of Cells
 Features of Prokaryotic Cells
 Features of Eukaryotic Cells
o Membrane Structure
o Nucleus and Ribosomes
o Endoplasmic Reticulum (ER)
o Golgi Apparatus
o Lysosomes
o Vacuoles
 Energy
o
Converting Organelles
Chloroplasts
o Mitochondria
 Cytoskeleton
o
Cell Shape
o Cell Movement
Proteins and Lipids Leave the ER Enroute to the Golgi
Chromatin
Nucleolus
Nuclear envelope
Nucleus
Smooth endoplasmic
reticulum
Mitochondrion
Cytosol
Lysosome
Centrioles
Centrosome
matrix
Cytoskeletal
elements
• Microtubule
• Intermediate
filaments
Plasma
membrane
Rough
endoplasmic
reticulum
Ribosomes
Golgi apparatus
Secretion being
released from cell
by exocytosis
Peroxisome
Proteins Are Transported in Vesicles to the Golgi
Figure 4.11
The Golgi Apparatus
• The Golgi apparatus
– Refines, stores, and distributes the chemical products of
cells.
– Acts like a finishing and shipping station (UPS or FedEx)
in the cell
A Tour of the Cell
 Categories of Cells
 Features of Prokaryotic Cells
 Features of Eukaryotic Cells
o Membrane Structure
o Nucleus and Ribosomes
o Endoplasmic Reticulum (ER)
o Golgi Apparatus
o Lysosomes
o Vacuoles
 Energy
o
Converting Organelles
Chloroplasts
o Mitochondria
 Cytoskeleton
o
Cell Shape
o Cell Movement
Focus on Lysosomes
Chromatin
Nucleolus
Nuclear envelope
Nucleus
Smooth endoplasmic
reticulum
Mitochondrion
Cytosol
Lysosome
Centrioles
Centrosome
matrix
Cytoskeletal
elements
• Microtubule
• Intermediate
filaments
Plasma
membrane
Rough
endoplasmic
reticulum
Ribosomes
Golgi apparatus
Secretion being
released from cell
by exocytosis
Peroxisome
Lysosomes
• A lysosome is a membrane-enclosed sac containing
digestive enzymes
– The enzymes break down macromolecules and ingested
debris within vacuoles
– Serves as the “Greeting and Garbage Service” of the cell
Lysosome Formation
Proteins and Lipids Move Through the Endomembrane System
Rough ER
Phagosome
ER
membrane
Proteins in
cisterna
Plasma
membrane
Pathway C:
Lysosome containing
acid hydrolase
enzymes
Vesicle becomes
lysosome
Golgi
apparatus
Pathway A:
Vesicle contents
destined for exocytosis
Secretory
vesicle
Secretion by
exocytosis
Pathway B:
Vesicle membrane
to be incorporated
into plasma
membrane
Extracellular fluid
3 Fates: A. Exocytosis (export)
B. Becomes part of membrane
C. Becomes a lysosome
Figure 3.20
A Tour of the Cell
 Categories of Cells
 Features of Prokaryotic Cells
 Features of Eukaryotic Cells
o Membrane Structure
o Nucleus and Ribosomes
o Endoplasmic Reticulum (ER)
o Golgi Apparatus
o Lysosomes
o Vacuoles & Peroxisomes
 Energy
o
Converting Organelles
Chloroplasts
o Mitochondria
 Cytoskeleton
o
Cell Shape
o Cell Movement
Focus on Vacuoles and Perioxisomes
Chromatin
Nucleolus
Nuclear envelope
Nucleus
Smooth endoplasmic
reticulum
Mitochondrion
Cytosol
Lysosome
Centrioles
Centrosome
matrix
Cytoskeletal
elements
• Microtubule
• Intermediate
filaments
Plasma
membrane
Rough
endoplasmic
reticulum
Ribosomes
Golgi apparatus
Secretion being
released from cell
by exocytosis
Peroxisome
A Tour of the Cell
 Categories of Cells
 Features of Prokaryotic Cells
 Features of Eukaryotic Cells
o Membrane Structure
o Nucleus and Ribosomes
o Endoplasmic Reticulum (ER)
o Golgi Apparatus
o Lysosomes
o Vacuoles
 Energy
o
Converting Organelles
Chloroplasts
o Mitochondria
 Cytoskeleton
o
Cell Shape
o Cell Movement
Mitochondria
• Mitochondria are energy conversion factories
• Food energy is converted into usable cellular
energy (ATP) through cellular respiration
Cell Respiration:
Food energy +
oxygen gas
Carbon dioxide +
water + ATP
A Tour of the Cell
 Categories of Cells
 Features of Prokaryotic Cells
 Features of Eukaryotic Cells
o Membrane Structure
o Nucleus and Ribosomes
o Endoplasmic Reticulum (ER)
o Golgi Apparatus
o Lysosomes
o Vacuoles
 Energy
o
Converting Organelles
Chloroplasts
o Mitochondria
 Cytoskeleton
o
Cell Shape
o Cell Movement
Cytoskeleton: Microtubules, Intermediate Filaments, Microfilaments
Chromatin
Nucleolus
Nuclear envelope
Nucleus
Smooth endoplasmic
reticulum
Mitochondrion
Cytosol
Lysosome
Centrioles
Centrosome
matrix
Cytoskeletal
elements
• Microtubule
• Intermediate
filaments
Plasma
membrane
Rough
endoplasmic
reticulum
Ribosomes
Golgi apparatus
Secretion being
released from cell
by exocytosis
Peroxisome
Cytoskeleton Made of Microfilaments, Intermediate filaments, and Microtubules
Cell-cell junctions
Muscle contracts
using actin protein
(and myosin)
Cells divide in half with the
pinching action of
microfilaments
Organelle towing
A Tour of the Cell
 Categories of Cells
 Features of Prokaryotic Cells
 Features of Eukaryotic Cells
o Membrane Structure
o Nucleus and Ribosomes
o Endoplasmic Reticulum (ER)
o Golgi Apparatus
o Lysosomes
o Vacuoles
 Energy
o
Converting Organelles
Chloroplasts
o Mitochondria
 Cytoskeleton
o
Cell Shape
o Cell Movement
o Cell Junctions
Cell Junctions: Tight, Desmosomes, and Gap
Tight junctions: Impermeable
junctions prevent molecules from
passing through the intercellular space.
Desmosomes: Anchoring junctions bind
adjacent cells together and help form an
internal tension-reducing network of
fibers.
Gap junctions: Communicating junctions allow ions and
small molecules to pass from one cell to the next for
intercellular communication.
Testing Diagrams of Cells
A Tour of the Cell
 Categories of Cells
 Features of Prokaryotic Cells
 Features of Eukaryotic Cells
o Membrane Structure
o Nucleus and Ribosomes
o Endoplasmic Reticulum (ER)
o Golgi Apparatus
o Lysosomes
o Vacuoles
 Energy
o
Converting Organelles
Chloroplasts
o Mitochondria
 Cytoskeleton
o
Cell Shape
o Cell Movement