Download Chapter 3, part A

Chapter 3a
Compartmentation:
Cells and Tissues
About this Chapter
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Body compartments
Biological membranes
Intracellular compartments
Tissue types and characteristics
Tissue remodeling
Organs
Three Major Body Cavities
POSTERIOR
ANTERIOR
Cranial cavity
Pleural
sac
Pericardial Thoracic
cavity
sac
Diaphragm
Abdominal
cavity
Pelvic
cavity
Abdominopelvic
cavity
Figure 3-1
Body Cavities
Lumens of Hollow Organs
• Hollow organs
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Heart
Lungs
Blood vessels
Intestines
• Lumen
• Not the internal environment
Functional Compartments
1. Outside Body
2. Extracellular fluid
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Plasma
Interstitial fluid
3. Intracellular fluid
4. Organelles and vacuoles
Body Fluid Compartments
Capillary wall
Cell membrane
Blood
cells
Blood vessel
Plasma
Interstitial fluid
Intracellular fluid
ECF
ICF
Cell
membrane
Figure 3-2
Cell Membrane: Overview
• Membranes in the body
Pericardial Loose connective
tissue
membrane
Cell
Heart
The pericardial membrane is a Seen magnified, the pericardial
tissue that surrounds the heart.
membrane is a layer of flattened
epithelial cells supported by
connective tissue.
Each cell of the
pericardial membrane
has a cell membrane
surrounding it.
The cell membrane
is a phospholipid
bilayer.
Figure 3-3
Cell Membrane: Functions
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Physical barrier
Gateway for exchange
Communication
Cell structure
Cell Membrane: Structure
• The fluid mosaic model of a biological
membrane
Carbohydrate group
of glycoprotein
Carbohydrate group
of glycolipid
Extracellular surface
of membrane
Membrane
splits into layers
in freeze-fracture
electron
microscopy.
Proteins
Intracellular
surface of
membrane
Cholesterol
molecules insert
themselves into
the lipid layer.
Lipid tails form the interior
layer of the membrane.
Phospholipid heads face the
aqueous intracellular and
extracellular compartments.
Figure 3-4
Cell Membrane: Composition
• Lipids
• Phospholipids
• Sphingolipids
• Cholesterol
• Proteins
• Integral
• Peripheral
• Lipid-anchored
Cell Membrane: Composition
Table 3-1
Cell Membrane: Structure and Formation
• Phospholipids have polar and non-polar
regions
(a)
Phospholipid molecules have polar heads and nonpolar tails.
The “R” group is a variable polar group.
Polar head
(hydrophilic)
Nonpolar
fatty acid
tail
(hydrophobic)
Structural model
Molecular models
Stylized model
Figure 3-5a
Cell Membrane: Formation
• Membrane phospholipids form
bilayers, micelles, or liposomes
Phospholipids arrange themselves so that their
nonpolar tails are not in contact with aqueous
solutions such as extracellular fluid.
(b)
Tails
Phospholipid bilayer
forms a sheet.
Micelles are droplets
of phospholipids.
Liposomes have
an aqueous center.
Figure 3-5b
Cell Membrane: Proteins
• The three types of membrane proteins:
integral, peripheral, and lipid-anchored
Integral
(transmembrane)
protein
Glycoprotein
Peripheral protein
Lipid-anchored
proteins
Peripheral
protein
Cytoskeleton
proteins
Cytoplasm
Figure 3-6
Cell Membrane: Lipid Rafts
• Sphingolipids and alkaline phosphatase
Figure 3-8
Cell Membrane Components
CELL MEMBRANE
consists of
Cholesterol
Phospholipids, Sphingolipids
together form
together form
Lipid bilayer
Glycolipids
Carbohydrates
Proteins
together form
Glycoproteins
functions as
whose functions include
Selective barrier
between cytosol and
external environment
Structural
stability
Cell
recognition
Immune
response
Figure 3-9
Intracellular Compartments
• Cytoplasm
• Cytosol
• Inclusions
• Organelles
• Nucleus
Cell Compartments
THE CELL
• A map for the
study of cell
structure
is composed of
Cell
membrane
Nucleus
Cytosol
Cytoplasm
Membranous
organelles
• Mitochondria
• Endoplasmic
reticulum
• Golgi
complex
• Lysosomes
• Peroxisomes
Inclusions
• Lipid droplets
• Glycogen granules
• Ribosomes
• Vaults
• Proteasomes
• Cytoskeleton
• Centrioles
• Centrosomes
• Cilia
• Flagella
Extracellular fluid
Figure 3-11
Inclusions Have No Membranes
• Ribosomes
• Free
• Fixed
• Polyribosomes
• Proteasomes
• Vaults
• RNA/protein
Cytoplasmic Proteins Fibers
• Actin (microfilaments)
• Intermediate
• Myosin
• Keratin
• Neurofilaments
• Microtubules
• Tubulin
• Centrioles, cilia, flagella
Microtubule function
• Centrioles
• Pull chromosomes
• Form core in cilia
• Cilia and flagella
• Fluid movement
Centrioles
Figure 3-13a–b
Cilia and Flagella
Figure 3-13c–d
Cytoskeleton: Function
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Cell shape
Internal organization
Intracellular transport
Assembly of cells into tissues
Movement
Cytoskeleton and Cytoplasmic Protein Fibers
Microvilli increase
cell surface area.
They are supported
by microfilaments.
Microfilaments form
a network just inside
the cell membrane.
Microtubules
are the largest
cytoskeleton fiber.
Intermediate
filaments include
myosin and keratin.
(a)
(b)
Figure 3-14
Cytoskeleton and Cytoplasmic Protein Fibers
• Motor proteins move on cytoskeletal fibers
Organelle
Motor
protein
ATP
Direction of
movement
Cytoskeletal fiber
Figure 3-15
Mitochondria
• Membrane-enclosed compartments
• Unique DNA
• Site of cellular ATP generation
Mitochondria
Inner membrane
Matrix is the
innermost
compartment.
Matrix
Cytoplasm
of cell
Outer
membrane
Cristae
The intermembrane
space forms
a compartment.
Cytosolic side
of membrane
Figure 3-16
Endoplasmic Reticulum (ER)
• Smooth ER
• Synthesis of fatty acids, steroids, lipids
• Modified forms in liver, kidney, muscles
• Rough ER
• Rows of ribosomes
• Protein assembly and modification
Endoplasmic Reticulum
Ribosomes are attached
to cytosolic side of rough
endoplasmic reticulum.
Endoplasmic
reticulum
Lumen of
endoplasmic
reticulum
Smooth
endoplasmic
reticulum
Figure 3-17