Chapter
4
The Tissue
Level of
Organization
PowerPoint® Lecture Slides
prepared by Jason LaPres
Lone Star College - North Harris
Copyright © 2010 Pearson Education, Inc.
Copyright © 2010 Pearson Education, Inc.
4-1 The four tissue types
are epithelial, connective,
muscle, and neural
Copyright © 2010 Pearson Education, Inc.
Four Types of Tissues
• Tissues are collections of cells and cell
products that perform specific, limited
functions
Copyright © 2010 Pearson Education, Inc.
Tissues of the Body
Figure 4-1
Copyright © 2010 Pearson Education, Inc.
4-2 Epithelial tissue covers
body surfaces, lines cavities
and tubular structures, and
serves essential functions
Copyright © 2010 Pearson Education, Inc.
Epithelial Tissues
• Characteristics of Epithelia
– Cellularity (cell junctions)
– Polarity (apical and basal surfaces)
– Attachment
– Avascularity
– Regeneration
Copyright © 2010 Pearson Education, Inc.
Epithelial Tissues
• Functions of Epithelial Tissue
– Provide physical protection
– Control permeability
– Provide sensation
– Produce specialized secretions (glandular
epithelium)
Copyright © 2010 Pearson Education, Inc.
Intercellular Connections
• Support and Communication
– CAMs (cell adhesion molecules):
• Transmembrane proteins
– Intercellular cement:
• Proteoglycans
– Hyaluronan (hyaluronic acid):
• Glycosaminoglycans
Copyright © 2010 Pearson Education, Inc.
Intercellular Connections
• Cell junctions
– Form bonds with other cells or extracellular material:
• Occluding (tight) junctions
• Gap junctions
• Macula adherens (desmosomes)
Intercellular Connections
Copyright © 2010 Pearson Education, Inc.
Intercellular Connections
Figure 4-2
Copyright © 2010 Pearson Education, Inc.
Intercellular Connections
Figure 4-2
Copyright © 2010 Pearson Education, Inc.
Intercellular Connections
Figure 4-2
Copyright © 2010 Pearson Education, Inc.
Intercellular Connections
Figure 4-2
Copyright © 2010 Pearson Education, Inc.
The Surface of Epithelial Cells
Figure 4-3
Copyright © 2010 Pearson Education, Inc.
Epithelial Renewal and Repair
• Epithelia are replaced by division of
germinative cells (stem cells)
• Near basal lamina
Copyright © 2010 Pearson Education, Inc.
4-3 Cell shape and number of
layers determine the
classification of epithelia
Copyright © 2010 Pearson Education, Inc.
Classification of Epithelia
• Singular epithelium; plural epithelia
• Classes of Epithelia
– Based on layers:
• Simple epithelium: single layer of cells
• Stratified epithelium: several layers of cells
– Based on shape:
• Squamous epithelia: thin and flat
• Cuboidal epithelia: square shaped
• Columnar epithelia: tall, slender rectangles
Copyright © 2010 Pearson Education, Inc.
Copyright © 2010 Pearson Education, Inc.
Classification of Epithelia
Figure 4-4
Copyright © 2010 Pearson Education, Inc.
Classification of Epithelia
Figure 4-4
Copyright © 2010 Pearson Education, Inc.
Classification of Epithelia
Figure 4-4
Copyright © 2010 Pearson Education, Inc.
Classification of Epithelia
Figure 4-5
Copyright © 2010 Pearson Education, Inc.
Classification of Epithelia
Figure 4-5
Copyright © 2010 Pearson Education, Inc.
Classification of Epithelia
Figure 4-5
Copyright © 2010 Pearson Education, Inc.
Glandular Epithelia
• Endocrine Glands
– Release hormones:
• Into interstitial fluid
• No ducts
• Exocrine Glands
– Produce secretions:
• Onto epithelial surfaces
• Through ducts
Mechanisms of Glandular Secretion
Copyright © 2010 Pearson Education, Inc.
Glandular Epithelia
• Mechanism of Secretion
– Merocrine secretion:
• Is produced in Golgi apparatus
• Is released by vesicles (exocytosis)
• For example, sweat glands
– Apocrine secretion:
• Is produced in Golgi apparatus
• Is released by shedding cytoplasm
• For example, mammary gland
– Holocrine secretion:
• Is released by cells bursting, killing gland cells
• Gland cells replaced by stem cells
• For example, sebaceous gland
Copyright © 2010 Pearson Education, Inc.
Mechanisms of Secretion
Figure 4-6
Copyright © 2010 Pearson Education, Inc.
Glandular Epithelia
• Types of Secretions
– Serous glands:
• Watery secretions
– Mucous glands:
• Secrete mucins
– Mixed exocrine glands:
• Both serous and mucous
Copyright © 2010 Pearson Education, Inc.
Copyright © 2010 Pearson Education, Inc.
4-4 Connective tissue
provides a protective
structural framework for other
tissue types
Copyright © 2010 Pearson Education, Inc.
Connective Tissues
• Characteristics of Connective Tissues
– Specialized cells
– Solid extracellular protein fibers
– Fluid extracellular ground substance
• The extracellular components of connective
tissues (fibers and ground substance) make up
the matrix
– Majority of tissue volume
– Determines specialized function
Copyright © 2010 Pearson Education, Inc.
Connective Tissues
• Support and protection
• Transportation of materials
• Storage of energy reserves
• Defense of the body
Copyright © 2010 Pearson Education, Inc.
Major Types of Connective Tissue
Figure 4-7
Copyright © 2010 Pearson Education, Inc.
Connective Tissues
• Cell Types of Connective Tissue
Proper
– Fibroblasts
– Macrophages
– Adipocytes
– Mast cells
Copyright © 2010 Pearson Education, Inc.
Connective Tissues
• Connective Tissue Fibers
– Collagen fibers
– Reticular fibers
– Elastic fibers
Copyright © 2010 Pearson Education, Inc.
Connective Tissues
• Ground Substance
– Is clear, colorless, and viscous
– Fills spaces between cells and slows
pathogen movement
Copyright © 2010 Pearson Education, Inc.
Types of Connective Tissue Proper
• Loose Connective Tissue
– More ground substance, less fibers
– For example, fat (adipose tissue)
• Dense Connective Tissue
– More fibers, less ground substance
– For example, tendons
Copyright © 2010 Pearson Education, Inc.
Cells and Fibers of Connective Tissue
Proper
Figure 4-8
Copyright © 2010 Pearson Education, Inc.
Connective Tissue Proper
Figure 4-9
Copyright © 2010 Pearson Education, Inc.
Connective Tissue Proper
Figure 4-9
Copyright © 2010 Pearson Education, Inc.
Connective Tissue Proper
Figure 4–9
Copyright © 2010 Pearson Education, Inc.
Connective Tissues
• Fluid Connective Tissues
– Blood and lymph
– Watery matrix of dissolved proteins
– Carry specific cell types (formed elements)
• Formed elements of blood
– red blood cells (erythrocytes)
– white blood cells (leukocytes)
– platelets
Copyright © 2010 Pearson Education, Inc.
Supportive Connective Tissues
• Cartilage
– Gel-type ground substance
– For shock absorption and protection
• Bone
– Calcified (made rigid by calcium salts, minerals)
– For weight support
Copyright © 2010 Pearson Education, Inc.
Supportive Connective Tissues
• Cartilage Matrix
– Proteoglycans derived from chondroitin sulfates
– Ground substance proteins
• Chondrocytes (cartilage cells) surrounded by
lacunae (chambers)
Copyright © 2010 Pearson Education, Inc.
Supportive Connective Tissues
• Cartilage Structure
– No blood vessels:
• Chondrocytes produce antiangiogenesis factor
– Perichondrium:
• Outer, fibrous layer (for strength)
• Inner, cellular layer (for growth and maintenance)
Copyright © 2010 Pearson Education, Inc.
Supportive Connective Tissues
• Types of Cartilage
– Hyaline cartilage:
• Stiff, flexible support
• Reduces friction between bones
• Found in synovial joints, rib tips, sternum, and trachea
– Elastic cartilage:
• Supportive but bends easily
• Found in external ear and epiglottis
– Fibrous cartilage (fibrocartilage):
•
•
•
•
Limits movement
Prevents bone-to-bone contact
Pads knee joints
Found between pubic bones and intervertebral discs
Copyright © 2010 Pearson Education, Inc.
Types of Cartilage
Figure 4-10
Copyright © 2010 Pearson Education, Inc.
Types of Cartilage
Figure 4-10
Copyright © 2010 Pearson Education, Inc.
Types of Cartilage
Figure 4-10
Copyright © 2010 Pearson Education, Inc.
Supportive Connective Tissues
• Bone or osseous tissue
– Strong (calcified: calcium salt deposits)
– Resists shattering (flexible collagen fibers)
• Bone cells or osteocytes
– Arranged around central canals within matrix
– Small channels through matrix (canaliculi) access
blood supply
• Periosteum
– Covers bone surfaces
– Fibrous layer
– Cellular layer
Copyright © 2010 Pearson Education, Inc.
Bone
Figure 4-11
Copyright © 2010 Pearson Education, Inc.
Copyright © 2010 Pearson Education, Inc.
4-5 Membranes are physical
barriers of four types: mucous,
serous, cutaneous, and
synovial
Copyright © 2010 Pearson Education, Inc.
Membranes
• Membranes
– Are physical barriers
– That line or cover portions of the body
– Consist of:
• An epithelium
• Supported by connective tissues
Copyright © 2010 Pearson Education, Inc.
Membranes
• Four Types of Membranes
– Mucous membranes
– Serous membranes
– Cutaneous membrane
– Synovial membranes
Copyright © 2010 Pearson Education, Inc.
Membranes
• Mucous Membranes (Mucosae)
– Line passageways that have external connections
– In digestive, respiratory, urinary, and reproductive
tracts
– Epithelial surfaces must be moist:
• To reduce friction
• To facilitate absorption and excretion
– Lamina propria:
• Is areolar tissue
Copyright © 2010 Pearson Education, Inc.
Membranes
• Serous Membranes
– Line cavities not open to the outside
– Are thin but strong
– Have fluid transudate to reduce friction
– Have a parietal portion covering the cavity
– Have a visceral portion (serosa) covering the
organs
Copyright © 2010 Pearson Education, Inc.
Membranes
• Three Serous Membranes
– Pleura:
• Lines pleural cavities
• Covers lungs
– Peritoneum:
• Lines peritoneal cavity
• Covers abdominal organs
– Pericardium:
• Lines pericardial cavity
• Covers heart
Copyright © 2010 Pearson Education, Inc.
Membranes
Figure 4-12
Copyright © 2010 Pearson Education, Inc.
Membranes
• Cutaneous Membrane
– Is skin, surface of the body
– Thick, waterproof, and dry
• Synovial Membranes
– Line moving, articulating joint cavities
– Produce synovial fluid (lubricant)
– Protect the ends of bones
– Lack a true epithelium
Copyright © 2010 Pearson Education, Inc.
Membranes
Figure 4-12
Copyright © 2010 Pearson Education, Inc.
4-6 The three types of muscle
tissue are skeletal, cardiac,
and smooth
Copyright © 2010 Pearson Education, Inc.
Muscle Tissue
• Specialized for contraction
• Produces all body movement
• Three types of muscle tissue
– Skeletal muscle:
• Large body muscles responsible for movement
– Cardiac muscle:
• Found only in the heart
– Smooth muscle:
• Found in walls of hollow, contracting organs (blood vessels;
urinary bladder; respiratory, digestive, and reproductive
tracts)
Copyright © 2010 Pearson Education, Inc.
Muscle Tissue
Figure 4-13
Copyright © 2010 Pearson Education, Inc.
Muscle Tissue
Figure 4-13
Copyright © 2010 Pearson Education, Inc.
Muscle Tissue
Figure 4-13
Copyright © 2010 Pearson Education, Inc.
4-7 Neural tissue responds to
stimuli and conducts electrical
impulses throughout the body
Copyright © 2010 Pearson Education, Inc.
Neural Tissue
• Also called nervous or nerve tissue
– Specialized for conducting electrical impulses
– Rapidly senses internal or external
environment
– Processes information and controls
responses
Copyright © 2010 Pearson Education, Inc.
Neural Tissue
• Neural tissue is concentrated in the
central nervous system
– Brain
– Spinal cord
Copyright © 2010 Pearson Education, Inc.
Neural Tissue
• Two Kinds of Neural Cells
– Neurons:
• Nerve cells
• Perform electrical communication
– Neuroglia:
• Supporting cells
• Repair and supply nutrients to neurons
Copyright © 2010 Pearson Education, Inc.
Neural Tissue
• Cell Parts of a Neuron
– Cell body:
• Contains the nucleus and nucleolus
– Dendrites:
• Short branches extending from the cell body
• Receive incoming signals
– Axon (nerve fiber):
• Long, thin extension of the cell body
• Carries outgoing electrical signals to their destination
Copyright © 2010 Pearson Education, Inc.
Neural Tissue
Figure 4-14
Copyright © 2010 Pearson Education, Inc.
4-8 The response to tissue
injury involves inflammation
and regeneration
Copyright © 2010 Pearson Education, Inc.
Tissue Injuries and Repair
• Tissues respond to injuries to maintain
homeostasis
– Cells restore homeostasis with two
processes:
• Inflammation
• Regeneration
Copyright © 2010 Pearson Education, Inc.
Tissue Injuries and Repair
• Inflammation = inflammatory response
– The tissue’s first response to injury
• Signs and symptoms of the inflammatory
response include
– Swelling
– Redness
– Heat
– Pain
Copyright © 2010 Pearson Education, Inc.
Tissue Injuries and Repair
• Inflammatory Response
– Can be triggered by:
• Trauma (physical injury)
• Infection (the presence of harmful pathogens)
Copyright © 2010 Pearson Education, Inc.
4-9 With advancing age,
tissue repair declines and
cancer rates increase
Copyright © 2010 Pearson Education, Inc.
Aging and Tissue Structure
• Speed and efficiency of tissue repair
decrease with age due to
– Slower rate of energy consumption
(metabolism)
– Hormonal alterations
– Reduced physical activity
Copyright © 2010 Pearson Education, Inc.
Aging and Cancer Incidence
• Cancer rates increase with age
– 1 in 4 people in the United States develops cancer
– Cancer is the #2 cause of death in the United States
– Environmental chemicals and cigarette smoke cause
cancer
Copyright © 2010 Pearson Education, Inc.