anatch3-3
DESCRIPTION
Connective tissueTRANSCRIPT
TissuesChapter 3.3
Connective Tissue
Connective Tissue• Found everywhere in
the body– Never exposed to the
outside environment• Includes the most
abundant and widely distributed tissues
• Functions– Binds body tissues
together– Supports the body– Provides protection– Transports materials
• Variations in blood supply– Some tissue types are
well vascularized– Some have poor blood
supply or are avascular
• Have receptors for– Pain, pressure,
temperature• Extracellular matrix
– Non-living material that surrounds living cells
Extracellular Matrix• Two main elements
– Ground substance – mostly water along with adhesion proteins and polysaccharide molecules
– Fibers• Produced by the cells• Three types
– Collagen fibers– Elastic fibers– Reticular fibers
• The combination of and the type of the two elements determines the connective tissue type– Connective tissue proper– Fluid connective tissue– Supporting connective tissue
Connective Tissue Proper• Many types of cells,
fibers and syrupy ground substance– Fibroblasts
• Large, star-shaped cell that produces fibers by secreting proteins into the matrix
– Macrophages• Function as defensive
cells, clearing foreign particles
– Mast cells• Begin body’s defense
actions after injury or infection
• Matrix– Ground substance
• Syrupy, clear, colorless– Fibers
• Collagen fibers - strong and flexible
• Elastic fibers - stretches, but returns to original length
• Reticular fibers - interwoven network
• Examples– Skin– Fatty tissue– Tendons and
ligaments
Types Connective Tissue Proper• Areolar connective
tissue– Most widely distributed
connective tissue– Soft, pliable tissue
(Cobweb-like)
Types Connective Tissue Proper• Areolar connective
tissue– Most widely distributed
connective tissue– Soft, pliable tissue
(Cobweb-like)– Contains all fiber types
• Can soak up excess fluid• Cusions and protects body
organs• Separates from and
attaches skin to muscles
• Adipose tissue– Matrix is an areolar
tissue • fat globules stored in
cytoplasm
– Many cells contain large lipid deposits
Types Connective Tissue Proper
• Adipose tissue– Matrix is an areolar
tissue • fat globules stored in
cytoplasm
– Many cells contain large lipid deposits
– Functions• Insulates the body• Protects some organs• Serves as a site of
fuel storage
Types Connective Tissue Proper
Types Connective Tissue Proper
• Dense connective tissue– Main matrix element
is collagen fibers closely packed
– Cells are fibroblasts
Types Connective Tissue Proper
• Dense connective tissue– Main matrix element
is collagen fibers closely packed
– Cells are fibroblasts– Examples
• Tendon – attach muscle to bone
• Ligaments – attach bone to bone
• Reticular connective tissue– Delicate network
of interwoven fibers
Types Connective Tissue Proper
• Reticular connective tissue– Delicate network
of interwoven fibers
– Forms stroma (internal supporting network) of lymphoid organs
• Lymph nodes• Spleen and liver• Bone marrow
Types Connective Tissue Proper
Fluid Connective Tissue
• Blood– Blood cells (red,
white, platelets) surrounded by fluid matrix (blood plasma)
– Fibers are visible during clotting
Figure 3.19h
Fluid Connective Tissue
• Blood– Blood cells (red,
white, platelets) surrounded by fluid matrix (blood plasma)
– Fibers are visible during clotting
– Functions as the transport vehicle for materials
Figure 3.19h
Type Supportive Connective Tissue
• Bone (osseous tissue)– Hardest of
connective tissues– Functions
• Used to protect and support the body
• Forms “levers” for movement
• Forms red blood cells
• Stores calcium and phosphorus
Type Supportive Connective Tissue
• Bone (osseous tissue)– Hardest of
connective tissues– Functions
• Used to protect and support the body
• Forms “levers” for movement
• Forms red blood cells
• Stores calcium and phosphorus
– Composed of:• Bone cells (osteocytes) in
lacunae (cavities)• Hard matrix of calcium
phosphate salts• Large numbers of collagen
fibers
• Hyaline cartilage– Most common
cartilage• Found on ends of
bones in joints• Soft part of nose• Supporting rings in
respiratory passages• Entire fetal skeleton
Type Supportive Connective Tissue
• Hyaline cartilage– Most common
cartilage• Found on ends of
bones in joints• Soft part of nose• Supporting rings in
respiratory passages• Entire fetal skeleton
– Composed of:• Abundant, very fine
collagen fibers• Rubbery matrix
Type Supportive Connective Tissue
• Elastic cartilage– Dense network of
elastic fibers– More flexible than
hyaline cartilage
Type Supportive Connective Tissue
• Elastic cartilage– Dense network of
elastic fibers– More flexible than
hyaline cartilage– Provides elasticity and
support– Found
• External ear• Epiglottis• Parts of larynx
Type Supportive Connective Tissue
• Fibrocartilage– Highly compressible
and very tough– Examples
• Cushion-like discs between vertebrae
• Cushions bones in knees and pelvic girdle
Type Supportive Connective Tissue