Tissues:
The living
fabric
Ch 4 b
Connective Tissue
First
Let’s review Epithelial tissue
What type is this?
Simple cuboidal epithelium
What type is this?
Simple cuboidal epithelium
What type is this?
Transitional epithelium
What type is this?
Transitional epithelium
What type is this?
Pseudostratified epithelium
Pseudostratified epithelium
What is this
called?
Pseudostratified epithelium
What is this
called?
Cilia!
What type is this?
Stratified squamous epithelium
What
tissue is
this?
What type is this?
Simple columnar epithelial tissue
Connective
Tissue
Connective Tissue
• Found throughout the
body
• Most abundant and most
widely distributed
Connective Tissue
• Four Main classes
–Connective tissue proper
•Includes fat and fibrous
tissue of ligaments
–Cartilage
–Bone
–Blood
Functions of Connective
Tissue
• Binding and support
• Protection
• Insulation
• Transportation
–blood
Characteristics of
Connective Tissue
• Connective tissues have:
–Common origin
•Arise from Mesenchyme (an
embryonic tissue)
–Varying degrees of vascularity
•From avascular to rich in
blood vessels
Characteristics of
Connective Tissue
• Has large amounts of
nonliving extracellular
matrix, consisting of ground
substance and fibers
Structural Elements of
Connective Tissue
• Has 3 main elements:
• 1. Ground substance –
unstructured material that fills
the space between cells
• 2. Fibers – collagen, elastic, or
reticular
Structural Elements of
Connective Tissue
• Has 3 main elements:
• 3. Cells – fibroblasts,
chondroblasts, osteoblasts, and
hematopoietic stem cells
Structural Elements of
Connective Tissue
• Ground substance and fibers
make up the matrix
Ground Substance
• Functions as a molecular sieve
through which nutrients diffuse
between blood capillaries and cells
Proteoglycan
Structure
Ground Substance
• Composed of:
–Interstitial (tissue) fluid
–Adhesion proteins– serves as
the glue
–Proteoglycans – (protein core
with glycosaminoglycans
(GAGs) attached
•Traps water
Fibers – 3 types
• Collagen –
–Strongest, most abundant;
–tough and provides high
tensile strength
–(stronger than steel fibers
the same size)
–Glistening white
appearance – called white
fibers
Fibers
• Elastic –
–long, thin fibers
–form branching network
–allows for stretch
–Contains rubber-like
protein called elastin
–Appear yellow so
sometimes called yellow
fibers
Fibers
• Reticular –
–branched collagenous fibers
–form delicate networks
–Abundant where connective
tissue abuts other tissue types
•Basement membrane of
epithelial
•Form nets around capillaries
Cells
Immature and Mature forms
• Actively mitotic immature cells
that secrete ground substance
and fibers in their particular
matrix
Cells
Immature and Mature forms
• Fibroblasts – connective tissue
proper
• Chondroblasts – cartilage
• Osteoblasts – bone
• Hematopoietic stem cells – blood
Cells
• Once matrix is synthesized, the
blast cells mature into less active
cells (indicated by the suffix –
cyte)
• Hematopoietic stem cells are
always actively mitotic
• Other cell types in connective
tissue include White blood cells,
plasma cells, macrophages, and
mast cells
Types of
Connective Tissue
Connective Tissue: Embryonic
• Mesenchyme – embryonic
connective tissue
–Gel-like ground substance
with fibers and star-shaped
mesenchymal cells
–Gives rise to all other
connective tissues
–Found in the embryo
Connective Tissue:
Embryonic
Figure 4.8a
Connective Tissue Proper
• 2 subclasses
• Loose connective tissue
–Areolar, adipose, and
reticular
• Dense connective tissue
–Dense regular, dense
irregular, and elastic
Connective Tissue Proper:
Loose
• Areolar connective tissue
–Gel-like matrix with all three
connective tissue fibers
–Fibroblasts, macrophages, mast
cells, and some white blood cells
–Wraps and cushions organs
–Widely distributed throughout
the body
Areolar Connective Tissue
Figure 4.8b
Connective Tissue Proper:
Loose
• Adipose connective tissue
–Matrix similar to areolar
connective tissue with closely
packed adipocytes (fat cells)
–Reserves food stores, insulates
against heat loss, and supports
and protects
Connective Tissue Proper:
Loose
• Adipose connective tissue
–Found under skin, around
kidneys, within abdomen, and
in breasts
–Local fat deposits serve
nutrient needs of highly active
organs
Connective Tissue Proper:
Loose
• Adipose connective tissue
–Abundant –
–average person 18% of
body weight is adipose
–Chubby person body can be
50% adipose tissue
Adipose
Figure 4.8c
Connective Tissue Proper:
Loose
• Reticular connective tissue
–Loose ground substance with
reticular fibers
–Reticular cells that lie in a
fiber network
–Forms a soft internal skeleton,
or stroma, that supports other
cell types
Connective Tissue Proper:
Loose
• Reticular connective tissue
–Found in lymph nodes, bone
marrow, and the spleen
Reticular Connective Tissue
Figure 4.8d
Connective Tissue Proper:
Dense Regular
• Parallel collagen fibers with a
few elastic fibers
• Major cell type is fibroblasts
• Attaches muscles to bone or
to other muscles, and bone to
bone
• Found in tendons, ligaments,
and aponeuroses
Dense Regular Connective
tissue
Figure 4.8e
Connective Tissue Proper:
Dense Irregular
• Irregularly arranged collagen
fibers with some elastic fibers
• Major cell type is fibroblasts
• Withstands tension in many
directions providing
structural strength
Connective Tissue Proper:
Dense Irregular
• Found in the dermis,
submucosa of the digestive
tract, and fibrous organ
capsules
Dense Irregular
Figure 4.8f
Cartilage
• Stands up to tension and
compression
• Tough but flexible
• Lacks nerve fibers
• Avascular
• Cartilage matrix is up to 80%
water
• Heals very slowly
Cartilage
• 3 types –
–hyaline
–elastic
–fibrocartilage
Connective Tissue: Hyaline
Cartilage
• Most abundant
• Glassy blue white appearance
• Supports, reinforces, cushions,
and resists compression
• Forms the costal cartilage
• Found in embryonic skeleton,
the end of long bones, nose,
trachea, and larynx
Connective Tissue: Hyaline
Cartilage
Figure 4.8g
Connective Tissue: Elastic
Cartilage
• Similar to hyaline cartilage but
with more elastic fibers
• Maintains shape and structure
while allowing flexibility
• Supports external ear (pinna)
and the epiglottis
Connective Tissue: Elastic
Cartilage
• Similar to hyaline cartilage but with more
elastic fibers
• Maintains shape and structure while
allowing flexibility
• Supports external ear (pinna) and the
epiglottis
Figure 4.8h
Connective Tissue:
Fibrocartilage Cartilage
• Matrix similar to hyaline
cartilage but less firm with thick
collagen fibers
• Provides tensile strength and
absorbs compression shock
• Found in intervertebral discs,
the pubic symphysis, and in discs
of the knee joint
Fibrocartilage Cartilage
• Matrix similar to hyaline cartilage but less
firm with thick collagen fibers
• Provides tensile strength and absorbs
compression shock
• Found in intervertebral discs, the pubic
symphysis, and in discs of the knee joint
Figure 4.8i
Connective Tissue: Bone
(Osseous Tissue)
• Hard, calcified matrix with
collagen fibers found in bone
• Osteocytes are found in lacunae
and are well vascularized
• Supports, protects, and provides
levers for muscular action
Connective Tissue: Bone
(Osseous Tissue)
• Stores calcium, minerals, and
fat
• Marrow inside bones is the site
of hematopoiesis (blood
formation)
Bone (Osseous Tissue)
Figure 4.8j
Connective Tissue: Blood
• Red and white cells in a fluid
matrix (plasma)
• Contained within blood
vessels
• Functions in the transport of
respiratory gases, nutrients,
and wastes
Connective Tissue: Blood
Figure 4.8k
What kind is this?
Areolar Connective Tissue
What kind is this?
Areolar
What kind is this?
Reticular Connective tissue
What kind is this?
Reticular connective tissue
What kind is this?
Reticular connective tissue
What kind is this?
Bone or Osseous tissue
What kind is this?
Bone (osseous) tissue
What kind is this?
Elastic Cartilage
What kind is this?
Fibrocartilage
What kind is this?
Hyaline Cartilage
What kind is this?
Adipose (fat)
What kind is this?
Adipose (fat)
What kind is this?
Adipose (fat)
What kind is this?
Blood
What kind is this?
Blood
What kind is this?
Blood
What kind is this?
Dense Regular connective
What kind is this?
Dense Regular connective
What kind is this?
Dense Irregular connective
Quiz – Next
time!
I will be checking
study guides pages
8-16