Human Tissues
BIO 231
Anatomy and Physiology I
Epithelial Tissue
Epithelium
Over entire body
Protective
Most body inner cavities
All be specialized
e.g. - glandular
Characteristics of
Epithelium
1. Cellularity - closely
packed - little extracellular material
2. Special contacts -
tight junctions &
3. Polarity - apical
& basal surfaces
Some
have microvilli
Some
with cilia
Basal lamina -
non-cellular adhesive sheet - mainly glycoproteins
Characteristics of
Epithelium
4. Supported by
connective tissue
Basal lamina and
reticular lamina (collagen) - together these form the basement membrane -
reinforcement for the epithelium
5. Avascular but
innervated
6. Regeneration - capacity via cell division
Classification of
Epithelial Tissue
Simple - single layer
Stratified - two or more
cell layers
Classification of
Epithelial Tissue
Simple Squamous
Epithelium
Flattened out cells
Location
Kidney
glomeruli, lining of the heart & blood vessels, (air sacs) & lining of ventral
body cavity)
Endothelium - lining of
the vessels, heart & lymphatic vessels
Mesothelium - epithelium
of the serous membranes lining the ventral body cavity and covering its organs
Simple Cuboidal
Epithelium-
Cube shaped cells
Location
Glands & their ducts,
kidney tubules & surface of ovaries
Simple Columnar
Epithelium
Column shaped cells
Location
Stomach, ,
small bronchi & uterus
Pseudostratified Columnar
Epithelium
looks like layers but
every cells touched basement membrane
Columnar
Throat, nasal passages,
sinuses, & male genital ducts
Stratified Squamous
Epithelium
Several cell layers
Surface cells flattened
Basal cells metabolically
active - cuboidal or columnar
Stratified Columnar
Epithelium
Transitional - Lining of
urinary organs
Glandular Epithelium
Gland - one or more cells
that make & secrete a particular product
The product is called a
secretion
Classification
Exocrine
- secrete their product into
Endocrine
- secrete their product into blood stream
Exocrine Glands
Exocrine Glands
Connective Tissue
Binds structure together
Support
Protection
Fills Spaces
Stores fat
Forms blood cells
Generally tissue cells
separated by
Connective Tissue
Three main elements
Ground substance
Fibers
Cells
Ground Substance of
Connective Tissue
Fills spaces between
cells - contains the fibers
Composed of
Tissue
Adhesion proteins
Fibronectin,
laminin and others
Proteoglycans
Protein
+ glyscosaminoglycans (stick out like bristles of a bottle brush)
e.g.
chondroitin sulfates & hyaluronic acid
Fibers in Connective
Tissue
Collagen fibers
Appear white, form
bundles
Elastic fibers
Appear yellow
Reticular fibers
Fine fibers
Cells of Connective
Tissue
Undifferentiated cells
-secrete matrix
Connective
tissue proper -
Cartilage
- chrondroblasts in
Bone
- Osteoblasts
Blood
- hematopoietic cells
Mature cells
Indicated
by the suffix cyte
Maintain
the health of the matrix
Other cells
Fat
cells & white blood cells
Types of Connective
Tissue
Mesenchyme
- connective tissue
Loose
Connective Tissue
Types
Areolar, adipose & reticular
Dense
Connective Tissue
Types
Dense regular, dense irregular and elastic
Areolar Connective Tissue
Gel-like matrix
All 3 fiber types
Fibroblasts, macrophages,
mast cells & other white cells
Wraps & cushions organs,
holds tissue fluid , fights infection via macrophages
Adipose Tissue
Very sparse
Packed with adipocytes -
mostly fat droplets
Under skin, around
kidneys & eyeballs, within abdomen and in breasts
Reticular Connective
Tissue
Reticular fibers in loose
ground substance
Supports other cells
Found in organs
Dense Regular Connective
Tissue
Primarily fibers
Tendons, ligaments&
aponeuroses
Dense Irregular
Connective Tissue
Irregular arranged
collagen fibers
Dermis of the skin,
sunmucosa of the digestive tract, fibrous capsules of organs and of joints
Hyaline Cartilage
Amorphous but firm matrix
Chrondrocytes live in
spaces called
Embryonic skeleton,
covers the ends of bones, costal cartilage of ribs & cartilages of the
nose, trachea and larynx
Elastic Cartilage
Similar to hyaline , more
fibers
Supports external ear
& epiglottis
Fibrocartilage
Matrix similar to hyaline
cartilage but less firm, collagen predominates
Strong & can absorb
shock
Intervertebral discs,
pubic & discs of the knee joint
Types of Connective
Tissue
Cartilage
Hyaline
- most common
Milk
glass appearance
Nose.
end of long bones & ribs
Support
rings of
Fetal
skeleton
Types of Connective
Tissue
Elastic
Outer
ear
Fibrocartilage
pads
between vertebrae
wedges
of knee joint
Types of Connective
Tissue
Bone
Compact
bone - shaft of long bones
Osteocytes
in around Haversian canals
Spongy
bone - ends of long bone
Types of Connective
Tissue
Blood
Liquid
matrix- plasma
RBC
WBC
Platelets
Muscle Tissue
Have the capacity to
contract or shorten and then return to their original length
Skeletal
Smooth
Cardiac
Skeletal Muscle
Single cells - muscle
fibers
Elongate &
multinucleate
Show cross striations or
banding
Due contractile proteins
- & myosin
Cause voluntary movement
in the muscles of our bodies
Smooth Muscle
Spindle in shape - No
striations
Contract
Found in hollow organs
such stomach & intestine and also in the walls of blood vessels
Cardiac Muscle
Muscle of the heart
Shows striations
Branched cells
interconnected to each other at electrical junctions called discs
Nervous Tissue
Neurons
Cell body
Dendrites
Axon
Nerves - bundles of axons
Glial cells - cells of the nervous system