Download Lecture 8- Epithelial- Proper Connective

Tissues
Lecture 8: Epithelial – Proper Connective Tissue
Honors Human Biology /TRCC-­‐K175
Differentiation & Specialization of Cells
Tissues:
-an aggregate of particular types of cells
-form one of the structural materials of a plant or an animal
-all tissue cells are of similar embryonic origin
-working together tissue cells perform specific functions
-protection, support, circulation, growth,
and reproduction
Histology
-study of tissues
Animal Tissue Types
1) Epithelial Tissue
2) Connective Tissue
3) Muscle Tissue
4) Nervous Tissue
Animal Tissue Formation
Gametes-->Zygote-->Embryo
-cells within embryo arranged into 3 tissues
1) Ectoderm
-skin & nervous system
2) Mesoderm
-muscle, skeleton, & the organs of
circulation, reproductive & excretion
3) Endoderm
-lining of the gut and associated organs
Epithelial Tissue
•
protection, secretion, & absorption
•
linked tightly together; one or more layers
•
one “free” surface (may have cilia) & the
other surface adheres to a non-cellular
“basement” membrane
Types of Epithelial Tissue- (Shape)
Three Cell Shapes
1) Squamous - irregular shaped
2) Cuboidal - little boxes or
cubes
3) Columnar - tall, rectangular
shape
Types of Epithelial Tissue
(Arrangement)
1)
Epithelial
-one cell layer thick
2) Stratified Epithelial
-several cells thick
3) Pseudostratified Epithelial
-appear to be layered but are one
layer
4) Transitional Epithelial
-layers of closely packed cells
-soft & pliable easily stretched
Connective Tissue
-contain cells & fibers (collagen
&/or elastin)
-bind structures together, support,
protection, store fat, produce blood
cells, fill spaces, and act as
framework
-connective tissue cells are widely
separated by a non-cellular matrix
Three Major Cell Types in
Connective Tissue
Three Major Cell Types
1) Fibroblasts
- most common
- large star-shaped cells
- produce collagen (white fibers) &
elastin (yellow fibers)
2) Mast Cells
- located near blood vessels
- contain heparin & histamine
3) Macrophages (histiocytes)
- often attached to fibers
- play key role in immunity
Overview of Connective
Tissue in the Human Body
Connective Tissue
Proper
Loose (fibrous) Tissue
1) Areolar Tissue
-joins tissue layers together & holds
organs in place
-mainly composed of fibroblasts
(adult stem cells)
Areolar connective tissue
• Widely distributed; found under skin,
around organs, between muscles
• Wraps and cushions organs
Connective Tissue
Proper
Loose (fibrous) Tissue
2) Adipose Tissue
-specialized loose connective tissue
in which fibroblasts enlarge &
store fat intercellular matrix is
reduced
Adipose (fat) tissue
• Found under skin, around kidneys
and heart
• Functions in energy storage and insulation;
cushioning for organs
-protective cushion for internal
organs
-insulating layer beneath the skin
Connective Tissue
Proper
Loose (fibrous) Tissue
3) Reticular Tissue
-thin delicate fibers
-form the framework of liver, spleen,
bone marrow, and lymph nodes
-give rise to macrophages
Connective
Tissue Proper
Dense (fibrous)
Tissue
4) Dense Connective Tissue
-close packed fibers, mainly collagen
- Found in tendons (connect
muscles to bone) and ligaments
(connect bone to bone)
Dense connective tissue
• Found in tendons and ligaments
• Forms strong bands that attach
bone to muscle or bone to bone
- poor blood supply