Download INTEGUMENTARY SYSTEM - Orange Coast College

HISTOLOGY
THE STUDY OF TISSUES
GENERAL
Tissue = Cells with similar structure &
function organized into groups or layers
Four major types:
- Epithelial (Covers or lines surfaces, found
in glands)
- Connective (Bind & support body parts)
- Muscle (Movement)
- Nervous (Detect changes & transmit info.)
CHARACTERISTICS OF
EPITHELIAL TISSUE
Covers all body surfaces inside & out
Many tightly packed cells, usually
arranged into layers
Free surface & basement membrane
Functions: protection, absorption,
sensation, secretion
High rate of cell division (healing)
Avascular (rely on diffusion)
Epithelial Cell Surface
CLASSIFICATION OF
EPITHELIAL TISSUE
 Layers
- Simple (one layer)
- Stratified (>1 layer; Note: only cells at
surface have characteristic shape)
 Shapes
- Squamous
- Cuboidal
- Columnar
- Transitional
CONNECTIVE TISSUE GENERAL
Few cells widely spaced in non-living
matrix
Matrix may be solid, semi-solid, fluid
Largest % of tissue by weight; found in all
body parts
Binds, protects, supports
May be vascular
CONNECTIVE TISSUE GENERAL
Fibroblast
- Most common cell
- Secretes fibers
* Collagen – strong, flexible, structural
* Elastic – stretch & recoil
* Reticular – highly branched, supportive
Differs in type & amount of fibers in
matrix
Loose or dense; regular or irregular
MUSCLE TISSUE
Contract, provide movement
3 types:
- Skeletal (attached to bones)
- Smooth (hollow organs)
- Cardiac (heart)
NERVOUS TISSUE
Regulate, coordinate, body functions
Brain, spinal cord, nerves
2 types of cells:
- Neuron (nerve cell)
* Most specialized cell in body
* Conducts (Transmission of nerve
impulse)
- Neuroglia (“nerve glue”)
* Assist neurons (bind, protect, supply)