Chapter 4 Flashcards
Epithelial Tissue Functions
Protection Secretion Absorption Diffusion Filtration Sensory Reception
Epithelial Tissue Characteristics
Cellular Specialized cell junctions Polar Supported by Connective Tissue Avascular but innervated Regenerative
Tight Junctions
Barrier; Prevent movement across tissues
Desmosomes
Anchor cells together and act as an adhesive against mechanical forces
Gap Junctions
Serve as a direct passageway between cells to share contents
Basal Lamina
Non cellular sheet that acts as a selective filter
Basement membrane
Reticular fibers and basal lamina; bind epithelium to underlying tissue
Microvilli
Projections that maximize surface area, especially in absorbative tissue
Cilia
Whiplike, mobile extensions that aid in movement of substances across surfaces
Simple Squamous
1 layer of flat cells
Allows for diffusion and filtration; Secretes in serosa
Location: Kidney, Alveoli, Lining of heart and blood vessels and lymph vessels and ventral cavity
Simple epithelia
1 layer
Used for diffusion, secretion, and absorption
Stratified epithelia
Multiple layers
Used for protection
Simple Cuboidal
1 layer of cube cells
Function in secretion and absorption
Location- Kidney tubules, ducts, and secretory portions of small glands, ovary surface
Simple columnar
1 layer of tall cells
Function- Absorption, secretion of mucus and enzymes, propels mucus
Location-
Nonciliated- GI tract, gallbladder, and excretory ducts
Ciliated- Small bronchi, uterine tubes, uterus
Pseudostratified ciliated columnar
1 irregular layer of tall cells
Function- secretion of mucus and ciliary propulsion
Location- Male sperm ducts and large glands; Trachea and upper respiratory tract
Stratified squamous
Top- Flat & Bottom- Cuboidal Function- Protection from abrasion Location- Non-Keratinized- Esophagus, mouth, and vagina Keratinized- Epidermis
Stratified cuboidal
2 layers of cube cells
Function in protection
Location- Largest ducts of mammary, sweat, and salivary glands
Stratified columnar
Top- Tall & Base- Cube
Function- Protection and secretion
Location- Male urethra and large ducts
Transitional Epithelium
Cell shape changes based on stretch
Found in the ureters, bladder, and urethra
Stretched readily
Connective Tissue Characteristics
Few cells, lots of matrix
Extracellular matrix made of ground substance and fibers
Derived from mesenchyme
Collagen Fibers
Strong and abundant; Resist tension and provide strength
Reticular Fibers
Provide support with slight give
Elastic fibers
Stretch and recoil
Proper Loose Connective Tissues
Areolar- Model connective tissue
Adipose- Primarily fat and nutrient storage
Reticular- Support in lymph and spleen
Proper Dense Connective Tissue
Regular- Tendons, Ligaments, and Aponeuroses
Irregular- Resist tension from all directions; fibrous joint capsules
Elastic- Walls of arteries, bronchial tubes, ligaments of vertebral column
Cartilage Types
Hyaline- Embryonic skeleton, end of bones, costal cartilage, nose, trachea, and larynx
Elastic- External ear and epiglottis
Fibrocartilage- Intervertebral discs, pubic symphysis, and discs of knee joints
