Epithelial and Connective Tissue Functions, Types, and Repair Processes

Protection

Stratified squamous epithelium found in skin, mouth, esophagus, vagina

Diffusion

Simple squamous epithelium found in lung alveoli

Filtration

Simple squamous epithelium found in kidney glomeruli and endothelium (blood vessel lining)

Absorption

Simple cuboidal epithelium found in kidney tubules; simple columnar epithelium found in intestinal lining

Secretion

Simple cuboidal epithelium found in exocrine glands

Propulsion of mucus

Pseudostratified columnar epithelium found in trachea

Stretch

Transitional epithelium found in the urinary system/bladder

Loose Connective Tissue

Areolar tissue supports epithelia, organs; defends against infection

Adipose Tissue

Stores nutrients, cushions, and insulates

Reticular Tissue

Immune function; home of many white blood cells

Dense Regular Connective Tissue

Binds and supports; resists stretch in one direction

Dense Irregular Connective Tissue

Resists stretch in any direction; encapsulates joints

Elastic Connective Tissue

Strong with elastic recoil; found in walls of large arteries

Fibroblast

Primary cell type in connective tissue proper

Chondrocytes

Primary cell type in cartilage

Osteocytes, Osteoblasts, Osteoclasts

Primary cell types in bone

Collagen

Predominant type of fiber in the extracellular matrix of connective tissues

Ground Substance in Connective Tissue Proper

Pliable proteoglycans that make the tissue highly hydrated and soft

Ground Substance in Cartilage

Rigid matrix of proteoglycans that allows cartilage to resist compression

Ground Substance in Bone

Hard, rigid matrix of calcium phosphate called hydroxyapatite

Skeletal Muscle

Attached to bones, voluntary, striated, long cylindrical cells

Smooth Muscle

Found in walls of hollow organs, involuntary, no striations

Cardiac Muscle

Found in wall of the heart, involuntary, short branched cells

Adenomas and Carcinomas

Types of cancers arising from epithelial tissues

Tissue Repair Process

Inflammation, organization, regeneration, and fibrosis

Inflammation in Tissue Repair

Leaky blood vessels release plasma proteins, leading to coagulation and enhanced inflammation

Granulation Tissue

New tissue that bridges the injury site during tissue repair

Fibrosis

Process of scarring in non-regenerative tissues like heart muscle