A patient presents with severe digestive abnormalities. Upon initial examination, CBC ruled out infection and X-rays revealed no bowel obstructions. Doctors begin to suspect problems within the enzymes, mainly from the liver. How do you proceed to diagnose?

Terminology Tissues – group of cells that carry out specialized activities – Histo = Tissue -ology = study of Pathologists – Study of cells and tissue; diseased – Patho = disease

Four Main Types Epithelial – Body surfaces, hollow organs, glands Connective – Binds organs together, energy reserves for fat Muscle – Movement and force application Nervous – Stimulates action potential to activate body functions

Ectoderm – N ervous system and the epidermis of skin Mesoderm – C onnective tissue, blood, muscles Endoderm – GI tract, Bladder, and Respiratory tract

1. Covering and Lining 2. Glandular Epithelium Functions : Protection, Filtration, Secretion, Absorption, and Excretion Divisions:

Exposed to body cavity Attachment between Epithelial and Connective Tissue Avascular – NO blood vessels

Cell Junctions – Point of contact between adjacent membranes of various cell types 1.Tight Junctions – Fluid tight seal between cells to prevent leaking of substances into blood or surrounding tissues; stomach lining & urinary bladder, and intestines 2.Anchoring Junction (Desmosomes) – Fasten cells to on another, common in stretched areas such as heart, uterus, and outer skin 3.Gap Junction – Allow passage of chemical/electrical signals through connexons (protein tunnels) from cell to cell; i.e. muscular contraction, pain

Tissue Arrangements Layer Arrangement Simple Single Layer Osmosis, Diffusion, Absorption, Secretion Stratified Two or More layers Protect underlying tissues In areas of wear and tear Pseudostratified One layer of mixed cells Mucus Secretion And Movement

Cell Shapes Squamous Flat Cuboidal Thick Cubed Columnar Tall, Cylindrical Transitional Varies

Simple Squamous Function Function: Filtration, diffusion, osmosis, and secretion in serous membranes Location Location: Kidneys Glomeruli (water, glucose, and wastes), Air Sac of Lungs (Gas Exchange), Heart and Blood Vessels (Nutrients & Medicine)

Simple Cuboidal Function:Function: Secretion and Absorption LocationLocation : Kidney Tubules (Wastes), Ovary Surface (Ova)

Ciliated Simple Columnar FunctionFunction: Moves fluids and particles along passageways LocationLocation: Found in respiratory tract (mucosal Movement), fallopian tubes (Ova movement), sinuses (Pathogen removal  Runny Nose) Cilia

Non-Ciliated Columnar FunctionFunction: Microvilli secretion and Absorption Location:Location: GI tract lining (Absorption of nutrients and water) & Gallbladder (Secretion of Bile)

Pseudostratified Columnar Epithelium Functions Functions: Mucus movement by cilia action Location Location: Found in upper respiratory tract and urethra, and gonads of males (Sperm maturation)

Stratified Squamous Functions: Functions: Protection of superficial layers of skin; vagina, mouth, esophagus, tongue Location: Location: – Keratinized = Superficial Layers of Skin – Non-Keratinized = Wet Surfaces (Mouth, Vagina, Tongue)

Stratified Cuboidal Functions:Functions: Protection and limited secretion of sweat glands LocationLocation: Sudoriferous Glands (SWEAT)

Transitional Epithelium FunctionFunction: Accommodate Distension in the urinary tract and vaginal walls as fluid pressures vary. –Stretched = SquamousRelaxed = Cuboidal LocationLocation: Lining of the ureters, urethra, and bladder

Glandular Epithelium: Endocrine Function:Function: Produce hormones Location:Location: Thyroid, Pituitary Gland, Ovaries,Testicles

Secretion of exocrine glands – Merocrine (or eccrine) secretion Forms the product and discharge from the cell entirely – Salivary Glands – Apocrine secretion Product forms at apical surface and pinches off from rest of cell – Mammary gland – Holocrine secretion Accumulates secretory product in cytosol, cell dies and is discharge with its product – Sebaceous Gland (Acne)