Histology Flashcards

Which epithelial type lines the urinary bladder and can change shape with distension?

Answer: Transitional (urothelium)

Transitional epithelium (urothelium) is unique to the urinary tract and flattens as the bladder fills.

Goblet cells secrete mucus and are scattered among which epithelial cell type in the small intestine?

Answer: Simple columnar absorptive cells

The small intestinal lining is simple columnar epithelium interspersed with mucus-secreting goblet cells.

Reticular fibers, which form the scaffolding of lymph nodes and the liver, are composed primarily of which collagen type?

Answer: Type III collagen

Reticular fibers are thin Type III collagen fibers that stain with silver and support hematopoietic and lymphoid organs.

Which connective tissue is characterized by irregularly arranged collagen bundles and is found in the dermis of the skin?

Answer: Dense irregular connective tissue

Dense irregular connective tissue has randomly oriented collagen bundles that resist tension from multiple directions, as in the dermis.

Mast cells degranulate in response to IgE-mediated stimuli, releasing which primary vasoactive mediator?

Answer: Histamine

Mast cell granules are packed with histamine, which causes vasodilation and increased vascular permeability during allergic reactions.

The esophagus is lined by which epithelial type that protects against abrasion from food?

Answer: Non-keratinized stratified squamous

The esophagus has non-keratinized stratified squamous epithelium, providing abrasion resistance without the dryness of true keratinization.

Pseudostratified ciliated columnar epithelium with goblet cells is the hallmark lining of which anatomical region?

Answer: Trachea and primary bronchi

The respiratory tract (trachea and bronchi) is lined by pseudostratified ciliated columnar epithelium that moves mucus via the mucociliary escalator.