Honors Anatomy and Physiology: Anatomical Organization, Histology, and Tissue Classification

Comprehensive vocabulary flashcards covering cellular diversity, epithelial tissue classifications and glandular secretions, and connective tissue structure from Unit 2 Honors Anatomy and Physiology notes.

Histology

The study of tissues, which encompass epithelial, connective, muscle, and nervous tissues.

Tissue

A group of specialized cells that perform a specific function.

Fibroblast

A cell type that connects body parts, characterized by an abundant rough endoplasmic reticulum and Golgi apparatus.

Erythrocyte

A cell that connects body parts and lacks organelles, containing intermediate filaments.

Macrophage

A disease-fighting cell characterized by pseudopods and abundant lysosomes.

Apical Surface

The upper surface of epithelial tissue that is free or exposed to the outside of the body or to an internal body cavity.

Basal Surface

The lower surface of epithelial tissue that rests on underlying connective tissue.

Basement Membrane

A structure that forms between epithelial tissue and connective tissue.

Avascular

A characteristic of epithelial tissue meaning it lacks its own blood supply; nutrients must diffuse from neighboring connective tissue.

Microvilli

Cellular projections that form a brush border on the apical surface of simple columnar cells (e.g., in the intestinal and digestive tract) to increase surface area for absorption.

Cilia

Protein strands on the apical surface of epithelial cells that engage in coordinated brushing to move materials across the surface, such as in the respiratory tract.

Simple Squamous Epithelium

A single layer of thin, flattened cells commonly located in alveoli and the lining of blood vessels.

Simple Cuboidal Epithelium

A single layer of cube-shaped cells with a centrally located nucleus, commonly found lining kidney tubules.

Ciliated Simple Columnar Epithelium

A single layer of column-shaped cells with cilia, located in the oviducts and upper respiratory tract, which may contain mucus-secreting goblet cells.

Nonciliated Simple Columnar Epithelium

A single layer of column-shaped cells with apical microvilli (brush border), located in the ileum, gallbladder, duodenum, and urinary tract to enhance absorption.

Keratinized Stratified Squamous Epithelium

A multilayered epithelial tissue forming the superficial layer of the skin; cells accumulate keratin filaments as they age, becoming tough and water-resistant.

Non-keratinized Stratified Squamous Epithelium

A multilayered epithelial tissue lacking keratin that must remain moist, found lining the esophagus, oral cavity, vagina, and anal canal.

Stratified Cuboidal Epithelium

An epithelial tissue composed of multiple layers of cube-shaped cells, located in the ducts of mammary, sweat, and salivary glands.

Stratified Columnar Epithelium

A rare type of epithelial tissue composed of multiple layers of column-shaped cells, found in the lining of developing ovarian follicles.

Ciliated Pseudostratified Columnar Epithelium

A single layer of column-shaped cells that appears stratified because nuclei are positioned at different levels; contains cilia to move materials and lines respiratory passages.

Nonciliated Pseudostratified Columnar Epithelium

Pseudostratified epithelial tissue devoid of mucus and cilia, found lining the prostate and vas deferens.

Transitional Epithelium

A specialized epithelial tissue in the urinary bladder whose cells change shape (from squamous to columnar) as body organs stretch and move.

Endocrine Glands

Ductless glands whose secretions (hormones) enter extracellular fluid and diffuse directly into the bloodstream; includes the adrenal, thyroid, and pituitary glands.

Exocrine Glands

Hollow glands lined by glandular epithelium that secrete products into a duct leading to the skin surface or the lumen of a hollow organ; includes sweat and salivary glands.

Merocrine Gland

An exocrine gland whose cells secrete substances by exocytosis through vesicles into a duct, as seen in salivary and sudoriferous (sweat) glands.

Apocrine Gland

An exocrine gland in which a portion of the cell membrane containing secretory products pinches and buds off into the duct, found in mammary and ceruminous glands.

Holocrine Gland

An exocrine gland in which the entire cell disintegrates to release its accumulated secretory contents, as seen in sebaceous (oil) glands.

Connective Tissue

The most abundant body tissue, derived from embryonic mesoderm, which binds, supports, strengthens, insulates, transports (blood), and stores energy (adipose).

Mesenchymal Connective Tissue

The first connective tissue to develop in the embryo from the mesodermal layer, giving rise to all other connective tissues and providing stem cell clusters in adults for tissue repair.

Extracellular Matrix

Material located in the space between connective tissue cells, consisting of ground substance and protein fibers produced by the embedded cells.

Ground Substance

The non-fibrous component of the extracellular matrix that can be fluid, semi-fluid, gelatinous, or calcified.

Collagen Fibers

Extracellular protein fibers made of collagen that are very strong and flexible, found in bones, cartilage, tendons, ligaments, and skin.

Elastic Fibers

Protein fibers containing elastin that provide stretch and recoil properties, located in the skin, blood vessels, and lung tissue.

Reticular Fibers

Extracellular protein fibers composed of collagen with a glycoprotein coating that form a supportive framework for soft organs such as the spleen.