Tissues and the Integumentary System Vocabulary

Vocabulary flashcards generated from lecture notes on tissue classification, histology, and the integumentary system.

Tissue

A group of cells with similar structure and function as well as similar extracellular substances located between the cells.

Histology

The science that deals with the study of tissues.

Pathologist

A physician who examines tissues for changes that may indicate damage or disease.

Endoderm

The inner primary germ layer formed during embryonic development.

Mesoderm

The middle primary germ layer formed during embryonic development.

Ectoderm

The outer primary germ layer formed during embryonic development.

Epithelial Tissue

A primary tissue type that covers body surfaces, forms glands, and lines body cavities, hollow organs, and ducts.

Connective Tissue

The most widespread and varied tissue type that serves to connect, support, bind, or protect organs, store energy, and provide immunity.

Muscular Tissue

A primary tissue type consisting of contractile cells or fibers that generates physical force to produce movement.

Nervous Tissue

A tissue with a high degree of excitability and conductivity that detects changes and transmits nerve impulses to maintain homeostasis.

Squamous Epithelium

Epithelial tissue consisting of thin, flat cells that allow diffusion and filtration.

Cuboidal Epithelium

Epithelial tissue consisting of cube-shaped cells adapted for secretion or absorption.

Columnar Epithelium

Epithelial tissue composed of tall, thin cells adapted for secretion and absorption.

Transitional Epithelium

A specialized stratified epithelium whose cells change shape from cuboidal to squamous to accommodate fluid volume changes in organs like the urinary bladder.

Simple Epithelium

Epithelium consisting of a single layer of cells whose primary function is moving materials through processes such as diffusion, secretion, or filtration.

Pseudostratified Epithelium

Epithelium consisting of a single layer of cells of varying heights whose nuclei positioned at different levels give the false appearance of multiple layers.

Stratified Epithelium

Epithelium consisting of multiple layers of cells primarily adapted for protecting underlying structures against abrasion.

Tight Junctions

Cell junctions that fuse plasma membranes together tightly to prevent substances from passing between adjacent cells.

Adherens Junctions

Cell junctions containing a dense layer of protein called a plaque that forms an adhesion belt to resist separation when stretched.

Gap Junctions

Cell junctions that form open channels allowing ions and small molecules to pass directly between cells for communication and impulse conduction.

Desmosomes

Spot-like cell junctions where a protein plaque binds to intermediate filaments to anchor adjacent cells firmly to one another.

Hemidesmosomes

Junctions resembling half of a desmosome that anchor epithelial cells to the underlying basement membrane.

Endocrine Gland

A ductless gland that secretes chemical messengers called hormones directly into interstitial fluid and the blood.

Exocrine Gland

A gland that secretes its product through a duct onto a body surface or inside a body cavity.

Fibroblasts

Large, flat connective tissue cells that move and secrete fibers and ground substance into the extracellular matrix.

Macrophages

Connective tissue cells derived from white blood cells that engulf bacteria and cellular debris by phagocytosis.

Suffix -blast

A connective tissue cell suffix meaning "germ" that denotes active cells that produce the extracellular matrix.

Suffix -cyte

A connective tissue cell suffix meaning "cell" that denotes mature cells responsible for maintaining the matrix.

Suffix -clast

A connective tissue cell suffix meaning "break" that denotes cells responsible for breaking down matrix for tissue remodeling.

Areolar Connective Tissue

A type of loose connective tissue with a fine network of collagen and elastic fibers that forms the packing tissue beneath epithelia.

Adipose Tissue

A type of loose connective tissue dominated by fat cells (adipocytes) that stores energy, insulates against heat loss, and cushions organs.

Reticular Tissue

Connective tissue consisting of a network of reticular fibers and reticular cells that forms the stroma of the spleen, lymph nodes, and bone marrow.

Chondrocytes

Specialized cartilage-forming cells located in small spaces within the matrix called lacunae.

Hyaline Cartilage

Cartilage with small, evenly dispersed collagen fibers that appears transparent, providing smooth articulating surfaces and flexible support.

Fibrocartilage

Cartilage containing thick, abundant bundles of collagen fibers that enable it to withstand severe compression and pulling forces.

Elastic Cartilage

Cartilage containing coiled elastic fibers within its matrix that allow it to recoil to its original shape after being bent.

Neurons

Nerve cells capable of conducting action potentials to transmit information throughout the nervous system.

Neuroglia

Non-conducting supportive cells in nervous tissue that nourish, protect, and insulate neurons.

Dendrites

Nerve cell processes that receive incoming stimuli and conduct electrical changes toward the cell body.

Axon

A long nerve cell process along which action potentials originate and travel away from the cell body.

Epidermis

The superficial, thinner layer of skin composed of keratinized stratified squamous epithelium.

Dermis

The deeper, thicker layer of skin composed of dense connective tissue that provides structural strength and houses blood vessels, nerves, and glands.

Hypodermis

The subcutaneous tissue deep to the dermis made of loose connective tissue and fat that anchors the skin to underlying organs.

Keratinocytes

The most abundant epidermal cells (~90%) that synthesize the protective protein keratin and lamellar granules.

Melanocytes

Epidermal cells (~5%) located in the stratum basale that produce the pigment melanin to protect against UV radiation.

Langerhans Cells

Epidermal cells that participate in immune responses against microbial pathogens that invade the skin.

Merkel Cells

Epidermal cells in the stratum basale that contact tactile discs of sensory neurons to detect light touch sensations.

Stratum Basale

The deepest layer of the epidermis consisting of a single row of cuboidal or columnar stem cells undergoing active mitotic division.

Stratum Corneum

The most superficial layer of the epidermis consisting of 25 to 30 layers of dead, flattened, keratin-filled squamous cells.

Meissner Corpuscles

Cutaneous nerve endings located in dermal papillae responsible for sensing light touch, fine texture, and low-frequency vibrations.

Pacinian Corpuscles

Sensory nerve endings located in the reticular dermis and subcutaneous layer that detect deep pressure and high-frequency vibrations.

Cyanosis

A bluish discoloration of the skin resulting from reduced oxygen saturation in the blood.

Arrector Pili

Bundles of smooth muscle cells attached to hair follicles that contract during cold or fright to pull hair shafts erect.

Sebaceous Glands

Exocrine glands in the dermis that secrete an oily substance called sebum into hair follicles or onto skin to soften skin and prevent water loss.

Eccrine Glands

Abundant, widespread sweat glands that produce a clear, watery secretion primarily involved in evaporative cooling.

Apocrine Glands

Sweat glands in the axillary and pubic regions that secrete a thicker sweat in response to emotional stress and sexual stimulation.

Lunula

The whitish, crescent-shaped region at the proximal base of the nail body where the nail matrix is thick.

Rule of Nines

A clinical estimation system that divides total body surface area into regions equal to 9% or multiples of 9% to assess burn severity.