Anatomy and Physiology Chapter 5: The Tissue Level of Organization

Flashcards covering core tissue types, cellular connections, epithelial classifications, connective tissues, muscle tissue, nervous tissue, membranes, and tissue repair concepts from Chapter 5.

Histology

The microscopic study of the appearance, function, and organization of tissues.

Pathology

The study of structural and functional changes in tissues that occur with disease.

Tissue

A group of cells that function together to perform a specific task in the body.

Epithelial Tissue

One of the four primary tissue types that forms body coverings, organ linings, and glands.

Connective Tissue

One of the four primary tissue types that provides structural protection, support, and integration of body components.

Muscle Tissue

One of the four primary tissue types composed of contractile cells that provide physical movement.

Nervous Tissue

One of the four primary tissue types composed of neurons and glial cells that allows internal and external communication.

Extracellular Matrix (ECM)

The non-cellular material found outside of tissue cells, composed of ground substance and protein fibers.

Collagen Fibers

Tough, protective, and unbranched protein fibers that represent the strongest fiber type in connective tissue.

Proteoglycans

Negatively charged protein/carbohydrate molecules found within the extracellular matrix.

Tight Junctions

Intercellular connections that fuse the cell membranes of adjacent cells, allowing no movement of substances between cells.

Desmosomes

Strong, flexible intercellular connections that hold cells together while allowing limited movement of substances between them.

Gap Junctions

Intercellular passageways that form channels between cells to allow the movement of specific ions and small molecules.

Hemidesmosomes

Cellular connections that anchor epithelial cells to the underlying extracellular matrix and basement membrane.

Cellular Connections

Specialized structures that attach adjacent cells to one another or to the surrounding extracellular matrix.

Basal Surface

The attached bottom surface of epithelial tissue anchored to the basement membrane.

Apical Surface

The unattached top surface of epithelial tissue exposed to the external environment or an internal body space.

Cilia

Hair-like extensions on the apical surface of epithelial cells that beat synchronously to move materials across the cell surface.

Microvilli

Folded membrane extensions on the apical surface of epithelial cells that increase surface area for absorption.

Squamous Cells

Flat, thin epithelial cells.

Cuboidal Cells

Box-shaped or cube-like epithelial cells.

Columnar Cells

Tall, column-like epithelial cells.

Simple Epithelium

An epithelial tissue consisting of a single layer of cells.

Stratified Epithelium

An epithelial tissue consisting of two or more layers of cells.

Pseudostratified Columnar Epithelium

An epithelial tissue consisting of a single layer of cells of differing heights that appears stratified, where every cell touches the basement membrane.

Transitional Epithelium

A stratified epithelial tissue whose cells stretch and change shape, allowing urinary organs like the bladder to expand.

Goblet Cells

Unicellular glands found in simple and pseudostratified epithelia that secrete mucus.

Simple Squamous Epithelium

A single layer of flat cells found in air sacs of lungs and blood vessel linings that allows diffusion and filtration.

Endocrine Glands

Ductless glands that secrete hormones directly into the blood or interstitial fluid.

Exocrine Glands

Glands that secrete substances locally onto an epithelial surface through a duct.

Merocrine Secretion

A mode of exocrine secretion accomplished entirely through exocytosis.

Apocrine Secretion

A mode of exocrine secretion where secretory material accumulates near the apical surface of the cell before pinching off.

Holocrine Secretion

A mode of exocrine secretion involving the rupture and destruction of the entire gland cell to release its product.

Fibroblasts

Connective tissue cells that produce protein fibers and ground substance for the extracellular matrix.

Elastic Fibers

Connective tissue fibers containing elastin that provide flexibility and stretchiness.

Reticular Fibers

Thin, branching protein fibers that form a supportive network within internal soft organs.

Adipocytes

Connective tissue cells specialized for fat storage, thermal insulation, and organ protection.

Areolar Connective Tissue

A loose connective tissue in the subcutaneous layer that supports surrounding tissues and lies beneath most epithelial layers.

Adipose Tissue

A loose connective tissue consisting mainly of fat-storing cells, serving function in energy storage and cushioning.

Reticular Connective Tissue

A loose connective tissue forming the structural framework of internal organs like the spleen, liver, and lymphatic tissues.

Dense Regular Connective Tissue

A dense connective tissue containing collagen fibers aligned parallel to each other, allowing tissue to withstand force in a single direction in tendons and ligaments.

Dense Irregular Connective Tissue

A dense connective tissue containing collagen fibers oriented in multiple directions, allowing tissue to withstand tensile forces in any plane in the dermis.

Hyaline Cartilage

The most abundant type of cartilage in the body, located within joints and ribs.

Fibrocartilage

The strongest cartilage type containing thick collagen fibers, located in intervertebral discs.

Elastic Cartilage

The most flexible type of cartilage containing abundant elastic fibers, located in the external ear.

Perichondrium

A layer of dense irregular connective tissue that encapsulates cartilage structures in the body.

Compact Bone

Solid bone tissue that provides high strength and protection for internal organs.

Spongy Bone

Lattice-like bone tissue whose interior spaces contain red bone marrow.

Lymph

A fluid connective tissue that is primarily acellular and transports cells and molecules.

Skeletal Muscle

Voluntary, striated muscle tissue containing multinucleated cells attached to bones to move the body.

Cardiac Muscle

Involuntary, striated muscle tissue found in the heart wall, containing branched cells joined by intercalated discs.

Smooth Muscle

Involuntary, non-striated muscle tissue composed of spindle-shaped cells found in the walls of hollow organs and blood vessels.

Neurons

Nervous tissue cells that generate and propagate action potentials to communicate with other cells.

Glial Cells

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

Dendrites

Short neuronal extensions that receive incoming chemical or electrical signals from other cells.

Axon

A long projection extending from a neuron's cell body that transmits outgoing electrical action potentials.

Mucous Membranes

Tissue membranes lining body cavities open to the external environment, such as the digestive and respiratory tracts.

Serous Membranes

Tissue membranes lining internal body cavities and covering organs to reduce friction during movement.

Cutaneous Membrane

The skin, consisting of stratified squamous epithelium and connective tissue, which protects against desiccation and pathogens.

Synovial Membrane

Tissue membrane lining freely movable joint cavities that secretes synovial fluid to lubricate joint cartilage.

Granulation Tissue

A rapidly formed layer of temporary connective tissue during wound repair that acts as a base for migrating epithelial cells.