Epithelial, Connective, Muscle, and Nervous Tissues

Flashcards generated from lecture notes covering epithelial, connective, muscle, and nervous tissue vocabulary terms, structural components, cell types, and locations.

Free surface

The exposed or outside surface of epithelial tissue.

Basement membrane

The layer underneath epithelial cells that attaches them to underlying tissue.

Avascular

Lacking blood vessels, a characteristic feature of epithelial tissues.

Squamous

Epithelial cell shape that is flat or thin.

Cuboidal

Epithelial cell shape that is cube-shaped.

Columnar

Epithelial cell shape that is tall or elongated.

Simple epithelium

An epithelial tissue arrangement consisting of a single layer of cells.

Stratified epithelium

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

Pseudostratified epithelium

Epithelial tissue that appears to have multiple layers due to nuclei at different levels, but is actually a single layer of cells.

Simple squamous epithelium

A single layer of thin, flat cells specialized for diffusion and filtration, found in alveoli, capillaries, blood vessels, and lymphatic vessels.

Simple cuboidal epithelium

A single layer of cube-shaped cells specialized for secretion and absorption, located in kidney tubules, thyroid follicles, ducts of some glands, and ovaries.

Simple columnar epithelium

A single layer of tall cells with nuclei near the basement membrane, specialized for secretion and absorption in the uterus, stomach, and intestines.

Goblet cells

Specialized epithelial cells that produce and secrete mucus.

Pseudostratified columnar epithelium

A single layer of cells reaching the basement membrane with nuclei at different levels, often possessing cilia and goblet cells to protect respiratory passageways from infection.

Stratified squamous epithelium

Tissue with many cell layers, featuring flat cells at the free surface and cuboidal cells in deeper layers, specialized for protection in the oral cavity, vagina, anal canal, and epidermis.

Epidermis

The keratinized outer layer of the skin composed of stratified squamous epithelium.

Stratified cuboidal epithelium

Tissue consisting of 2 to 3 layers of cube-shaped cells providing protection in the ducts of mammary glands, sweat glands, salivary glands, and the pancreas.

Stratified columnar epithelium

Tissue consisting of several cell layers with tall outer cells and cuboidal deeper cells, found in parts of the male urethra and ducts of exocrine glands.

Transitional epithelium

Also called uroepithelium, tissue containing multiple layers of cuboidal and elongated cells that change shape when stretched to allow organ expansion in the urinary bladder, ureters, and urethra.

Glandular epithelium

Epithelial tissue specialized to produce and secrete substances into ducts or body fluids.

Endocrine glands

Ductless glands that secrete their products directly into tissue fluid or blood.

Exocrine glands

Glands that secrete their products into ducts that open onto internal or external surfaces.

Simple exocrine gland

An exocrine gland possessing an unbranched duct.

Compound exocrine gland

An exocrine gland possessing a branched duct.

Tubular gland

A gland whose secretory portion is structured like a tube.

Alveolar gland

A gland whose terminal secretory portion forms a sac-like dilation.

Merocrine gland

A gland that releases fluid products through exocytosis without losing any portion of the cell.

Apocrine gland

A gland that loses a small portion of its cell bodies during secretion, such as mammary and ceruminous glands.

Holocrine gland

A gland that releases entire cells filled with secretory products during secretion, such as sebaceous glands.

Fibroblasts

Large, star-shaped fixed cells in connective tissue that secrete fibers into the extracellular matrix.

Macrophages

Wandering cells in connective tissue, also known as histiocytes, that carry out phagocytosis to defend against infection.

Phagocytosis

The cellular process of engulfing and destroying harmful particles, damaged cells, or foreign pathogens.

Mast cells

Fixed connective tissue cells that release heparin to prevent blood clotting and histamine to promote inflammation.

Heparin

A compound released by mast cells that helps prevent blood clotting.

Histamine

A chemical released by mast cells that induces an inflammatory response.

Collagen fibers

Thick, strong, flexible, and slightly elastic structural protein fibers made of collagen, heavily found in tendons and ligaments.

Elastic fibers

Stretchy connective tissue fibers made of the protein elastin that allow tissues to stretch and return to their original shape, found in vocal cords and airways.

Reticular fibers

Thin, branching collagenous fibers that form delicate supporting networks in organs such as the liver and spleen.

Areolar connective tissue

A loose connective tissue containing fibroblasts, collagen, elastic fibers, and gel-like ground substance that forms thin membranes and nourishes adjacent epithelium.

Adipocytes

Specialized cells in adipose tissue that store fat droplets, pushing their nuclei to one side.

Adipose tissue

A specialized loose connective tissue composed of adipocytes that provides cushioning, protection, and thermal insulation.

Reticular connective tissue

A network of thin reticular fibers that provides structural support to the walls of internal organs like the liver and spleen.

Dense regular connective tissue

A dense connective tissue containing closely packed, parallel collagen fibers designed to withstand pulling forces in one direction, found in tendons and ligaments.

Dense irregular connective tissue

A connective tissue containing randomly arranged, interwoven collagen fibers capable of withstanding tension from multiple directions, found in the dermis.

Elastic connective tissue

Connective tissue dominated by elastic fibers that can stretch, located in spinal column ligaments, large artery walls, airways, and heart walls.

Chondrocytes

Specialized cartilage cells located within small extracellular chambers called lacunae.

Lacunae

Small chambers or spaces within the matrix of cartilage or bone that enclose chondrocytes or osteocytes.

Perichondrium

A layer of dense connective tissue surrounding cartilage that supplies it with nutrients.

Hyaline cartilage

The most abundant type of cartilage, containing fine collagen fibers in its matrix, located at joint ends of bones, the nose, respiratory passages, and embryonic skeleton.

Elastic cartilage

A flexible type of cartilage containing abundant elastic fibers, located in the external ear and larynx.

Fibrocartilage

A tough, shock-absorbing cartilage packed with dense collagen fibers, found in intervertebral discs, knee menisci, and the pelvic girdle.

Osseous tissue

Bone tissue, the most rigid connective tissue, featuring a matrix of collagen and mineral salts like calcium and phosphorus.

Osteocytes

Mature bone cells situated inside lacunae within bone tissue.

Lamellae

Concentric layers of mineralized bone matrix surrounding a central canal.

Osteon

The fundamental cylindrical unit of compact bone tissue consisting of osteocytes, matrix lamellae, and a central canal.

Central canal

A longitudinal channel running through the center of an osteon containing blood vessels that supply nutrients to compact bone.

Canaliculi

Tiny microscopic channels in bone tissue through which cellular processes of osteocytes extend to communicate and share nutrients.

Spongy bone

Bone tissue located in the interior of bones composed of bony plates separated by marrow-filled spaces.

Plasma

The liquid extracellular matrix of blood in which formed elements are suspended.

Serous membranes

Epithelial membranes lining body cavities that do not open to the outside, composed of simple squamous epithelium and areolar tissue that secrete lubricating serous fluid.

Mucous membranes

Epithelial membranes lining cavities and tubes that open to the outside, containing goblet cells that secrete protective mucus.

Cutaneous membrane

An epithelial membrane that forms the external protective covering of the body, commonly referred to as the skin.

Synovial membranes

Membranes composed entirely of connective tissue that line joint cavities.

Intercalated discs

Specialized intercellular junctions connecting adjacent cells in cardiac muscle tissue.

Soma

The central cell body of a neuron.

Dendrites

Nerve cell structures that function to receive incoming signals and input information.

Axon

A single long process of a neuron that conducts outgoing nerve impulses away from the cell body.

Neuroglia

Specialized cells in nervous tissue that support, nourish, and protect neurons.