Tissue Types, Structure, and Function Flashcards

Vocabulary flashcards covering tissue types, epithelial, connective, muscle, and nervous tissues, including key definitions, locations, structures, and functions from Chapter 4.

Tissue

A group of specialized cells working together to perform one or more functions.

Epithelial tissue

Tissue that covers surfaces, lines cavities and passageways, forms glands, protects, absorbs, secretes, and senses.

Connective tissue

Tissue that supports, binds, protects, stores energy, transports substances, and forms structural frameworks.

Muscle tissue

Tissue that contracts to create movement.

Nervous tissue

Tissue that detects stimuli, processes information, and transmits electrical impulses.

Polarity

A property of epithelial cells where they have distinct surfaces with different structures and functions, featuring an apical top side and a basal bottom side.

Avascular

Lacking blood vessels, requiring nutrients and oxygen to diffuse from blood vessels in underlying connective tissue.

Apical surface

The surface of an epithelial cell that faces the external environment or an internal open space.

Basal surface

The surface of an epithelial cell that attaches to underlying cells or connective tissue, usually by way of a basement membrane.

Microvilli

Epithelial structures that increase surface area, especially for absorption and secretion, found in the small intestine and kidney tubules.

Cilia

Epithelial structures that move substances across the epithelial surface, found in the respiratory tract and uterine tubes.

Cell junctions

Specialized connections between adjacent cells or between a cell and the material beneath it that help cells adhere, communicate, and form barriers.

Gap junctions

Communication junctions that allow ions and small molecules to pass directly between neighboring cells, helping cells coordinate activities.

Tight junctions

Seals formed between adjacent cells that prevent fluids, substances, or pathogens from leaking between cells.

Desmosomes

Strong anchoring junctions that help tissues resist stretching, pulling, and mechanical stress.

Spot desmosomes

Anchoring junctions that attach one cell to another cell at small points.

Hemidesmosomes

Anchoring junctions that attach a cell to the basement membrane rather than to another cell.

Simple squamous epithelium

A single layer of thin, flat cells specialized for diffusion, filtration, secretion, and absorption, located in places like alveoli and blood vessels.

Stratified squamous epithelium

Multiple layers of cells with flat surface cells, specialized primarily for protection against abrasion.

Keratinized stratified squamous epithelium

Epithelium found in the epidermis of skin whose surface cells contain keratin to provide protection and reduce water loss.

Nonkeratinized stratified squamous epithelium

Epithelium found in moist regions (mouth, esophagus, vagina, anus) that protects against abrasion without a dry keratin layer.

Simple cuboidal epithelium

A single layer of cube-shaped cells specialized for secretion and absorption, found in kidney tubules and small glands.

Stratified cuboidal epithelium

Multiple layers of cuboidal cells providing protection and secretion, found in sweat-gland and mammary-gland ducts.

Simple columnar epithelium

A single layer of tall, rectangular cells specialized for absorption, secretion, and sometimes movement by cilia; located in the digestive tract and uterine tubes.

Stratified columnar epithelium

A rare tissue with multiple layers and columnar surface cells that provides protection and secretion in larger ducts and the male urethra.

Pseudostratified columnar epithelium

A single layer of columnar cells with nuclei at different levels that appears multilayered and functions in secretion and movement of mucus/material in the respiratory tract.

Transitional epithelium

A stratified tissue whose cells change shape with stretching to allow repeated expansion in the urinary bladder, ureters, and proximal urethra.

Gland

A single epithelial cell or group of epithelial cells specialized to produce and release a secretion.

Endocrine gland

A ductless gland that releases hormones into interstitial fluid and then into the bloodstream.

Exocrine gland

A gland that releases secretions through ducts onto a surface or into a body cavity or lumen.

Goblet cells

Cells that produce mucin, which mixes with water to form protective, lubricating mucus.

Merocrine secretion

A secretion method where the secretory product leaves by exocytosis and the cell remains intact (e.g., salivary glands).

Apocrine secretion

A secretion method where the apical part of the cell pinches off along with the secretion (e.g., mammary glands, some sweat glands).

Holocrine secretion

A secretion method where the entire cell ruptures and dies, causing the cell contents to become the secretion (e.g., sebaceous glands).

Connective-tissue matrix

The extracellular material consisting of protein fibers and ground substance in which connective tissue cells are embedded.

Fibroblasts

Active cells in connective tissue that produce protein fibers and ground substance, plays an important role in tissue repair.

Fibrocytes

Mature, less-active connective tissue cells that maintain the matrix.

Mesenchymal cells

Stem cells in connective tissue that can divide and differentiate into fibroblasts and other connective-tissue cells.

Melanocytes

Connective tissue cells that produce melanin pigment.

Macrophages

Cells that engulf pathogens, debris, and dead cells through phagocytosis.

Mast cells

Cells that release chemicals such as histamine and heparin during inflammation.

Lymphocytes

Immune cells that monitor tissues and fight infection.

Collagen fibers

Strong and flexible connective-tissue fibers that resist pulling forces.

Elastic fibers

Connective-tissue fibers that allow tissues to stretch and recoil.

Reticular fibers

Connective-tissue fibers that form delicate supporting networks.

Ground substance

The noncellular material containing water, proteins, and carbohydrates that fills spaces between cells and fibers in connective tissue.

Mesenchyme

Embryonic connective tissue containing stem cells that can divide and differentiate into various connective-tissue cells.

Brown fat

Adipose tissue containing many mitochondria and a rich blood supply that produces heat through nonshivering thermogenesis in infants.

Stroma

A soft internal supporting framework formed by reticular tissue in organs like lymph nodes, spleen, and bone marrow.

Tendons

Dense regular connective tissue structures that attach muscle to bone.

Ligaments

Dense regular connective tissue structures that attach bone to bone.

Aponeuroses

Broad, flat sheets of dense connective tissue that connect muscles to bones or other muscles.

Fasciae

Sheets or bands of dense irregular connective tissue that surround, separate, stabilize, and support muscles and organs.

Plasma

The watery extracellular matrix of blood.

Hyaline cartilage

The most abundant cartilage type, having a smooth, glassy appearance and providing support and cushioning.

Elastic cartilage

Flexible cartilage containing elastic fibers, located in the external ear and epiglottis.

Fibrocartilage

The toughest type of cartilage, specialized to resist compression and tension in places like intervertebral discs, pubic symphysis, and menisci.

Interstitial growth

Cartilage growth that expands from within as chondrocytes divide and secrete new matrix.

Appositional growth

Cartilage growth that occurs on its outer surface as cells in the perichondrium add new tissue.

Mucous membrane

Tissue membrane lining passageways that open to the outside (digestive, respiratory, urinary, reproductive) that functions to protect, lubricate, absorb, and secrete.

Serous membrane

Tissue membrane lining closed internal body cavities that produces fluid to reduce friction between organs.

Cutaneous membrane

The skin; covers the outer body surface to protect, prevent water loss, and help regulate temperature.

Synovial membrane

Connective-tissue membrane lining joint capsules, bursae, and tendon sheaths that produces synovial fluid for lubrication and nourishment.

Skeletal muscle

Voluntary, striated muscle tissue composed of long, cylindrical fibers with multiple peripheral nuclei.

Cardiac muscle

Involuntary, striated muscle tissue with short branching cells, central nuclei, and intercalated discs, located in the heart wall.

Smooth muscle

Involuntary, nonstriated muscle tissue made of spindle-shaped cells with one central nucleus, found in walls of hollow organs and blood vessels.

Intercalated discs

Specialized mechanical and electrical connections between cardiac muscle cells that coordinate contractions.

Neurons

Specialized nervous tissue cells that detect stimuli and transmit electrical impulses.

Neuroglia

Support cells in nervous tissue that protect, repair, and provide nutrients to neurons.

Regeneration

The replacement of damaged cells with the same type of cells, restoring normal structure and function.

Necrosis

The death of cells or tissues caused by injury, infection, toxins, lack of oxygen, or loss of blood supply.

Pus

A thick fluid consisting of dead white blood cells, tissue debris, pathogens, and fluid formed during inflammation or infection.

Abscess

A localized collection or pocket of pus within a tissue, organ, or confined space.