Tissues, Connective Tissue Types, Membranes, and Muscle Tissue

Vocabulary practice flashcards covering gland secretion methods, connective tissue classifications, cell types, fibers, membranes, cartilage types, bone features, and muscle tissue characteristics based on lecture notes.

Merocrine Secretion

A secretion method where vesicles containing products fuse with the plasma membrane to release contents without damaging the cell; found in most sweat glands.

Apocrine Secretion

A secretion method where a portion of the cell cytoplasm containing the secretions buds off from the exocrine cell, which then repairs itself.

Holocrine Secretion

A secretion method where superficial gland cells burst and die to release their products, requiring replacement by stem cell mitotic division.

Ground Substance

A clear, colorless, viscous fluid filling the space between cells in connective tissue that helps slow the movement of pathogens.

Matrix

The extracellular structure of connective tissue formed by specialized cells, extracellular protein fibers, and ground substance.

Fibroblasts and Fibrocytes

Cells in connective tissue proper responsible for secreting or maintaining connective tissue fibers.

Adipocytes

Fat cells that store lipids as single droplets within tissue.

Mesenchymal Cells

Undifferentiated stem cells of connective tissue proper capable of differentiating into fibroblasts, fibrocytes, or immune cells.

Melanocytes

Cells responsible for creating and storing melanin pigment, giving color to skin, hair, and eyes.

Collagen Fibers

Thick, strong, straight, and flexible protein fibers that provide strength to tendons and ligaments.

Reticular Fibers

Thin, flexible, crosshatching protein fibers forming a meshwork that resists forces from multiple directions.

Elastic Fibers

Thin, wavy, branching protein fibers composed primarily of elastin that allow significant stretching.

Areolar Tissue

A loose connective tissue containing loosely organized cells and fibers in a viscous ground substance that cushions and supports organs.

White Fat

A type of adipose tissue that stores energy, provides cushioning, and is located subcutaneously or viscerally.

Brown Fat

Vascularized adipose tissue rich in mitochondria found mainly in infants and young children that actively produces heat to warm the body.

Reticular Tissue

A loose connective tissue made of reticular fibers forming a tough yet flexible structural framework for organs such as the liver.

Dense Regular Connective Tissue

Connective tissue packed with parallel collagen fibers, found in tendons, ligaments, and aponeuroses.

Aponeurosis

A broad sheet or bundle of dense regular connective tissue that holds tendons together, such as in the palm or sole.

Dense Irregular Connective Tissue

Connective tissue with an interwoven network of collagen fibers providing multi-directional strength; found in the dermis, periosteum, and joint capsules.

Dense Elastic Connective Tissue

Connective tissue dominated by elastic fibers, located in large blood vessels, respiratory pathways, and spinal ligaments.

Superficial Fascia

A layer of connective tissue close to the skin surface that separates the skin from underlying muscle tissue.

Deep Fascia

Connective tissue sheets that wrap around muscle groups, capsules, and organs to separate them.

Subserous Fascia

A layer of loose areolar connective tissue lying deep to deep fascia that lines internal body cavities.

Blood Plasma

The watery liquid matrix of fluid connective tissue containing blood cells and cell fragments.

Lymph

A fluid connective tissue moving through the open lymphatic system containing lymphocytes, cell debris, and pathogens.

Hyaline Cartilage

The most common cartilage type, featuring densely packed collagen fibers; provides tough yet flexible support in joints, ribs, larynx, and trachea.

Elastic Cartilage

Extremely flexible supportive connective tissue dominated by elastic fibers, found in the outer ear, nose, and epiglottis.

Fibrocartilage

Durable cartilage with interwoven collagen fibers that absorbs shock between intervertebral discs and the pubic symphysis.

Lacunae

Small circular chambers within calcified bone matrix that enclose individual osteocytes.

Canaliculi

Small channels in bone matrix allowing nutrient and waste exchange between blood vessels in the central canal and osteocytes.

Periosteum

A membrane of dense irregular connective tissue surrounding the outer surface of bones, protecting them and assisting growth and repair.

Lamina Propria

The underlying layer of loose areolar tissue that anchors epithelial cells in mucous membranes.

Parietal Layer

The outer portion of a serous membrane that lines the inner surface of a body cavity wall.

Visceral Layer

The inner portion of a serous membrane that directly covers the surfaces of internal organs.

Peritoneum

The serous membrane lining the abdominal cavity and covering abdominal organs.

Pleura

The serous membrane lining the pleural cavities and covering the lungs.

Pericardium

The serous membrane enclosing the heart within the mediastinum.

Cutaneous Membrane

The thick boundary layer forming the skin, consisting of stratified keratinized squamous epithelium anchored to areolar and dense irregular connective tissue.

Synovial Membrane

Connective tissue membrane lining joint cavities that produces fluid to lubricate movement.

Skeletal Muscle Tissue

Voluntary, striated muscle tissue composed of long, multinucleated fibers responsible for body movement.

Cardiac Muscle Tissue

Involuntary, striated, branched muscle tissue with single nuclei found in the heart, possessing limited repair capacity.

Smooth Muscle Tissue

Involuntary, non-striated muscle tissue with single nuclei located in organ walls, capable of continuous division and repair.