Exam2

Tissue

A group of similar cells and their products that work together to perform a specific function.

Histology

The study of tissues

Primary tissue types

Epithelial

Connective

Muscle

Nervous (Neural)

Epithelial

Covers body surfaces, lines cavities, and forms glands.

Covering Epithelium

Covers external body surfaces.

Lining Epithelium

Lines body cavities, hollow organs, ducts, and passageways.

Glandular Epithelium

Specialized epithelial tissue that produces secretions

Endocrine Glands

Ductless glands that secrete hormones directly into the Bloodstream

Exocrine Glands

Glands that secrete through ducts onto body surfaces or into body cavities.

Polarity

Presence of distinct apical and basal surfaces in epithelial cells.

Apical Surface

Free surface facing the body exterior or lumen.

Basal Surface

Attached surface connected to the basement membrane.

Basement membrane

Anchors epithelial tissue to underlying connective tissue.

Basal Lamina

Portion of the basement membrane produced by epithelial cells.

Reticular Lamina

Portion of the basement membrane produced by connective tissue.

Avascular

Lacking blood vessels

Innervated

Supplied with nerves

Microvilli

Finger-like projections that increase surface area for absorption.

Cilia

Hair-like projections that move substances across the epithelial surface.

Dense Regular Connective Tissue

Parallel collagen fibers found in tendons and ligaments.

Dense Irregular Connective Tissue - Irregular collagen fibers that resist forces from many directions.

Irregular collagen fibers that resist forces from many directions.

Cartilage

Firm connective tissue containing chondrocytes.

Chondroblast

Cell that produces cartilage matrix.

Chondrocyte

Mature cartilage cell within a lacuna.

Lacuna

Small cavity housing cartilage or bone cells.

Hyaline Cartilage

Most common cartilage; supports and reduces friction.

Elastic Cartilage

Flexible cartilage found in the ear and epiglottis.

Fibrocartilage

Strong cartilage that resists compression.

Bone (Osseous Tissue)

Mineralized connective tissue providing support and protection.

Osteon

Structural unit of compact bone.

Osteocyte

Mature bone cell.

Central Canal

Contains blood vessels and nerves in an osteon.

Canaliculi

Tiny channels connecting osteocytes.

Mucous Membrane (Mucosa)

Lines body passages that open to the exterior.

Serous Membrane (Serosa)

Lines closed body cavities.

Cutaneous Membrane

The skin.

Synovial Membrane

Connective tissue membrane lining freely movable joints.

Synovial Fluid

Lubricates joints and nourishes cartilage.

Skeletal Muscle

Voluntary muscle attached to bones.

Cardiac Muscle

Muscle found only in the heart.

Smooth Muscle

Involuntary muscle found in hollow organs.

Neural Tissue

Tissue specialized for communication by electrical impulses.

Inflammation

Immediate response to tissue injury characterized by redness, heat, swelling, and pain.

Tight Junctions

Seal neighboring cells and prevent leakage.

Adherens Junctions

Provide mechanical attachment between adjacent cells.

Desmosomes

Strong anchoring junctions that resist mechanical stress.

Gap Junctions

Allow communication between adjacent cells.

Simple Epithelium

One layer of cells.

Stratified Epithelium

Two or more layers of cells.

Squamous Cells

Flat cells.

Cuboidal Cells

Cube-shaped cells.

Columnar Cells

Tall, rectangular cells.

Pseudostratified Columnar Epithelium - Single layer that appears multilayered because nuclei are at different levels.

Single layer that appears multilayered because nuclei are at different levels.

Transitional Epithelium

Stretchable epithelium found in the urinary tract.

Connective Tissue

Tissue that supports, protects, binds, stores energy, and transports materials.

Ground Substance

Gel-like material between connective tissue cells.

Matrix

Ground substance plus fibers.

Fibroblast

Cell that produces connective tissue fibers and ground substance.

Macrophage

Phagocytic cell that removes pathogens and debris.

Mast Cell

Releases histamine and heparin.

Adipocyte

Fat storage cell.

Collagen Fibers

Strong fibers that resist stretching

Reticular Fibers

Form supportive frameworks (stroma)

Elastic Fibers

Stretch and recoil.

Areolar Connective Tissue

Loose connective tissue beneath epithelia.

Adipose Tissue

Fat tissue used for energy storage, insulation, and protection.

Histamine

Causes vasodilation during inflammation.

Heparin

Natural anticoagulant released by mast cells.

Necrosis

Death of living tissue.

Regeneration

Replacement of damaged tissue with new functional tissue.