A&P - Tissues

Histology

Study of tissues

Cell type, cell function, cell matrix ratio

Types of tissues differ by:

Connective, epithelial, muscle, nervous

Four main types of tissues include:

Epithelial Tissue

Either cover or line - set boundary between body compartments or between body and outside environment

Line all body’s surfaces (external/cavities/tracts (tubing)/blood vessels/ducts) & cells tightly packed (very little matrix)

Features of epithelial tissue include:

Avascular (no blood cells)

Simple epithelium is:

Number of cell layers & cell shape

Classification of epithelial issues include:

Simple Squamous Epithelium

Simple Cuboidal Epithelium

Simple Columnar Epithelium

Allow for rapid diffusion & alveoli of lungs & is very thin

Simple Squamous Epithelium function and location is:

Absorption + secretion & sweat glands + kidney tubules

Simple Cuboidal Epithelium function and location is:

Absorption + secretion & GI tract (stomach, intestines)

Simple Columnar Epithelium function and location is:

Pseudostratified Columnar Epithelium

Keratinized Stratified Squamous Epithelium

Non-Keratinized Stratified Squamous Epithelium

Secrete + move mucous & respiratory tract

Pseudostratified Columnar Epithelium function and location is:

Protection + resists abrasion & epidermis

Keratinized Stratified Squamous Epithelium function and location is:

Protection + resists abrasion & Openings to exterior (Mouth, nose, anal canal, vaginal canal)

Non-Keratinized Stratified Squamous Epithelium function and location is:

Non-keratinized Stratified Squamous Epithelium

Passage of food (Esophagus)

Simple Columnar Epithelium

Secrete acid & digestive enzymes (stomach)

Connective Tissue

Support, protect, bind tissues together

Fewer cells & lots of matrix

Features of connective tissue include:

Fibrous connective tissue (dense or loose), Adipose Cartilage (Hyaline, elastic, or fibrocartilage), Bone, Blood

Types of connective tissues include:

Loose/Areolar Connective Tissue

Collagen, elastic, reticular (highly vascular)

Loose/Areolar Connective Tissue has what three fiber types?

Bind epithelial tissues to deeper tissues, passageways blood vessels/nerves/nutrients/wastes & underneath all epithelia + dermis

Loose/Areolar Connective Tissue function and location is:

Adipose Tissue

Provides energy storage, insulation, cushioning (lots of adipocytes/blood vessels) & hypodermis, breast, surrounding organs

Adipose tissue function and location is:

Chondrocytes (cartilage cells) in lacunae (cavities) & fibers and semi-rigid matrix & avascular

Cartilage features include:

Hyaline Cartilage

Most common/most flexible, lacunae often in pairs, smooth/shiny appearance (collagen)

Features of hyaline cartilage include:

Flexible support & Nose, respiratory tract (trachea/broncil), rib cage (costal cartilage), synovial joints (articular cartilage)

Hyaline cartilage function and location is:

Elastic Cartilage

Elastic fibers, random lacunae

Features of elastic cartilage include:

Elastic Support & external ear + epigotis

Elastic cartilage function and location is:

Fibrocartilage

Strongest/most rigid cartilage, lacunae in rows, parallel collagen fibers

Features of fibrocartilage:

Resist compression/absorb shock & Intervertebral discs, pubic symphysis, menisci of knee

Fibrocartilage function and location is:

Bone Tissue

Most rigid tissue, collagen and calcified matrix, arranged in concentric rings (lamellae)

Features of bone tissue include:

Structural support, protection, calcium storage & bone

Bone tissue function and location is:

Blood Tissue

Liquid matrix (plasma) & cells (RBC, WBC, platelets), NO fibers

Features of blood tissue include:

Transport + immune defense & blood vessels + heart

Blood tissue function and location is:

Nervous Tissue

Excitable Tissue & lots of matrix

Features of nervous tissue include:

Rapid Communication & brain, spinal cord, nerves

Nervous tissue function and location is:

Neurons & Glial cells (support, protect, assist neurons)

Nervous tissue cell types are:

Excitable, cells tightly packed, little matrix

Muscle Tissue features are:

Movement & produce body heat

Muscle tissue functions are:

Skeletal Muscle

Parallel muscle fibers, multinucleate, striated

Skeletal muscle charicteristics include:

Voluntary movement & attached to bones/tongue

Skeletal muscle function and location is:

Cardiac Muscle

Short, branched cells, uninucleate, striated

Cardiac muscle characteristics include:

Pump blood & heart

Cardiac muscle function and location is:

Smooth Muscle

Short, tapered cells, uninucleate, no striations

Smooth muscle characteristics include:

Involuntary movements & viscera + blood vessels (internal organs)

Smooth muscle function and location is:

Glycoprotein layer that anchors every epithelium to the connective tissue beneath it

Basement Membrane is a:

Hold cells together, resist mechanical stress, intercellular communication

Intercellular junctions functions include:

Tight junctions, desmosomes, gap junctions

Types of intercellular junctions include:

Fusion of plasma membrane (zipper) & prevent molecules from passing between cells (GI tract, kidney)

Tight Junctions

Cytoskeleton + proteins & resist mechanical stress/hold cells together (skin, heart)

Desmosomes

Pore of proteins connects cytoplasm of cells “tube” & rapid electrical communication (Cardiac muscle) + nutrient distribution (embryo)

Gap Junctions

Dense Connective Tissue

Densely packed collagen fibers (appear shiny/wavy/smooth) & few blood vessels

Features of dense connective tissue include:

Bind tissues together + resist mechanical stress & Regular: Tendons + ligaments; Irregular: Dermis

Dense connective tissue function and location is: