Tissues

• A group of cells with similar structure and function.

• Types:– Epithelial– Connective– Muscle– Nervous

Epithelial Connective Muscle Nervous Credits

Epithelial Tissues• Avascular but inverted• Regenerative• Special contacts• Composed entirely of

cells• Supported by connective

tissue• Three types

– Squamos– Cuboidal– Columnar

Home Squamos Columnar Cuboidal Transitional

Simple Squamos

• Single layer of flattened cells with disc shaped nuclei; sparse cytoplasm

• Functions– Diffusion and filtration– Provides a slick lining in

lymphatic and cardiovascular systems

Home Epithelial Stratified Squamos

Stratified Squamos

• Composed of several layers of cells

• Protects underlying areas subjected to abrasion

• Located in the epidermis, linings of the esophagus and mouth

Home Epithelial Simple Squamos

Simple Cuboidal

• Single layer of cube like cells with large spherical nuclei

• Secrets and absorbs in kidney tubules, ducts of glands and ovary surface

Home Epithelial Stratified Cuboidal

Stratified Cuboidal

• Rare in body• Typically two cell layers

thick• Found in sweat and

mammary glands

Home Epithelial Simple Cuboidal

Simple Columnar

• Single layer of tall cells with oval nuclei; many contain cilia

• Absorbs and secretes• Non-ciliated type line

digestive tract and gall bladder

• Ciliated type lines small bronchi, uterine tubes, and some regions of the uterus

Home Epithelial Stratified Columnar Psuedostratified Columnar

Stratified Columnar

• Limited in body• Found in pharynx, male

urethra ad lining of glandular ducts

• Also at transitional areas between two other types of epithelium

Home Epithelial Simple Columnar Pseudostratified Columnar

Pseudostratified Columnar• Single layer of cells with

different heights• Nuclei are seen at

different layers• Secretes and propels

mucous• Present in male sperm

carrying ducts (non-ciliated) ,and in the trachea (ciliated)

Home Epithelial Simple Columnar Stratified Columnar

Transitional

• Several cell layers thick• Stretches to permit

distension of the bladder

• Lines bladder, uterus and part of the urethra

Home Epithelial Columnar Squamos Cuboidal

Connective Tissues

• Ten Types– Proper: dense regular– Proper: dense irregular– Proper: loose reticular– Proper: loose arealar– Proper: loose adipose– Hyaline cartilage– Elastic cartilage– Fibrocartilage– Osseous (bone)– Blood

Home Proper Cartilage Bone Blood

Proper: Dense Regular

• Parallel collagen fibers with a few elastic fibers

• Major cell type is fibroblasts

• Attaches muscles to bone and other muscles to and bone to bone

• Found in tendons and ligaments

Home Connective Tissue Dense Irregular Loose Adipose Loose Reticular Loose Arealar

Proper: Dense Irregular

• Irregularly arranges collagen fibers with some elastic fibers

• Fibroblasts is the major cell type

• Withstands tension in many directions

• Found in dermis, submucosa of digestive tract and fibrous organ capsules

Home Connective Tissue Dense Regular Loose Adipose Loose Reticular Loose Arealar

Loose: Adipose

• Very sparse matrix• Closely packed fat cells,

nuclei pushed to one side by large fat droplets

• Insulates heat and protects organs

• Found under skin, around kidneys, eyeballs and in breasts

Home Connective Tissue Dense Irregular Dense Regular

Loose Reticular Loose Arealar

Loose: Areolar

• Gel like matrix with all 3 fiber types; fibroblasts, macrophages, and some white blood cells

• Cushions organs and holds tissue fluid

• Widely distributed under the epithelial of body

Home Connective Tissue Dense Irregular Dense Regular Loose Adipose Loose Reticular

Loose: Reticular

• Network of reticular fiber in a loose ground substance.

• Forms a soft internal skeleton that supports other cell types.

• Found in lymph nodes, bone marrow and spleen

Home Connective Tissue Dense Irregular Dense Regular Loose Adipose Loose Arealar

Cartilage: Hyaline

• Amphorus, firm matrix with imperceptible network of collagen fibers

• Has lacunae• Supports, reinforce,

cushions and resists compression

• Found in embryonic skeleton

Home Connective Tissue Elastic Cartilage Fibrocartilage

Cartilage: Elastic

• Similar to hyaline but with more elastic fibers

• Maintains shape and structure while allowing flexibility

• Supports external ear

Home Connective Tissue Hyaline Cartilage Fibrocartilage

Cartilage: Fibrocartilage

• Matrix is less firm then hyaline cartilage with thick collagen fibers

• Provides tensile strength and absorbs compression shock.

Home Connective Tissue Hyaline Cartilage Elastic Cartilage

Bone

• Hard, calcified matrix with collagen fibers

• Supports protects and provides levers for muscular action

• Stores calcium, minerals and fats

• Well vascularized• Marrow inside bone is the

site of hematopoiesis

Home Connective Tissue Proper CartilageBlood

Blood

• Red and white cells found in a fluid matrix (plasma)

• Functions in the transport of respiratory gasses, nutrients and wastes

• Contained within blood cells

Home Connective Tissue Proper CartilageBone

Muscle Tissue

• Highly cellular and well vascularized

• Possess myofilaments• Three types

– Skeletal– Cardiac– Smooth

Home Skeletal Cardiac Smooth

Skeletal

• Long cylindrical, multinucleate cells with obvious striations.

• Controls voluntary movement

• Found in skeletal muscles that attach bones or skin.

Home Muscular Tissue Cardiac Smooth

Cardiac

• Branching, striated, uninucleate cells interlocking at intercalated discs

• Propels blood into circulation

• Found in the walls of the heart

Home Muscular Tissue Smooth Skeletal

Smooth

• Sheets of spindle-shaped cells with central nuclei

• No striations• Propels substances

along internal passageways

• Found in the walls of hollow organs

Home Muscular Tissue Cardiac Skeletal

Nervous Tissue

• Branched neurons with long cellular processes

• Transmits electrical signals from sensory receptors to effectors

• Found in brain, spinal cord and peripheral nerves

Home