Tissue structure & Function

General function of Simple Epithelia

1 cell thick, absorbtion, secretion, filtration

2 main types of Epithelium:

1) Protective covering of surfaces or lining cavities *Outside surface * Digestive *Respiratory *Heart/blood vessels * Lining of Body Cavities 2)Glandular Epithelium

3 main parts of connective tissue

1.) Ground Substance- Non- Living 2.) Fibers- Non-living 3.) Cells- Living part

Specialized Junctions: Gap Junctions

Allows communication, Ions pass through Communicating junction between adjacent cells, allow ions simple sugars & molecules to pass from one cell to the other. Location: Heart, smooth muscles where ion passages are required for electrical ac tivity and contrations.

Muscle Tissue: Striated

Bands of striation

Nervous:

Control

Main Tissue Types:

Epithelium, Connective, Muscle, Nervous

Extracelluar Matrix:

Fills space between cells contains fibers White background/ watery substance adhesion proteins, Protein fibers

Exocrine:

Glands with ducts Lined with epithelium Secrete onto body surfaces & into body cavities Examples: Liver Bile

Tissues:

Groups of cells similar in structure and perform a common function

Endocrine:

Have no ducts Produce hormone

Specialized Junctions: Tight Junctions

Hold tight together, proteins of adjacent cells fuse together. Location: epithelial cells of intestines

Cells of connective tissue: Cytes

Maintain Matrix

Muscle Tissue: Smooth Muscle

Structure-tapered at each end, non striated single nucleus Function-Regulates size of organs, fluid through vessels, create goose bumps, peristalis, involuntary Location- Hollow organs- Stomach, intestines, blood vessels

Connective tissue: Blood

Structure: Blood cells surround by matrix Function: Carry food, oxygen, waste products, other materials Location: Blood Vessels

Connective tissue: Dense Regular tissue:

Structure: Closely packed collagen fibers in one direction, fibroblasts present, little ground substance Function: Binds tissue together firmly resists pulling forces Location: Ligaments, tendons, aponeuroses (white sheet over Muscles)

Connective tissue: Cartlidge

Structure: Collagen fibers matrix has high water content, chondrocytes in Lucanae, avascular no nerve fibers 3 types: Hyaline: Nose, ribs to sternum Elastic: Ears Fibrocartidge: intervetebral discs Function: Firm but flexible support withsatands tension, compression Location: Ends of bones, ears, discs

Connective tissue: Adipose Tissue

Structure: Contains Large amounts of lipids, nucleus to side Function:insulates cushions stores energy Location: under skin, heart, kidney, mammory glands

Connective tissue: Bone

Structure: Hard Calcified matrix, osteocytes in Lucanae Cancellous: Spongy Bone Compact: Concentric circles Function: Support, protection, fat storage, blood cell synthesis Location: Bones of skeleton

General function of Stratified Epithelia

Two or more cells thick, major role is protection

Connective Tissue: Binding & support-

bones, tendons, ligaments

Connective tissue: Main Function: Protection-

fat bones aerilar tissue

Connective tissue: Main Function: Insulation & cushioning

fat, aerioloar tissue

Route of Hormones:

gland, extra cellular space, Blood lymphatic , target organ Some are formed from non-Epithelial tissue

Two types of Exocrine: 2. Multicellular

multiple cells, classified by structure and mode of secretion

Secretion:

release of a product

Two types of Exocrine: 1. Unicellular

single cells, Goblet, Mucus Cells Location: epithelual linings of intestines, respritory tracts

Elastic:

stretch & recoil

Collagen:

tough with high tensile stregnth

Connective tissue: Main Function: Transportation

Blood

Cells of connective tissue: Clasts

Break down Matrix

Exocrine Glands Mode of Secretion: Holocrine

Cells accumulate product until they rupture. Cells "die for a cause" Examples: Sebaceous glands, black heads

Muscle Tissue: Voluntary

Consciously controlled

Glandular Epithelia: Gland

Consist of one or more cells that make or secrete a product

Connective Tissue:

Makes up part of every organ in the body. Most abundant & widely distibuted

Epithelium:

Protects, covers

Fibers:

Provide support

Cells of connective tissue: Blasts

Secrete Matrix (make more)

Muscle Tissue: Skeletal

Striated- Voluntary

Muscle Tissue: Cardiac

Striated- inoluntary

Muscle Tissue: Cardiac Muscle

Structure- Cylindrical striated, branching single centrally located nucleus, connected by intercalated disks Function-Pump blood, involuntary control Location- Heart

Muscle Tissue: Skeletal Muscle

Structure-Striated Bands, cells are large, long, cylindrical with many nuclei Function- Movement of body under voluntary control Location- attached to bone

Connective tissue: Areolar Tissue

Structure: Fibroblasts equals fiborous matrix, reticular & elastic fibers, collagen, marophages, mast cells Location: Widespread, under skin between muscles & tissue, universal packing material Function: Binds tissue & organs loosely and delicately, Holds body fluids stores Nutrients

Epithelial Tissue: Stratified Squamous

Structure: Multi Layer, Cuboidal or Columnar Function: Protect against abrasions, infection, prevents loss of water Location: Skin, mouth, throat, esophagus, anus, vagina Shape: Stratified cuboidal columnar

Epithelial Tissue: Stratified Cuboidal

Structure: Multiple layer of cuboidal Shape cells Function: Secretion, absorbtion, protection against infection. Location: Sweat glands ducts, salivary glands, ovarian follicular cells, mammory glands Shape: Stratified, columnar

Nervous tissue:

Structure: Neurons, the actual conducting cells of nervous tissue Cell body Dendrites: Info In Axon: Info Away Function: Generate & conduct Nerve impulses Location: Brain, Spinal cord, Nerves

Connective tissue: Dense Irregular Tissue

Structure: Similar to dense regular except collagen fibers are in a irregular pattern Function: allows for pulling forces in many different directions Location: Dermis of skin, fiborous joints

Epithelial Tissue: Simple Cuboidal

Structure: Single Layer, cube shaped Function: Secretion & Absorbtion Location: Walls of ducts of glands & kidney tubules Shape: Simple, Cuboidal

Epithelial Tissue: Simple Squamous Epithelium

Structure: Single Layer, flattened cells Function: diffusion, filtration protection against friction, secretion, absorbtion. Location: Kidneys Lungs blood vessels serious membrane Shape: Simple, Flattened, Squamous

Epithelial Tissue: Simple Columnar

Structure: Single layer tall/narrow Function: Movement (ciliated) of particles out of bronchials secretion of glands stomach intestines, absorbtion in intestines Shape: Simple, Columnar

Epithelial Tissue: Transitional

Structure: Stratified cells that appear cuboidal when relaxed, Squamous when stretched Function: allows for fluctuations in volume of fluid Location: Bladder, uterous, superior urethra Shape: Stratified, cuboidal, or squamous

Histology:

Study of Tissue

Cytology:

Study of cells

Connective:

Supportive

Exocrine Glands Mode of Secretion: Merocrine

Most abundant, Secretes by exocytosis (release) Examples: Pancreas, sweat glands, salivary glands

Muscle:

Movement

Muscle Tissue: Nonstraited

No bands of striation

Muscle Tissue: Smooth muscle

Nonstriated- involuntary

Specialized Junctions: Desmosomes

Not as tightly held together Anchoring junctions- Prevents seperations of adjoining cells Location: Skin, Heart

Muscle Tissue: Involuntary

Not consciously controlled

Types of Multicelluar Structure:

Simple: unbranched ducts Compound: Branched Ducts Tubular: Secretory cells form tubes alvoler- cells form small "flask like" cells Tubuloalveolar- have both Secretory cells and "flask like" cells

Reticular support:

Soft tissue