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