1. epithelial: covering 2. connective: support 3. nervous: control 4. muscular: movement Most organs have several types of tissues.  Arrangement of tissues determines organ’s structure and function.

 fit close together  forms continuous sheets  bound together by desmosomes and tight junctions  one apical surface (unattached)  exposed to body’s exterior  some slick, some smooth  some with cilia, microvilli

 lowest surface – basement membrane  structure-less  secreted by cells  support  avascular

 protect underlying structures  act a barrier  allow passage of substances  secretion  absorption

2 names 1- # of relative layers simple = one stratified = > 1 2 – shape squamous cuboidal columnar

structure:  single layer on basement layer  flattened cells  disc-shaped nucleus  fit close together function:  diffusion  filtration location:  air sacs of lungs  walls of capillaries  lining of ventral body cavity and covering of cavity organs  kidneys

structure:  single layer on basement layer  cube-like cells  spherical shaped nucleus  Some have cilia or microvilli. function:  active transport  facilitated diffusion  secretion  absorption location:  glands and their ducts  kidney tubules  surface of ovaries

structure:  single layer on basement layer  tall cells; close together  oval nucleus  Some have cilia.  Some have goblet cells. ▪ produce mucus function:  secretion of mucus  absorption  ciliated: propel mucus, move eggs location:  non-ciliated: digestive tract  ciliated: bronchi, uterus

structure:  single layer of mixed height cells attached to basement layer  appears stratified but is not  some goblet cells  some cilia  nuclei at different levels function:  secretion of mucus  ciliated: propulsion of mucus location:  non-ciliated: large glands and their ducts, male urethra  ciliated: trachea, upper respiratory tract

structure:  several layers  Free edge is squamous.  cuboidal/columnar on bottom ▪ can regenerate ▪ New cells pushed to surface to replace surface cells as needed.  keratinized ▪ composed of dead cells  non-keratinized ▪ living cells with moist surface function:  protects underlying tissue  keratinized ▪ protection from abrasion ▪ barrier ▪ reduces water loss  non-keratinized ▪ protection ▪ barrier ▪ allows rapid movement of water

location:  keratinized ▪ epidermis  non-keratinized ▪ linings of mouth ▪ esophagus ▪ vagina

structure:  > 1 layer of cuboidal  relatively rare function:  absorption  secretion  protection location:  sweat gland ducts  ovarian follicular cells  salivary glands

structure:  > 1 layer ▪ upper layer: columnar ▪ lower layer: cuboidal or irregular  relatively rare function:  absorption  secretion  protection location:  mammary gland ducts  larynx  male urethra

structure:  special type of stratified  base cells ▪ stretched: appear squamous ▪ unstretched: appear cuboidal  Surface cells can vary. function:  allows stretching  protects against urine location:  linings that expand ▪ ureters ▪ bladder ▪ part of urethra

 glands  one or more cells that secrete a particular product onto a surface or into a cavity  composed primarily of epithelium structure:  endocrine ▪ ductless  exocrine ▪ have ducts function:  endocrine ▪ secrete into bloodstream  exocrine ▪ empty secretions onto surface location:  endocrine ▪ thyroid ▪ adrenal ▪ pituitary  exocrine ▪ sweat, oil glands ▪ liver ▪ pancreas

 most abundant and widely distributed tissue type  different in fiber type and number of fibers  good blood supply  except: tendons/ligaments – poor blood supply  cartilage – avascular  living cells surrounded by a matrix  what makes this type of tissue different from all others  living cells and non-living substances  separates cells from one another

1. enclosing and separating  form capsules around liver, kidneys  separate muscles 2. connect tissues to one another  Tendons attach muscle to bone.  Ligaments hold bones together. 3. supporting and moving  bones – support for body  semi-rigid cartilage – support in nose, ears, surfaces of joints 4. storing  high energy molecules and minerals 5. cushioning and insulating  Fat beneath skin cushions bones, insulates to conserve heat. 6. transporting blood 7. protecting  immune system, blood, bones

structure:  soft, pliable  gel-like matrix ▪ mostly collagen, few elastic fibers  cells widely separate  fibroblasts  phagocytes  some white blood cells function:  protects  holds internal organs together  cushions (packing material)  holds tissue fluids location:  throughout body  fills spaces between glands, muscles, nerves  under epithelial cells ▪ supports basement layer

structure:  fat cells  Nucleus pushed to side by fat droplets.  very little matrix  closely packed function:  store energy (f00d fuel)  supports and protects organs  insulates location:  under skin  around kidneys, eyeballs, abdomen, breasts

structure:  reticular fibers  look like fibroblasts function:  forms stroma (soft internal skeleton) for other cell types location:  lymph nodes  bone marrow  spleen

structure:  densely packed collagen fibers  fibroblasts function:  attaches muscle to bone or bone to bone location:  tendons  ligaments  lower layers of skin

structure:  firm matrix ▪ looks blue-white, glassy  collagen fibers  chondroblasts  chondrocytes function:  supports  reinforces  allows growth of long bone  resists compression location:  embryonic skeleton  attachment of ribs to breastbone  joints  nasal cartilages  larynx

structure:  less firm than hyaline  white fibers in thick bundles function:  absorbs compressive shock  rigidity with flexibility location:  discs of knee joints  intervertebral discs  pubic symphysis

structure:  elastin in matrix  yellow function:  able to distend and return to original state location:  external ear  epiglottis

structure:  very hard matrix ▪ contain calcium salts and collagen  osteocytes in lacuna (spaces in matrix) function:  supports  protects  Marrow is site for blood cell formation. location:  bones

structure:  liquid matrix  non-living blood plasma contains blood cells  Fibers are soluble protein molecules. function:  transports nutrients and waste location:  capillaries, veins, arteries

 contract (shorten) – makes movement possible  Elongated cells called muscle fiber.  length is greater diameter  Cells resemble tiny threads.  3 types 1. skeletal 2. cardiac 3. smooth

structure :  long, cylindrical  several nuclei per cell located on edges  obvious striations function :  voluntary movement  facial expressions location :  muscles attached to bones or other connective tissue  occasionally skin

structure :  cylindrical, shorter than skeletal  one nuclei per cell  connected by intercalated discs (junctions) function :  involuntary movement to pump blood location :  walls of heart

structure :  spindle shaped, tapered at each end  central nuclei  no striations function :  involuntary control  movement of food in digestive tract  empties urinary bladder location :  walls of hollow organs except heart  skin  eyes

 cells: neurons  irritability and conductivity  Cytoplasm is long extension.  Supporting cells insulate and support.  brain, nerves, spinal cord

structure :  Neurons are branching cells.  extended cytoplasm  Neuroglia insulate and support. function :  transmit electrical signals  coordinating, controlling body activities location :  brain, spinal cord, nerves