Chapter 4 Flashcards
Tissue classification based on structure of cells, composition of noncellular, — and cell function.
extracellular matrix
microscopic study of tissues.
Histology
removal of tissues for diagnostic purposes
Biopsy
examination of organs of a dead body to determine cause of death.
Autopsy
form early in embryonic development and give rise to all tissues of the body.
Embryonic germ layers
• Inner layer
• Forms lining of digestive tract and derivatives
Endoderm
• Middle layer
• Forms tissues as such muscle, bone, blood vessels
Mesoderm
• Outer layer
• Forms skin and neuroectoderm (which forms nervous system; neural crest cells give rise to peripheral nerves, skin pigment cells, medulla of the adrenal gland, and face tissues.)
Ectoderm
• Mostly composed of cells; very little extracellular matrix
• Covers body surfaces and forms glands.
epithelial tissue
connects the basal layer to underlying tissue
Basement membrane
materials must move by diffusion from underlying connective tissue
Avascular
Consists of two layers - basal lamina and reticular lamina
Basement Membrane
Consists of two layers - basal lamina and reticular lamina
Basement Membrane
consists of lamina lucida and lamina densa
Basal lamina
one layer of cells. Each extends from basement membrane to the free surface.
Simple
more than one layer. Shape of cells of the apical layer used to name the tissue.
Stratified
tissue appears to be stratified, but all cells contact basement membrane, so it is in fact simple.
Pseudostratified columnar
special type of stratified epithelium where the cell shape changes from cuboidal/columnar to squamous-like when stretched.
Transitional
flat, scalelike.
Squamous
about equal in height and width.
Cuboidal
taller than wide.
Columnar
Free surfaces of epithelium.
Free Surface Modifications
reduce friction; called endothelium
Smooth
in transitional epithelium where organ must be able to change shape; urinary bladder.
Folds
increase surface area for absorption or secretion.
Microvilli
are modified as sensory receptors; stereocilia of the inner ear (not cilia).
Specialized microvilli
move mucus across the surface of cells.
Cilia
Cell Connections
Found on lateral and basal surfaces of cells.
disk-shaped regions of cell membrane; often found in areas that are subjected to stress.
• Consists of an especially adhesive material between the cells and intermediate protein filaments that extend into cytoplasm of cells.
• Stratified squamous epithelium of the skin.
Desmosomes
half of a desmosome; attach epithelial cells to basement membrane preventing movement of the tissue.
Hemidesmosomes
hold cells together, form permeability barrier.
Tight Junctions
found just below tight junctions that help anchor epithelial cells to each other to prevent passage of materials between cells; provides additional strength to the tight junctions.
Adhesion belts
protein channels aid intercellular communication.
• Allows ions and small molecules to pass through.
• Function in epithelium is unclear.
Gap Junctions
protein channels aid intercellular communication.
• Allows ions and small molecules to pass through.
• Function in epithelium is unclear.
Gap Junctions
Specialized secretory organs of epithelium with supporting network of С.Т.
Glands
no open contact with exterior; no ducts; have an extensive network of blood vessels; produce hormones.
Endocrine
open contact maintained with exterior by way ducts that open onto the free surface of the epithelium.
Exocrine
• Multicellular glands with a single, nonbranched duct.
• Secretory portion can be tubular or acinar (sac-like)
• Includes simple tubular, simple branched tubular, simple acinar, and simple branched acinar
Simple glands
• Multicellular glands with ducts with many branches.
• Secretory portion may be tubular, acinar or both.
• Includes compound tubular, compound acinar, and compound tubuloacinar.
Compound glands
exocytosis (most common type).
Merocrine
pinched off fragments of gland cells; mammary glands and ceruminous glands.
Apocrine
shedding of entire cells; sebaceous glands.
Holocrine
Abundant; found in every organ.
Connective Tissue
Specialized cells produce the extracellular matrix. Descriptive word stems.
Cells of Connective Tissue
create the matrix.
Blasts
maintain the matrix.
Cytes
break the matrix down for remodeling.
Clasts
form the structural framework of the body include bone cells, cartilage cells, and fibrous tissue cells.
C.T. cells
form bone, osteocytes maintain it, and osteoclasts break it down.
Osteoblasts
_____ form cartilage and _____ maintain it
Chondroblasts and chondrocytes
____ form fibrous connective tissue and ____ maintain it.
Fibroblasts and fibrocytes
Common in some tissues (dermis of skin); rare in some (cartilage).
Adipose or fat cells (adipocytes)
Common beneath membranes and along small blood vessels. Important role in inflammation; can release heparin, histamine, and proteolytic enzymes in response to injury.
Mast cells
Respond to injury or infection.
White blood cells (leukocytes)
Phagocytize to provide protection against foreign and injured cells.
Macrophages
stay in position in connective tissue.
Fixed
move by amoeboid movement through the connective tissue.
Wandering
Fragments of hematopoietic cells involved in clotting
Platelets
Have potential to differentiate into adult cell types
Undifferentiated mesenchyme (stem cells)
Three major components to the extracellular matrix: protein fibers, ground substance, fluid.
Extracellular Matrix
Most common protein in body; strong, flexible, inelastic.
Collagen
Fill spaces between tissues and organs. Fine collagenous, form branching networks.
Reticular
Returns to its original shape after distension or compression. Contains molecules of protein elastin that resemble coiled springs; molecules are cross-linked.
Elastic
Most common molecules are called the?
ground substance
polysaccharide. Good lubricant. Vitreous humor of eye.
Hyaluronic acid
protein and long polysaccharides called glycosaminoglycans. Protein part attaches to hyaluronic acid. Trap large amounts of water.
Proteoglycans
hold proteoglycan aggregates together. Chondronectin in cartilage, osteonectin in bone, fibronectin in fibrous connective tissue.
Adhesive molecules
2 Embryonic CT:
• Mesenchyme.
• Mucous CT.
2 Embryonic CT:
• Mesenchyme.
• Mucous CT.
fewer fibers, more ground substance; areolar, adipose, reticular
Loose
fewer fibers, more ground substance; areolar, adipose, reticular
Loose
more fibers, less ground substance; dense regular and irregular collagenous, dense regular and irregular elastic
Dense
semisolid matrix; hyaline, fibrocartilage, elastic
Cartilage
solid matrix; spongy and compact
Bone
Dense irregular connective tissue that surrounds cartilage. Fibroblasts of perichondrium can differentiate into chondroblasts.
Perichondrium
Types of cartilage
• Hyaline.
• Fibrocartilage.
• Elastic.
gives strength and rigidity; allows bone to support and protect other tissues and organs.
Matrix
collagen fibers.
Organic
hydroxyapatite (calcium and phosphate).
Inorganic
located in lacunae with a rich blood supply.
Osteocytes
• Contracts or shortens with force.
• Moves body and pumps blood.
Muscle Tissue
most attached to skeleton, but some attached to other types of connective tissue; striated and voluntary.
Skeletal
muscle of the heart; striated and involuntary.
Cardiac
muscle associated with tubular structures and with the skin; nonstriated and involuntary.
Smooth
have the ability to produce electrical signals called action potentials.
Neurons (nerve cells)
contains nucleus.
Cell body
cell process; conducts impulses away from cell body; usually only one per neuron.
Axon
cell processes; receive impulses from other neurons; can be many per neuron.
Dendrites
are support cells of the brain, spinal cord and nerves. Nourish, protect, and insulate neurons.
Glia
Thin sheet of tissue that covers a structure or lines a cavity. Consist of superficial epithelial tissue and underlying connective tissue. Cutaneous mucous, serous, and synovial.
Tissue Membranes
• Line cavities that open to the outside of body.
• Secrete mucus.
• Contains epithelium with goblet cells, basement membrane, lamina propria (sometimes with smooth muscle).
• Found in respiratory, digestive, urinary and reproductive systems.
Mucous
Simple squamous epithelium called mesothelium, basement membrane, thin layer of loose C.T.
• Line cavities not open to exterior.
• Pericardial, pleural, peritoneal.
Serous
• Line freely movable joints.
• Produce fluid rich in hyaluronic acid.
Synovial
Body responds to tissue damage or infection with an?
inflammatory response
in the skin causes damage and introduces bacteria.
splinter
Chemical mediators of inflammation (histamine, kinins, prostaglandins, leukotrienes, and others) are released or activated in injured tissues and adjacent blood vessels. Some blood vessels rupture, causing bleeding.
Chemical mediators cause capillaries to ___ and the skin to become red and warm.
dilate
new cells of same type are produced; function is restored.
Regeneration
new type of tissue develops, resulting in scar and loss of some function.
Replacement
capable of mitosis through life; skin, mucous membranes, hematopoietic tissue, lymphatic tissue.
Labile
no mitosis after growth ends, but can divide after injury; liver, pancreas, endocrine cells.
Stable
if killed, replaced by a different type of cell; limited regenerative ability; nervous, skeletal and cardiac muscle.
Permanent
edges of wound are close together. Wound fills with blood.
Primary union
fibrin threads start to contract; pull edges together.
Clot forms
Inflammatory response; pus forms as white cells die.
Scab
Replaces clot, delicate C.T. composed of fibroblasts, collagen fibers, capillaries.
Granulation tissue
Formed from granulation tissue. Tissue turns from red to white as capillaries are forced out.
Scar
occurs leading to greater scarring.
Wound contraction
Blood vessel permeability increases, resulting in?
edema
isolates and walls off microorganisms and other foreign matter.
Fibrin
Phagocytic white cells called ___ then move into the tissue to help fight the infection?
neutrophils
from surrounding CT migrate into the clot and produce collagen and other extracellular matrix components.
Fibroblasts
cancers of epithelial tissue; include nearly all lung, breast, colon, prostate, and skin cancers.
Carcinomas
derived from glandular epithelium.
Adenocarcinomas
relatively rare cancers of mesodermal tissue (connective and muscular)
Sarcomas
