Chapter 4 power point Flashcards
how are tissues classified?
Tissue classification is based on structure of cells, composition of noncellular extracellular matrix, and cell function
what is a biopsy and autopsy?
Biopsy: removal of tissues for diagnostic purposes
Autopsy: examination of organs of a dead body to determine cause of death
what are the 3 germ layers?
endoderm, mesoderm, and ectoderm
what is the endoderm?
Inner layer
Forms lining of digestive tract and derivatives
what is the mesoderm?
Middle layers
Forms tissues as such muscle, bone, blood vessels
what is the ectoderm?
Outer layer
Forms skin and nervous tissue
Extracellular
formed by secretions of both epithelium and connective tissue.
Acellular
“glue”
Attachment to C.T.
Guides cell migration during tissue repair
Acts as a filter in the nephron of the kidney
what are the functions of epithelial tissue?
Protecting underlying structures; e.g., epithelium lining the mouth
Acting as barriers; e.g., skin
Permitting the passage of substances; e.g., nephrons in kidney
Secreting substances; e.g., pancreas
Absorbing substances; e.g., lining of small intestine
simple epithelial
one layer of cells. Each extends from basement membrane to the free surface
stratified epithelial
more than one layer. Shape of cells of the apical layer used to name the tissue. Includes transitional epithelium where the apical cell layers change shape depending upon distention of the organ which the tissue lines
Pseudostratified epithelial
tissue appears to be stratified, but all cells contact basement membrane so it is in fact simple
what are the shapes of epithelial cells?
Shape of cells
Squamous- flat, scale-like
Cuboidal- about equal in height and width
Columnar- taller than wide
what are the functions of simple epitheial
Simple: allows diffusion of gases, filtration of blood, secretion, absorption
what are the functions of stratified squamous epithelial
Stratified: protection, particularly against abrasion in skin, mouth, throat, esophagus, anus, and vagina
what are the functions of squamous epitihelial
Squamous: allows diffusion or acts as filter
what are the functions of cuboidal and columnar
Cuboidal and Columnar: secretion or absorption. May include goblet cells that produce and secrete mucus
what can be on the surface of epithelial cells?
what are the functions?
Microvilli: increase surface area for absorption or secretion
Stereocilia: elongated microvilli for sensation and absorption
Cilia: move materials across the surface
where are cell connections found?
Found on lateral and basal surfaces of cells
what are the functions of cell connections?
Form permeability layer
Bind cells together
Provide mechanism for intercellular communication
what is a Hemidesmosomes? what does it do?
half of a desmosome; attach epithelial cells to basement membrane.
what is the difference between exocrine and endocrine, concerning ducts.
endcrine does not have ducts, exocrine has ducts
what are the glands structures?
Unicellular: goblet cells
Multicellular: branched, alveolar; pancreas/alveolar sacs of the lungs
what are the functions of CT
Enclose organs as a capsule and separate organs into layers
Connect tissues to one another. Tendons and ligaments.
Support and movement. Bones.
Storage. Fat.
Cushion and insulate. Fat.
Transport. Blood.
Protect. Cells of the immune system.
What are the cells of CT?
Specialized cells produce the extracellular matrix
Blasts
Blasts: create the matrix, example osteoblast
Cytes
Cytes: maintain the matrix, example chondrocyte
Clasts
Clasts: break the matrix down for remodeling, example osteoclasts
Adipose CT
fat cells (adipocytes). Common in some tissues (dermis of skin); rare in some (cartilage)
mast cells ct
Common beneath membranes; along small blood vessels. Can release heparin, histamine, and proteolytic enzymes in response to injury.
White blood cells
(leukocytes). Respond to injury or infection
Macrophages
Phagocytize or provide protection
Fixed: stay in position in connective tissue
Wandering: move by amoeboid movement through the connective tissue
platelets
Fragments of hematopoietic cells involved in clotting.
Undifferentiated mesenchyme
(stem cells). Have potential to differentiate into adult cell types
collagen
Collagen. Most common protein in body; strong, flexible, inelastic
reticular
Reticular. Fill spaces between tissues and organs. Fine collagenous, form branching networks
elastic
Elastic. Returns to its original shape after distension or compression. Contains molecules of protein elastin that resemble coiled springs; molecules are cross-linked
what are 3 protein fibers?
collagen, elastic, and reticular
loose ct
Loose (areolar). Collagenous fibers are loosely arranged, connects skin to muscle
dense ct
Dense. Fibers form thick bundles that nearly fill all extracellular space, tendons connect muscle to bone
Tendons
Tendons: Connect muscles to bones;fibers are not necessarily parallel
ligaments
Ligaments: Connect bones to bones. Collagen often less compact, usually flattened, form sheets or bands
free surfaces of epithelial cells can be
smooth or folded
what does a smooth surface do?
reduce firction
what do the folds do on the surface of epithelium?
Folds: in transitional epithelium where organ must be able to change shape.
Hyaluronic acid:
polysaccharide. Good lubricant. Vitreous humor of eye, joints
Proteoglycans
protein and polysaccharide. Protein part attaches to hyaluronic acid. Trap large amounts of water..
Adhesive molecules
hold proteoglycan aggregates together.
Chondronectin
in cartilage, osteonectin in bone, fibronectin in fibrous connective tissue.
mucus
Mucus: found only in the umbilical cord. Wharton’s jelly.
