Lecture 3 - Tissue Flashcards
protein and carbohydrate material that cells produce on and in which they are supported (nonliving material)
Extracellular matrix
functions of ECM
structural support protection filtration nutrient and GF storage regulates cell movement and cell-cell interaction
ECM composed of (2)
ground substance - gel-like
fibers - withstand tensile forces
three components of ground substance
glycosaminoglycans (GAGs) - resist compression
proteoglycans - resist compression; facilitate normal cellular locomotion
glycoproteins - helps cells adhere to ECM
which are the most abundant ECM fibers?
collagen fibers
what is scurvy
lack of vitamin C causing collagen to not form properly
what is Ehlers-Danlos
abnormal cross-links resulting in hypermobile joints and hyperextensive skin
what is Keloid
excessive accumulation of collagen during wound healing
fibers that provide elasticity to stretch and recoil
elastic fibers
Marfan syndrome
elastic fibers don’t develop properly
structural/framework fibers (think mesh)
reticular fibers
a two-part acellular ECM structure that is between epithelium and adjacent connective tissue
basement membrane
two parts of basement membrane
basal lamina (outer/near epi) - molecular filter and path for cells
lamina reticularis (inner)
two types/divisions of epithelium
covering & lining epithelium - sheets of continuous cells
glandular epithelium - epithelial cells modified for secretion
what does it mean to say epithelial cells have polarity?
they have a specific orientation relative to other cells basal lamina
- apical surface - basolateral surface
apical surface of cell faces ______
basal surface of cell marks _______
lumen
boundary between epithelium and connective tissue
classification of covering & lining epithelium:
by number of layers (3)
simple - single layer
stratified - multiple layers; named after superficial layer
pseudostratified - single layer but nuclei are at different levels
classification of covering & lining epithelium:
by shape of cell (5)
squamous - flat, plate-like
cuboidal - cube-like; similar height and width
columnar - tall; height greater than width
transitional - pillow shaped
pseudostratified - tall but irregular shapes
simple squamous typically found in (3)
pulmonary alveoli
loop of Henle
Blood and lymph vessels
simple cuboidal typically found in (2)
ducts of many glands
urinary tubes
simple columnar found in
digestive tract
stratified squamous found in (3)
mouth
oral pharynx
skin
*can be keratinized (keratin replaces nucleus) or non-keratinized
stratified cuboidal found in
lining ducts of sweat glands
stratified columnar found in (2)
eye
regions of male urethra
pseudostratified columnar found in (3)
male urethra
epididymis
trachea
replacement cells in epithelium turnover come from
reserve or germinative cell population
- use existing basal lamina for guidance
general structure of glands (aka glandular epithelium)
parenchyma
secretory granules
stroma
define parenchyma
secretory units + their ducts
part of gland doing the job of product secretion
define stroma
connective tissue that supports parenchyma
supports the job of product secretion
define endocrine gland
ductless, secretes product into blood or lymph
define exocrine gland
has ducts, secretes product onto surface
modes of exocrine secretion (3) and their definitions
holocrine - product accumulates in cytosol, then cell dies and is discharged
apocrine - product accumulates in apex of cell, then that part of the cell pinches off
merocrine - product is formed in the cell, then discharged by exocytosis
how are glands classified? (3)
mode of secretion
nature of secretion (product)
number of cells
three types of secretion
mucus - mucin making mucus
serous secretion - watery fluid + enzymes
mixed - mucous + serous demilunes
example of unicellular glands
goblet cells (single cell with no duct)
types of duct systems in multicellular glands (2)
simple - straight and unbranched
compound - branched
multicellular glands consist of (2)
duct system and secretory unit
types of secretory unit in multicellular glands (3)
tubular
acinar (like grapes)
tubloacinar
three basic types of tissue (think from fetal development)
ectoderm
mesoderm
endoderm
ectoderm forms
nerve and some epithelia
mesoderm forms
all the connective tissue, muscle, and some epithelia
endoderm forms
some epithelia
four functions of connective tissue
structural support
exchange of nutrients and wastes
protection and host defense
storage of fats and minerals
cells in connective tissue (4)
fibroblasts
mast cells
macrophages
adipocytes
four types of connective tissue proper
dense connective tissue
loose (areolar) connective tissue
reticular tissue
adipose tissue
three types of specialized connective tissue
bone
blood
cartilage
which cell is most abundant in CT?
fibroblast
two types of adipocyte
unilocular (white)
multilocular (brown)
round, heavily granulated cell found within CT in many areas
primary cell initiating inflammation
mast cell
chemical mediators found in granules of mast cells
primary mediators (preformed; stored)
- histamine, heparin
secondary mediators (synthesized
- leukotrienes, thromboxane, prostaglandins, platelet activating factor
where does mesenchymal tissue exist in the adult
pulp of teeth
roles of brown fat (name 2)
non-shivering thermogenesis
plays a role in insulin independent blood glucose regulation
