Histology Vocab Flashcards
histology
study of tissues
epithelial tissue
- lines all body surfaces and cavities
- secretes sweat, saliva, etc.
connective tissue
connects all other tissues to one another
muscle tissue
capable of generating for while contracting (your muscles bro)
nervous tissue
capable of generating, sending, and receiving messages
extracellular matrix (ECM)
substances in liquid, thick gel, or solid form that surround cells of tissue
ground substance
the most of the ECM
extracellular fluid (ECF)
- aka interstitial fluid
- the fluid that surrounds cells
Glycosaminoglycans (GAGS)
- traps water in the ECM
- helps ECM to resist compression
Proteoglycans
binds themselves to GAGS (resembles bottle brush)
cell-adhesion molecules (CAMS)
holds everything in place within the ECM
collagen fibers
- make up to 20-25% of ALL proteins in the body
- resistant to pulling and stretching
elastic fibers
- composed of elastin surrounded by
glycoproteins - can return to normal shape after being
stretched
reticular fibers
forms web-like structures in organs to trap foreign cells
tight junctions
holds cells together closely. (is usually water tight.)
desmosomes
- acts like velcro
- strong hold
- allows substances to travel from cell to cell
gap junctions
allows substances to flow freely through the protein channels
avascular
- lack blood vessels
- must obtain
oxygen and nutrients by diffusion from deeper tissues
basement membrane
a thin membrane separating an epithelium from underlying tissue
basal lamina
ECM synthesized by epithelial cells; consists of collagen fibers and ground substance
(THE TOP LAYER) GLUE
reticular lamina
synthesized by underlying connective tissue;
consists of reticular fibers and ground substance
(THE BOTTOM LAYER) GLUE
simple squamous epithelium
- thin layer of skin (one layer)
- flat cells
simple cuboidal epithelium
single layer of cube shaped cells
simple columnar epithelium
single layer of rectangular cells
pseudostratified epithelium
appears layered because cells and tangled, but is really simple columnar
keratinized stratified squamous epi.
the cells on the surface are dead and flaking off
non-keratinized stratified squamous epi.
cells on the surface are still alive
stratified cuboidal epithelium
two cell layers of cube shaped cells
stratified columnar epithelium
top layer is columnar and layer under is cuboidal
transitional epithelium
arched on outside layer, usually cuboidal
paracellular
the transfer of substances across the epithelium by going through the intercellular space
transcellular
the transportation of products by a cell through a cell
gland
- found in the epithelium
- secretes products from designated cells
endocrine gland
secrets products, usually hormones directly into the blood
exocrine gland
releases products onto the surface of the body
unicellular gland/goblet cell
- most common exocrine gland
- secretes mucus into resp. and digest. systems
merocrine secretion
- most common method
- stores and secretes hormones and etc.
holocrine secretion
- accumulate product in cytosol
- only releases product when the cells dies
- pinches off
connective tissue proper
- generally used connective tissue
- connects tissues and organs
specialized connective tissue
has cartilage, bone tissue, and blood
fibroblasts
most common resident cell
adipocytes
- aka fat cells
- in different connective tissues
mast cells
- largest resident cell
- is a immune system cell, releases histamine to cause inflammation (which activates the immune system)
phagocytes
- immune system cells
- ingests foreign substances
areolar tissue
- aka loose connective tissue
- is beneath epithelium of skin
dense irregular tissue
- disorganized collagen bundles
- has all 3 planes of movement
dense regular tissue
organized with parallel collagen bundles
- has one plane of movement
dense elastic connective tissue
parallel squiggly fibers with scattered collagen
reticular tissue
- mostly reticular fibers made by fibroblasts
- forms web like nets that trap foreign substances
adipose tissue
- aka fat tissue
- made of fat storing adipocytes and surrounded by fibroblasts and ECM
cartilage
in joints between bones, ears, nose, and segments of respiratory tract
chondroblasts
- immature cells
- divide by mitosis and make most of ECM
chondrocytes
when a chondroblast surrounds itself with EM in the lacunae and matures
osseous tissue
- aka bone tissue
- supports and protects body
osteocytes
osteoblasts that have surrounded themselves with ECM in lacunae and have matured
plasma
liquid ECM
erythrocyte
red blood cells
leukocyte
white blood cell
platelet
blood clotting cell
excitable tissue
responds to electrical or chemical stimulation
(a muscle)
myocyte
a muscle cell
striated
- myofilaments arranged in alternating light and dark regions; appear
striped - skeletal and cardiac muscle
voluntary
conscious
involuntary
unconscious control
intercalated disks
dark line separating individual cardiac muscle cells
neuron
- capable of sending and recieving messages
neuroglia (glial cells)
- support neuron activities
- able to divide by mitosis unlike neurons
membrane
thin sheets of one or more tissues
serous membrane
-is a true membrane
- consists of mesothelium
- line
pericardial, peritoneal, and pleural body
cavities
mesothelium
a thin layer of simple squamous epithelium
synovial membrane
- a true membrane
- lines cavities surrounding joints (shoulders+knees)
synoviocytes
modified fibroblasts that secrete synovial fluid
synovial fluid
a watery, slippery fluid that lubricates joints
mucous membrane
in any part of the body that stays wet (mouth, throat, vagina, nose, digestive tract)
cutaneous membrane
the skin
epidermis
-the outer layer of the skin
-keratinized stratified
squamous epithelium
dermis
- the middle layer of the skin, just under the epidermis
