HISTOLOGY Flashcards
histology
its the study of tissues and they are arranged into organs
histology synonym
microscopic anatomy
tissue
is the group of cells similar in structure to perform specific function
there are four types of tissue
epithelial tissues
connective tissues
muscular tissues
nervous tissues
tissue that is specialized to form the covering or lining of all internal and external body surfaces except articular cartilage in synovial joint .
epithelial tissue
ectoderm layer
covering external surface
mesoderm layer
lining inner surface of the heart , all body also and lymphatic vessels .
endoderm layer
lining inner surface e.g. lungs , urinary , bladder , exocrine , glands , respiratory system endoderm .
properties of epithelial tissue
- closely packed cells
- no intercellular spaces
- minimal extracellular matrix
- non/vascular // so need a connective tissue support - called // basal lamina or basement membrane
- continuously renewal
subdivided according to three categories
the shape
diversity
metaplasia
shapes of epithelial tissue
squamous
cuboidal
polygonal
columnar
methods of classification
functions
number of layers
- simple
- stratified
simple epithelium
simple squamous epithelium
simple cuboidal epithelium
simple columnar epithelium
simple squamous epithelium
thin, flat plates , they form the lining of cavities such as the blood vessels endothelium , and body cavities mesothelium and bowman’s capsule , usually for exchange of gases
simple cuboidal epithelium
cuboidal in shape . each cell has spherical nucleus in the centre
- found in the ducts of the glands and in the lining of the kidney tubules for secretion
simple columnar epithelium
simple columnar epithelium non ciliated - found in stomach , intestines and gall bladder - specialized for sensory receptors simple columnar epithelium ciliated - found in fallopian tubes of females - for motility
stratified epithelium
stratified squamous epithelium
stratified cuboidal epithelium
stratified columnar epithelium
stratified squamous epithelium
keratinized stratified squamous epithelium
- containing keratin
- the mammalian skin
- for protection against friction and abrasions
nonkeratinized stratified squamous epithelium
- the lining of wet cavity
-
stratified cuboidal epithelium
they protect areas such as ducts of sweat and salivary gland
stratified columnar epithelium
secretion and protection , rare one , found in the conjunctiva
pseudostratified columnar epithelium
ciliated pseudostratified columnar epithelium
non ciliated pseudostratified columnar epithelium
ciliated pseudostratified columnar epithelium
such as those epithelia lining the respiratory passages
non ciliated pseudostratified columnar epithelium
such as those epithelia lining the large ducts of glands
transitional epithelium
it is stratified tissue but it may appear as simple epithelium depending on their status , such as the urinary bladder
the tissue appears stratified when the bladder is empty
the tissue appears as one layer when the bladder is full ‘ it changes from states to another ‘