histology Flashcards
patholgy
study of diseases
cytology
study of microscopic features of normal cells
cytopathology
study of cells with disease
histology
study of microscopic features of normal tissue
histopathology
study of tissue with disease
What are the steps from specimen to report?
1) fixation
2) specimen collection / transportation / receipt
3) tissue selection + description
4) tissue processing
5) tissue embedding
6) microtomy
7) staining + mounting
8) quality assurance
9) reporting
10) specimen disposal
11) block + slide archiving
fixation
process of preserving cells
ischaemia
restriction in blood supply to tissues, causing shortage of oxygen + food, and build up of waste
autolysis
uncontrolled release of intracellular enzymes from lysosomes
putrefaction
action of microorganisms that produces gases
How is prevention of cellular deterioration done?
1) fixing
2) freezing
What factors affect the rate of fixation?
1) temperature
2) size of specimen + penetration of fixative
3) volume
4) pH + buffers
5) osmolarity
6) concentration
7) duration
What are the 2 main types of histopathological specimens?
1) biopsy
2) surgical specimen
histological sample
solid tissue
cytological samples
isolated cells
What methods are used for sample collection?
1) incision
2) resection
3) brush cytology
4) needle core biopsy
5) US guided fine needle aspirate
6) excisional biopsy
What methods are used for sampling of skin?
1) excisional biopsy
2) incisional biopsy
3) shave biopsy
4) punch biopsy
excisional biopsy
complete lesion removed with margin of normal skin down to adipose tissue
incisional biopsy
cross-section wedge of tissue through centre of lesion
shave biopsy
horizontal shave of skin lesion with only superficial portion of dermis
punch biopsy
sampling of cancers / tumors / inflammatory skin conditions
What method of fixation is used for histological examination?
neutral buffered formalin
What method of fixation is used for cytological examination?
alcohol fixatives
What strength of formaldehyde is used for routine fixation?
4%
macroscopic description of the specimen
description that includes gross appearance / measurements / details of blocks taken
Who makes histopathological diagnosis?
pathologist
Who tests patients samples?
biomedical scientist
H&E
haematoxylin + eosin
What colour is cytoplasm + nuclei with H&E?
1) cytoplasm = pink
2) nuclei = purple
How thick is simple epithelium tissue?
one cell thick
What are the types of simple epithelium tissue?
1) simple squamous epithelium
2) simple cuboidal epithelium
3) non-ciliated simple columnar epithelium
4) ciliated simple columnar epithelium
5) pseudostratified columnar epithelium
Where is simple squamous epithelium tissue found?
1) lining of the heart
2) lining of blood vessels
3) lining of lymphatic vessels
4) lining air sacs
of the lungs (alveoli)
5) glomerular (Bowman’s) capsule of the kidney
6) mesothelial
lining of the peritoneum
Where is simple cuboidal epithelium tissue found?
1) covering of the ovary
2) lining kidney tubules
3) smaller ducts of many glands
4) secretory portion of some glands such as the thyroid; 5) lines the ducts
of glands such as the pancreas(interlobular duct)
Where is non-ciliated simple columnar epithelium tissue found?
1) lining GI tract (stomach to anus)
2) lines the ducts of many glands + gall
bladder
Where is ciliated simple columnar epithelium tissue found?
1) lining some bronchioles (small airway tubes) of respiratory tract
2) lining
uterine (fallopian) tubes
3) lining efferent ducts of the testes
4) lining central
canal of spinal cord
5) lining ventricles of brain.
Where is pseudostratified columnar epithelium tissue found?
1) airways of most of the upper respiratory tract
2) larger ducts of many glands
3) epididymis
4) part of male urethra
How thick is stratified epithelium tissue?
many cells thick
What are the types of stratified epithelium tissue?
1) stratified squamous epithelium
2) stratified cuboidal epithelium
3) stratified columnar epithelium
4) transitional epithelium
What reagent s dehydration done with?
ethanol
What reagent is clearing done with?
solvent xylene
What reagent is impregnation done with?
molten paraffin wax
Where is stratified squamous epithelium tissue found?
1) superficial layer of the skin (keratinised variety)
2) wet surfaces such as the mouth/oesophagus/part of the larynx/part
of the pharynx/vagina/covers the tongue (non-keratinised variety
Where is stratified cuboidal epithelium tissue found?
1) lining the ducts of adult sweat glands
2) oesophageal gland
3) part of the male
urethra.
Where is stratified columnar epithelium tissue found?
1) lining part of the urethra
2) lining large excretory ducts of some glands (e.g.
oesophageal glands)
3) covering small areas of anal mucous membrane
4) covering the conjunctiva of the eye.
Where is transitional epithelium tissue found?
1) lining the urinary bladder
2) portions of the ureters + urethra
What are the types of epithelial tissues?
1) simple epithelium
2) stratified epithelium
3) glandular epithelium
What are the types of glandular epithelium tissue?
1) endocrine glands
2) exocrine glands
Give some examples of endocrine glands.
1) pituitary,
2) pineal
3) thyroid
4) parathyroid
5) adrenal
6) pancreas
7) ovaries
8) testes
How are exocrine glands classified?
according to the shape of the secretory part
What are the shapes of exocrine glands?
1) simple tubular e.g. crypt of Lieberkuhn (small intestine)
2) simple branched tubular e.g. fundic gland (stomach)
3) simple coiled tubular e.g. sweat gland (skin)
4) simple acinar (alveolar or saccular) e.g. glands of the penile urethra
5) simple branched acinar e.g. sebaceous gland (oil glands associated with hair follicles of the skin)
6) compound tubular e.g.; bulbourethral gland (the Cowper’s gland which is an accessory sex gland of the penis)
7) compound acinar e.g. mammary gland
8) compound tubuloacinar e.g. acinar glands of the pancreas; Brunner’s glands of the duodenum
What are the types of mature connective tissues?
1) loose connective tissue
2) dense connective tissue
3) cartilage
4) bone
5) liquid connective tissue
What are the types of loose connective tissue?
1) areolar connective tissue
2) adipose tissue
3) reticular connective tissue
What are the types of dense connective tissue?
1) dense regular connective tissue
2) dense irregular connective tissue
3) elastic connective tissue
What are the types of cartilage?
1) hyaline cartilage
2) fibrocartilage
3) elastic cartilage
What are the types of bone tissue?
compact bone
What are the types of liquid connective tissue?
1) blood
2) lymph
What does areolar connective tissue consist of?
fibres + several kinds of cells embedded in a semi-fluid ground substance
What does adipose tissue consist of?
adipocytes
adipocytes
cells specialised to store triglycerides as a large centrally located droplet
triglycerides
fats
What does reticular connective tissue consist of?
a network of interlacing reticular fibres + reticular cells
What does dense regular connective tissue consist of?
collagen fibres regularly arranged in bundles with fibroblasts present in rows between bundles
What does dense irregular connective tissue consist of?
predominantly of collagen fibres randomly arranged + a few fibroblasts
What does elastic connective tissue consist of?
predominantly of freely branching elastic fibres with fibroblasts present in spaces between fibres
What does hyaline cartilage consist of?
a bluish-white, shiny ground substance with thin, fine collagen fibres + many chondrocytes
What is the most abundant type of cartilage?
hyaline cartilage
What does fibrocartilage consist of?
chondrocytes scattered among thick bundles of collagen fibres within the extracellular matrix
What does elastic cartilage consist of?
chondrocytes located in a threadlike network of elastic fibres within the extracellular matrix
What does compact bone tissue consist of?
osteons that contain lamella. lacunae, osteocyte, canaliculi, + a central canal
What does spongy bone tissue consist of?
thin columns with red bone marrow filling spaces between the columns
What does blood consist of?
blood plasma + formed elements, red blood cells, white blood cells, + platelets
erythrocytes
red blood cells
leukocytes
white blood cells
thrombocytes
platelets
What does lymph consist of?
several types of cells in a clear liquid extracellular matrix
germinal centre
site within secondary lymphoid organs (lymph node + spleen)
