Block 9

klau253's version from 2017-06-02 11:52


Morphologic changes in cell
Question Answer
Pyknosisirreversible condensation of chromatin in nucelus of a cell undergoing necrosis/apoptosis
Karyolysiscomplete dissolution of the chromatin of a dying cell due to endonucleases
Karyorrhexisdestructive fragmentation of the nucleus of a dying cell whereby its chromatin is distributed irregularly throughout cytoplasm


Types of Necrosis
Question Answer
Coagulativecell death caused by ischaemia / infarction (Ex. ischaemic kidney)
Fatpseudomass that may develop w/n breast, present as a lump after breast surgery
Liquefactive/colliquativetransformation of tissue into liquid viscous mass (Ex. cerebral infarct)
Caseatingdead tissue appears as a soft and white proteinaceous dead cell mass (Ex. TB granuloma)


Skin layers from superficial to deep
Question Answer
Stratum corneummost superficial, apoptosis occurs
Stratum lucidumonly present in thick skin
Stratum granulosumcontain keratohyalin granules and lamellar bodies
Stratum spinousumkeratin filaments connected by desmosomes
Stratum basaledeepest, contains stem cell(keratinocytes), mitosis


Cell types in Epidermis
Question Answer
Melanocytesproduce melanin that is packaged into melanosomes, UV protection and skin pigmentation
Langerhan cellsAPC of skin, arise in bone marrow
Merkel cellsfine touch


Dermis (contains vessels, lymphatics nerve and nerve endings)
Question Answer
Papillaryright beneath epidermis, loose connective tissue made of collagen and elastin.
Reticularmajority of dermis, dense connective tissue with thick collagen, contains fibroblast and immune cells, site of skin appendages


Question Answer
sweatsimple tubular
Sebaceouscompound acinar


Wound healing in dermis:
Question Answer
Haemostasisstop bleeding by forming fibrin clots
Inflammationremoval of bacteria and damaged tissue
Fibroplasiafibroblast produces collagen + angiogenesis
Epithelialisationmigration and mitosis of keratinocytes to form new basal layer
Remodelingtissue replaced by stronger ones


Causes of oedema
Question Answer
increase in hydrostatic pressureLt and Rt HF, increase Na+ and H2O retention/ increase RAAS due to renal problem
decrease in oncotic pressureliver cirrhosis, malnutrition
lymphatic blockadeelephantiasis (lymph node blocked by parasite), obstruction by malignancy


Types of Shock
Question Answer
cardiogenicMI, AF, PE with outflow obstruction
hypovolemicsevere burn and haemorrhage
septicinfection commonly due to gram -ve(LPS activating immune system leading to systemic vasodilation, subsequent vascular leakage)
neurogenicsevere damage to CNS, SC injury
anaphylacticallergic reactions


Types of thrombi
Question Answer
arterial thrombimural and occlusive, driven by platelet, treat with anti-platelet
Venous thrombichanges in blood flow (stasis), driven by fibrin, treat with anti-coagulants


Question Answer
Systematicasso/ with HF + oedema
localcompression of blood vessels