Cell + tissue changes in disease Flashcards
(32 cards)
why is tissue homeostasis important?
for tissue maintenance and function
cellular changes in disease
changes in environment may require cell to adapt
physiological stressors or pathological stimuli
physiological stressors
ageing
lifestyle changes
diet changes
environmental
pathological stimuli
- hypoxia
- toxic injury
- microbial pathogens
- radiation
- genetic
- immune response
changes in tissue structure
and due to
- too little cell division
- increase cell division
- metastasis
- abnormalities in tissue differentiation
due to physiological or pathological trigger
agenesis
when part of organ or complete absence of organ completely fails to develop from the start eg kidney
absence of cells within an organ
aplasia
structure started to develop but failed to grow- anlage/ rudiment that never developed
eg lung where bronchus ends blindly
anlage- earliest version of organ
hypoplasia and example
- organ did form but is under eloped such as smaller
- micropthlamia is smallness of eyes
dysgraphics
- birth defects caused when two or more structures in the embryo don’t fuse together like they should.
- eg spina bifida- spinal bones don’t close over spinal cord
atrophy
- shrinking of cell size due to loss of substance
- disease
- diminished blood supply
- poor nutrition
- muscle atrophy- muscles get smaller
- decreased cell division
- increased cell apoptosis
is atrophy always pathological?
no
can also be physiological such as
thymus
embryology
ageing- ovaries
hypertrophy
physiological and pathological
- increased cell size and increase in size of organ
physiological: muscles growing bigger in exercise, uterus gets bigger to support baby
pathological: cardiac hypertrophy, high bp, heart thickens and harder to pump blood can lead to heart failure
hyperplasia physiological and pathological
- increase in NUMBER of cells or organ or tissue
- ## physiological- uterus linen thickens
metaplasia
conversion of one differentiated cell type to another
- replacement of glandular epithelium (mono layer) with squamous stratified multi layer
- happens as response to injury or stress and can be reversible but if not it become DYSPLASTIC
dysplasia
- abnormal development or growth of cells, tissues or organs
- irregular changes in size, shape and organisation
- squamous epithelium
- pre-neoplastic lesion ( can be cancerous if untreated)
in-situ
in the same place so these cancerous cells are staying in the same place and haven’t become invasive yet and spread to other tissues
carcinoma insitu and changes
- precancerous condition where abnormal cells are found in tissue lining but have not yet spread
- changes are increases mitosis. changes in cell size and shape etc and disorder of cells(arrangement)
development of cervical carcinoma
- normal columnar in endocervical lining and normal squamous in ectocervix change to squamous epithelium
- which is called metaplasia ( can also be called squamous metaplasia)
- then undergoes dysplasia, abnormal cell growth
- leading to carcinoma insitu
- which can then become invasive carcinoma- metasis
metastasis
- carcinoma will become invasive when it’s broken through basement membrane that underlies it
- moves through extra cellular matrix
- enter blood and lymphatic vessels to invade other parts of body or tissue/organ
- survives within circulation
- exits circulation by exiting capillaries and arrives at new site
- survives and grows as metastasis at other sites and can form new tumours in other parts of body
neoplasm
cancer
new growth
tumour
characteristics of cancer
abnormal cells
uncontrolled growth
dna mutations
cancers classified by tissue type
carcinoma
epithelial
cancers classified by tissue type
sarcoma
solid tumours
connective tissue
cancers classified by tissue type
leukemias and lymphomas
circulatory or lymphatic systems
