Day 1 Flashcards
What is hyperplasia?
An increase in cell number - occurs due to stimulus
What happens to cell number if the hyper plastic stimulant is removed?
growth regresses back to norm
Give examples of hyper plastic responses.
The lining of the uterus (endometrium) stimulated by hormones during periods
Liver regeneration after resection
Smooth muscle can undergo hyperplasia.
True/False?
False
hypertrophy not hyperplasia
What is hypertrophy?
increase in cell size
more organelles in the cytoplasm since more is being asked of the cell
Which types of muscle undergo hypertrophy?
skeletal and cardiac
Give an example of hypertrophy of cardiac muscle.
Left Ventricular Hypertrophy
What is atropy?
decrease/loss in cell size ± number
When does atropy occur?
when stimulus is withdrawn
Give examples of atropy.
astronauts’ muscles waste since not using them
plaster cast - muscles in cast not used
What is metaplasia?
Reversible change of one mature cell type to another (mature type)
Which type of epithelium is most commonly exposed to external environment?
squamous
Give detailed examples of metaplastic change.
Barrett’s oesophagus: oesophageal squamous -> intestinal columnar
Smoking: ciliated pseudo-stratified columnar cells of bronchus -> squamous epithelium
Is it normal to find goblet cells in Barrett’s oesophagus?
Yes, they secrete mucin which tries to protect the oesophagus from acid reflux
Keratinised epithelium is red, shiny and found on the outside of the body.
True/False?
True that it is outside
False it is not red and shiny, but pink and hard
Where would you find non-keratinised epithelium?
the oral cavity, very end of nose
What is neoplasia?
New growth (without stimulus)
Neoplasia is not a term for cancer, but can it be malignant?
Yes.
Neoplasms can be benign, pre-malignant or malignant
Give an example of a pre-malignant neoplasm
colorectal adenomas
Give an example of a purely benign neoplasm
squamous papilloma
Is squamous dysplasia benign or malignant?
It is graded according to severity - it may be benign but with dysplastic potential.
Carcinoma in-situ is the best prognostic type of squamous dysplasia.
True/False?
False.
Carcinoma in-situ represents severe abnormality and is the closest to becoming full blown malignancy.
What is the definition of a cyst?
An abnormal closed, epithelium-lined sac that contains liquid or a semi-solid substance.
If a cyst is not lined with epithelium, what is it called?
pseudo cyst
lined by pseudo-stratified cells
