MOD 6-9 Flashcards Preview

ESA 2 > MOD 6-9 > Flashcards

Flashcards in MOD 6-9 Deck (88)
Loading flashcards...

What is pleomorphism?

More mitosis figures and increasing variation in size and shape of cells - seen in malignant neoplasm.


Describe the alterations to DNA which cause neoplasm

Initiators and promoters needed resulting in monoclonal growth which, through progression, accumulates more mutations.


What is lyonisation?

One x is randomly inactivated during early embryogenesis


Distinguish between in situ and invasive malignancy

In situ- no invasion through basment membrane


What is an adenoma?

Benign, glandular origin, epithelioial


What is a papilloma?

Benign tumour which projects out wards


What is a carcinoma?

Malignant tumour of epithelial cells


What is a sarcoma

Malignant, stromal cells


What is the most crucial check point in the cell cycle

The restriction (r) point towards the end of G1


How is the cell cycle controlled?

Check points at the end of each growth phase.
Levels of cyclins regulate processes and control transitions between stages as well as the speed. They act by binding to CDks to form active kinases.


What is the difference between regeneration and reconstruction?

Regeneration is more cells. Reconstruction is the replacement of a lost part of the body e.g. Babies fingers.


How does the body increase the rate of cell proliferation?

Growth factors e.g. Epidermal growth factor.
Binds to receptors which triggers gene transcription. Shortens cell cycle and takes stable cells out of G0. Also affects differentiation, activation, angiogenesis, locomotion ect.


What type of cells does hypertrophy occur?

Mainly permanent but may occur in any


What causes hypertrophy (generally)?

Functional demand or hormone stimulation


Physiological examples of hypertrophy

Skeletal muscle, pregnant uterus, compensatory e.g. Removing a kidney.


Pathological examples of hypertrophy

Ventricular hypertrophy, bladder outlet obstruction-SM hypertrophy.


Give examples of physiological hyperplasia

Endometrium under influence of oestrogen. Bone marrow produces erythrocytes in response to hypoxia.


Give pathological examples of hyperplasia

Goitre and eczema


Give pathological examples of atrophy

Osteoporosis, tissues around a tumour due to ischemia, loss of blood supply, cerebral atrophy in Alzheimer's, loss of nutrients, loss of innervation to muscle, persistent injury - polymyositis (inflammation of muscle), aging


Give a physiological example of atrophy, what can this be called?

Ovarian atrophy in post menopausal women (technically involution - programmed cell shrinkage) thymus


What is hypoplasia?

Underdevelopment of an organ or tissue in the embryonic stage due to inadequate number of cells.
It is congenital - not the opposite of hyper.


What is the difference between aplasia and hypoplasia?

Aplasia is the complete failure of an organ or tissue to develop, hypo is partial.
Aplasia is also used to describe an organ whose cells nolonger proliferate e.g. Bone marrow.


What is metaplasia

Reversible changes of one cell type to another.
Not across germ layers.
Fully differentiated in response to stress.
May lead to cancer


Give examples of pathological metaplasia

Smoking epithelium changed to stratified (bronchial).
Gastric glandular columnar epithelium instead of stratified squamous with persistent acid reflux.


What is atresia?

When a hole doesn't open


Define an atheroma

The accumulation of intra and extracellular lipid in the intima and media of large and medium sized arteries.


Define atherosclerosis

Thickening and hardening of arterial walls due to An atheroma


What is arteriosclerosis

Thickening of arterial walls due to DM or hypertension.


Describe the macroscopic appearance of an atheroma

Starts as fatty streak - lipid deposits in intima, slightly raised.
Then becomes a simple plaque - deposits are more widespread with an irregular outline, enlarge and coalesce.
Can become a complicated plaque which involves thrombosis, haemorrhage into plaque, calcification or aneurysm.


Describe the early and later changes in the microscopic appearance of an atheroma.

Early - SM cells proliferate and foam cells accumulate, extracellular lipid.

Late- cholesterol deposits and clefts(in tissue too), possibly inflammatory cells, fibrosis, necrosis.