disorders of growth

Question 1

response of cell to disease/injury depends on

Answer 1

how much injury

how vulnerable the cell is to injury

Question 2

responses of cell to stress

Answer 2

adaptation

injury

Question 3

cell injury

Answer 3

• where the dose is too large and the cell cannot adapt

- irreversible damage

Question 4

cell adaptation

Answer 4

metabolic

structural

Question 5

atrophy

Answer 5

decrease in cell size

decrease in cell number

Question 6

hypertrophy

Answer 6

increase in cell size

Question 7

hyperplasia

Answer 7

increase in cell nuumber

Question 8

metaplasia

Answer 8

change in how they differentiate

Question 9

labile cells

Answer 9

cells continually divide

in cell ccle

Question 10

permanent cells

Answer 10

after development they have left cell cycle
no longer can divide
if injured or die cannot be reaplced

Question 11

quiescent cells

Answer 11

cells that are not normally dividing

retained ability to divide

Question 12

too much growth causes

Answer 12

1) Developmental
- hamartoma
2) Reactive/adaptive
- hyperplasia
- hypertrophy

Question 13

hartoma

Answer 13

tumour like overgrowth
- tissues are normal for sit but excessive
stop growing after growth period

Question 14

what does hyperplasia occur to and lead to

Answer 14

response to stimulus
regression once stimulus removed
increased size and function

Question 15

chronic irritation/inflammation effects

Answer 15

lots of inflammatory mediators

causes cells to divide

Question 16

endocrine hyperplasia

Answer 16

1) Physiological
- normal growth and development
- puberty and pregnancy
2) pathological
- parathyroid (glands in the neck, produces hormones)
- thyroid

Question 17

ventricular hypertrophy

Answer 17

• heart has to work harder to pump the blood around the body
• therefore the heart has to increase its muscle cell size to pump the blood around the body
• muscle wall of the LHS increases in thickness in attempt to push against the high BP
• This can become pathological when the heart is as big as it can get

Question 18

neoplasia

Answer 18

growth which is uncontrolled and does not stop and persists after the stimulus has moved
(hyperplasia/trophy is under normal conditions when stimulus is removed returns to normal)

Question 19

developmental conditions with too little growh

Answer 19

agenesis
aplasia
hypoplasia

Question 20

agenesis

Answer 20

extreme of too little growth at all

e.g. missing 3rd molars

Question 21

aplasia

Answer 21

forms but not to its full structure

Question 22

hypoplasia

Answer 22

structure forms but it is deficient in its capacity

e.g. enamelhypoplasia

Question 23

mechanisms of atrophy

Answer 23

imbalance of cell loss and production

• reduced proliferation
• apoptosis rather than necrosis
• reduction in structural components of the cell esp protiens

Question 24

generalised atrophy

Answer 24

1) Nutritional
- starvation
- start to break down the tissues, fat and muscle
2) Age related(senile)
- with age tend to shrink a bit
3) Endocrine
- usually due to removal of hormone
- eg reduction in levels of oestrogen during menopause
- leads to generalised atrophy of bone
4) Bone
- osteoporosis
- density of the trabeculae bone is reduced

Question 25

localised atrophy

Answer 25

1) Ischaemic - reduction in blood supply to organ or part of the body 2) pressure - sustained pressure at a part in the body - eg pressure sores from being immobile for a period of months 3) disuse - reduction in muscle mass as they are not being used 4) neuropathic/denervation - reduction in muscle mass as they are not being used - nerve damage can lead to a reduction in the muscle the nerve supplies 5) immune mediated (autoimmune) - body raises an immune repsonce to a specifc tissue 6) Idiopathic - cause unknown

Question 26

atrophic mandible issues

Answer 26

without teeth alveolar bone will shrink back | harder to place a denture on the ridge

Question 27

metaplasia

Answer 27

change in differentiation - change within the same germinal layer results from environmental demands

Question 28

example of metaplasia

Answer 28

mucus metaplasia e.g. squamous metaplasia in brooch of smokers due to irritation of smoke, not usually sqamous prevention of original job to secrete mucus and cilia

Question 29

dysplasia

Answer 29

Abnormal growth and differentiation in a tissue with abnormal cells and tissue architecture - May be premalignant, higher risk of becoming cancer - overall growth of the cell is abnormal

Question 30

ectopia

Answer 30

Tissue gets to the wrong place - developmental abnormality - normal tissue, abnormal site