Cellular adaptations simple

Question 1

In response to physiological and pathological stimuli, cells can

Answer 1

undergo changes which make them more suited for their environment.

Question 2

Hypertrophy

Answer 2

is the increase in the size of a tissue via the enlargement of cells

Question 3

physiological cause of hypertrophy

Answer 3

increased skeletal muscle mass gained through anabolic metabolism following exercise

smooth muscle hypertrophy occurs in the uterus stimulated by hormonal changes

Question 4

pathological cause of hypertrophy

Answer 4

hypertension causes pathological hypertrophy of the cardiac tissue-increased strain on the ventricles and atria fo the heart

Question 5

too much cardiac hypertrophy results in

Answer 5

the muscular walls of the heart being too thick to effectively pump blood through the body causing heart failure

Question 6

Hyperplasia

Answer 6

is the increase in the size of a tissue by an increase in the number of cells in that tissue.

Question 7

physiological cause of hyperplasia

Answer 7

1) Occurs in the endometrium of the uterus upon stimulation of oestrogen during the menstrual cycle.
2) Hyperplasia is also the method by which the liver restores itself from a partial resection.

Question 8

pathological cause of hyperplasia

Answer 8

can occur in overstimulation of endometrial tissue with oestrogen, for example in women taking unopposed oestrogen (without progesterone) for hormone replacement therapy after the menopause. The increased cell replication increases the chance of dysplasia (discussed later), and then neoplasia, taking place.

Question 9

atrophy

Answer 9

is the opposite of hyperplasia and hypertrophy, in essence, it is the shrinkage of tissue.

This can happen by a decrease in cell number and/or cell size.

Question 10

physiological atrophy

Answer 10

involution

Question 11

involution

Answer 11

when a tissue reduce in size after having increased in size.

Question 12

example of involution

Answer 12

For example, the uterus and breasts both reduce in size post-pregnancy.

Question 13

another example of physiological atrophy

Answer 13

Atrophy will also occur with old age. When an individual gets older, most systems and tissues undergo some level of atrophy.

Question 14

pathological cause of atrophy

Answer 14

malnutrition (catabolic metabolism)

inactivity

pressure

ischaemia

chronic inflammation.

Question 15

malnutrition (catabolic metabolism) cause

Answer 15

caused by diseases such as cancer or by nutritional deficit.

Question 16

Metaplasia

Answer 16

is the transformation of tissue from one type of cell to another, for example a squamous epithelial cell to a cuboidal epithelial cell.

Question 17

example of physiological metaplasia

Answer 17

squamous metaplasia that occurs in the cervix.

Question 18

squamous metaplasia that occurs in the cervix.

Answer 18

When the cervix everts, the columnar epithelium that lines it meets the acidic environment of the vagina. The epithelium undergoes metaplasia to become stratified squamous epithelium like the rest of the vagina as this is better suited to the conditions. The area where this metaplasia happens is called the transformation zone.

Question 19

pathological metaplasia occurs in response to

Answer 19

chronic stimulation from chemical or physiological factors

Question 20

metaplastic cells r often considered to be

Answer 20

precancerous since they can progress to form malignant cells

Question 21

metaplasia is a …… process

Answer 21

reversible

there is a chance that the cells will regress to their original type of the stimulus is removed

Question 22

examples of pathological metaplasia

Answer 22

• cigarette smoking

- barretts oesophagus

Question 23

metaplasia and cigarette smoking

Answer 23

Transformation of the pseudostratified columnar epithelium of the bronchi to stratified squamous epithelium in smokers due to cigarette smoke.

Question 24

Barrets oesophagus

Answer 24

Stratified squamous epithelium at the bottom of the oesophagus transforms to gastric glandular epithelium with persistent acid reflux.

• can occur due to a gastric hernia

Question 25

Dysplasia

Answer 25

is disordered growth of epithelium characterized by frequent mitotic figures and loss of cell orientation and uniformity (size, shape).

Question 26

dysplasia can progress to become

Answer 26

malignant (known as carcinoma in situ

Question 27

difference between dysplasia and neoplasia (cell that is cancerous) is that

Answer 27

dysplasia is reversible if the stimulus is removed,w while neoplasia is not

Question 28

example of cause of dysplasia

Answer 28

human papilloma virus (HPV) can cause dysplasia of the cervix int he transformation zone

Question 29

anaplasia

Answer 29

Anaplasia is the progression of dysplasia to the point where the cells have mutated so much, they are no longer morphologically distinct from other differentiated cells types.

Question 30

aplasia

Answer 30

Complete failure of specific tissue or organ to develop

Question 31

aplasia is what sort of disorder

Answer 31

embryological developmental disorder

e.g. thymic aplasia and kidney aplasia

Question 32

hypoplasia

Answer 32

Underdevelopment or incomplete development of tissue or organ at embryonic stage- inadequate number of cells

Question 33

why is hypoplasia not the opposite of hyperplasia

Answer 33

hypoplasia is a congenital disorder and hyperplasia is not

Question 34

atresia

Answer 34

No orifice- failure for opening to form

congenital

Question 35

examples of atresia

Answer 35

pulmonary valve
anus
vagina
small bowel