How cells respond to injury

Question 1

In tissue when required or during injury what are labile and stable cells able to do?

Answer 1

• go through mitosis
• proliferate in cell number and then can differentiate

Question 2

What is hypertrophy and hypoerplasia?

Answer 2

• hypertrophy = cells get bigger
• hyperplasia = cell numb er increases

Question 3

What is apoptosis?

Answer 3

• programmed cell death

Question 4

In terms of proliferating ability, what are the 3 types of cells?

Answer 4

• labile = continually replication in mitosis
• stable = can go through mitosis, but need to be stimulated
• permanent = unable to go through mitosis

Question 5

What are the stages of a cell cycle?

Answer 5

• G0 = checkpoint stage
• G1 = growth stage
• S = DNA replication stage
• G2 = growth stage
• Mitosis = cell replication, including cytokinesis

Question 6

What is neoplasia?

Answer 6

• rapid abnormal cell growth

Question 7

What is atrophy?

Answer 7

• reduction in cell number

Question 8

What is metaplasia?

Answer 8

• cell differentiates into a different type of cell
• due to stimulus, such as in Barretts osophagus

Question 9

If a cell is damaged or stressed in a specific way, some cells are able to adapt to the stimulus. What are the 4 types of adaptation that are possible?

Answer 9

1 - hypertrophy

2 - hyperplasia

3 - atrophy

4 - metaplasia

Question 10

Give an example of phsyiological hypertrophy which is reversible?

Answer 10

• muscle size increases in training
• uterus change in size when a woman is pregnant (in figure)

Question 11

Give an example of pathological hypertrophy that is not reversible?

Answer 11

• left ventricular hypertrophy
• heart stressed due to hypertension and hypertrophy occurs
• can cause cardiac problems

Question 12

Give an example of physiological hyperplasia that is reversible?

Answer 12

• mammary glands in breast tissue
• number of mammary glands increase to prepare for baby

Question 13

Give an example of pathological hyperplasia that is not reversible?

Answer 13

• may be caused by hormonal imbalance
• gynomacostia or prostate hyperplasia

Question 14

Give an example of physiological atrophy?

Answer 14

• thymus shrinks and becomes fibrotic as no longer needed

Question 15

Give an example of physiological atrophy?

Answer 15

• muscle loss due to inactivation or neurological disease

Question 16

Give an example of physiological metaplasia?

Answer 16

• cells of cervical simple columnar epithelium to stratified squamous epithelium
• can be due to facing outside of body and exposure to stimuli

Question 17

Give an example of pathological metaplasia?

Answer 17

• barrett’s oesophagus change from sqaumous to columnar cells due to exposure to HCl

Question 18

If a cell cannot adapt, what things could happen?

Answer 18

• cell inhury that leads to death

Question 19

What is necrosis, and how does it differ from apoptosis?

Answer 19

• form of cell death that is always patholigcal
• apoptosis can be phsyiological or pathological

Question 20

When a cell undergoes apoptosis or necrosis, which cell balloons and which one shrinks?

Answer 20

• necrosis cells blow up
• apoptosis cells shrink

Question 21

When a cell undergoes apoptosis or necrosis, which cell can tends to cause inflammation?

Answer 21

• necrosis

Question 22

Give an example of physiological apoptosis?

Answer 22

• GIT epithelial cells
• cells are shedded when they reach the top of the villi

Question 23

Give an example of pathological apoptosis?

Answer 23

• glomerula dieing in end stage renal disease

Question 24

What is autophagy?

Answer 24

• natural, conserved degradation of cells or cellular components
• done to make new cells or remove aspects of cells which as not required