01 Growth Adaptation, Cellular injury, and cell death

Question 1

What causes Growth
adaptations?

Answer 1

An increase, decrease, or change in stress on an organ can result in growth
adaptations

Question 2

Mention all growth
adaptations (#7)

Answer 2

1. HYPERPLASIA
2. HYPERTROPHY
3. ATROPHY
4. METAPLASIA
5. DYSPLASIA
6. APLASIA
7. HYPOPLASIA

Question 3

Definition of hypertrophy

Answer 3

An increase in stress leads to an increase in organ size via an increase in the size cell (hypertrophy)

Question 4

Definition of hyperplasia

Answer 4

An increase in stress leads to an increase in organ size via an increase in the the number of cells (hyperplasia)

Question 5

What process are involve in Hypertrophy?

Answer 5

Hypertrophy involves gene activation, protein synthesis, and production of
organelles.

Question 6

What process are involve in Hypertrophy?

Answer 6

Hypertrophy involves gene activation, protein synthesis, and production of
organelles.

Question 7

What occurs in hyperplasia?

Answer 7

Hyperplasia involves the production of new cells from stem cells.

Question 8

What processes generally occur together, as exemplified in the uterus during pregnancy?

Answer 8

Hyperplasia and hypertrophy.

Question 9

Permanent tissues cannot make new cells (Hyperplasia) and undergo hypertrophy only. mention those tissues.

Answer 9

1. Cardiac muscle
2. Skeletal muscle
3. Nerve

Question 10

Give an example of pathologic hyperplasia and its potential progression.

Answer 10

Example - Endometrial hyperplasia. It can progress to dysplasia and eventually lead to cancer.

Question 11

Atrophy

Answer 11

A decrease in stress leads to a decrease in organ size

Question 12

Atrophy occurs via a decrease in the size and number of cells. How those two processes happen.

Answer 12

B. Decrease in cell number occurs via apoptosis.

C. Decrease in cell size occurs via ubiquitin-proteosome degradation of the
cytoskeleton and autophagy of cellular components

Question 13

Metaplasia

Answer 13

A change in stress on an organ leads to a change in cell type.

Question 14

How Metaplasia occurs?

Answer 14

occurs via reprogramming of stem cells, which then produce the new cell type.

Question 15

Is Metaplasia reversible?

Answer 15

Metaplasia is reversible, in theory, with removal of the driving stressor.

For example, treatment of gastroesophageal reflux may reverse Barrett
esophagus

Question 16

keratomalacia is an example of metaplasia, by deficiency of…

Answer 16

vitamin A deficiency, the thin squamous lining of the conjunctiva undergoes
metaplasia into stratified keratinizing squamous epithelium.

Question 17

Disordered cellular growth
B. Most often refers to proliferation of precancerous cells

Answer 17

Dysplasia

Question 18

Dysplasia arises from

Answer 18

Often arises from longstanding pathologic hyperplasia (e.g., endometrial hyperplasia) or
metaplasia (e.g., Barrett esophagus)

Question 19

Aplasia

Answer 19

is failure of cell production during embryogenesis.

(e.g., unilateral renal
agenesis).

Question 20

Hypoplasia

Answer 20

is a decrease in cell production during embryogenesis, resulting in a relatively small organ.

(e.g., streak ovary in Turner syndrome)

Question 21

when occurs Cellular injury?

Answer 21

Cellular injury occurs when a stress exceeds the cell’s ability to adapt.

Question 22

Hypoxia

Answer 22

Low oxygen delivery to tissue

Question 23

How occurs cellular injury by hypoxia?

Answer 23

1. Oxygen is the final electron acceptor in the electron transport chain of oxidative
   phosphorylation.
2. Decreased oxygen impairs oxidative phosphorylation, resulting in decreased ATP
   production.
3. Lack of ATP (essential energy source) leads to cellular injury.

Question 24

Causes of hypoxia

Answer 24

1. Ischemia
2. hypoxemia,
3. Decreased O2 -carrying capacity of blood.

Question 25

Ischemia

Answer 25

is decreased blood flow through an organ.

Question 26

Hypoxemia

Answer 26

is a low partial pressure of oxygen in the blood (Pao2
< 60 mm Hg, Sao2 < 90%).