Ch. 1: Growth Adaptations, Cellular Injury, Cell Death

Question 1

What causes a growth adaptation?

Answer 1

An increase, decrease, or change in stress on an organ

Question 2

Hypertrophy

Answer 2

Increase in size of cells of organ

Question 3

Hyperplasia

Answer 3

Increase in number of cells of organ

Question 4

How does hypertrophy occur?

Answer 4

Gene activation, protein synthesis, and production of organelles

Question 5

How does hyperplasia occur?

Answer 5

Production of new cells from stem cells

Question 6

What tissues can only undergo hypertrophy? Why?

Answer 6

Permanent tissues (cardiac, muscle, skeletal muscle) because they cannot make new cells.

Question 7

Benign prostatic hyperplasia (BPH) exception?

Answer 7

Pathologic hyperplasia doesn’t increase risk of prostate cancer.

Question 8

Atrophy

Answer 8

Decrease in stress leading to decrease in organ size via a decrease in size and number of cells.

Question 9

How does decrease in cell size occur?

Answer 9

Ubiquitin-proteosome degradation (UPD) of cytoskeleton and autophagy of cellular components

Question 10

How does UPD occur?

Answer 10

Intermediate filaments of cytoskeleton are “tagged” with ubiquitin and destroyed by proteosomes

Question 11

How does autophagy occur?

Answer 11

Generate autophagic vacuoles that fuse with lysosomes with hydrolytic enzymes.

Question 12

Metaplasia

Answer 12

Change in cell type better able to handle a new stress.

Reversible in theory.

Question 13

What does metaplasia involve?

Answer 13

Commonly a change of one type of surface epithelium (squamous, columnar, or urothelial) to another.

Question 14

How does metaplasia occur?

Answer 14

Reprogramming of stem cells which produce new cell type.

Question 15

Dysplasia

Answer 15

Disordered cell growth usually from persistent pathologic hyperplasia.

Question 16

When does dysplasia become irreversible?

Answer 16

When it progresses to carcinoma

Question 17

Aplasia

Answer 17

Failure of cell production during embryogenesis

Question 18

Hypoplasia

Answer 18

Decrease in cell production during embryogenesis, resulting in relatively small organ.

Question 19

What is Potter Syndrome an example of?

Answer 19

Lung Hypoplasia

Question 20

When does cellular injury occur?

Answer 20

When stress exceeds the cell’s ability to adapt

Question 21

Ischemia

Answer 21

Decreased blood flow through an organ causing a shortage of oxygen.

Question 22

What does likelihood of injury depend on?

Answer 22

Type of stress, severity, and type of cell.

ie neurons more affected by ischemia than skeletal muscle

Question 23

What are common causes of cellular injury?

Answer 23

Inflammation, nutritional deficiency or excess, hypoxia, trauma, genetic mutations

Question 24

Hypoxia

Answer 24

Low oxygen delivery to tissue

Question 25

How does hypoxia cause cellular injury?

Answer 25

No oxygen to accept electron in ETC leading to decreased ATP

Question 26

Three causes of hypoxia?

Answer 26

Ischemia, hypoxemia, decreased O2-carrying capacity in blood.

Question 27

Hypoxemia

Answer 27

Low partial pressure of oxygen in blood

Question 28

What partial pressure of oxygen is considered hypoxemia?

Answer 28

PaO2 < 60 mm Hg

Question 29

What four circumstances can cause hypoxemia?

Answer 29

High altitude, hypoventilation, diffusion defect, and V/Q mismatch.

Question 30

What is a diffusion defect?

Answer 30

A thicker diffusion barrier prevents normal amount of O2 pushed into blood

Question 31

What are the two types of V/Q mismatch?

Answer 31

1) Circulation problem - Blood bypasses oxygenated lung | 2) Ventilation problem - oxygenated air cannot reach blood

Question 32

What causes decreased O2-carrying capacity?

Answer 32

Hemoglobin loss or dysfunction

Question 33

Classic finding of carbon monoxide poisoning?

Answer 33

Cherry-red appearance of skin

Question 34

Earliest sign of CO exposure?

Answer 34

Headache

Question 35

Three example of hemoglobin loss/dysfunction

Answer 35

1) Anemia (decrease in RBC mass) 2) CO poisoning 3) Methemoglobinemia

Question 36

What is Methemoglobinemia?

Answer 36

Iron oxidized to Fe3+ which CAN'T bind O2 | Fe2+ binds O2

Question 37

Two places you see methemoglobinemia?

Answer 37

1) Oxidant stress (sulfa or nitrate drugs) | 2) In newborns

Question 38

Hallmark of reversible injury?

Answer 38

Cellular swelling

Question 39

Hallmark of irreversible injury?

Answer 39

Membrane damage

Question 40

Two results of plasma membrane damage?

Answer 40

1) Cytosolic enzymes leaked into serum | 2) More Ca2+ into cell

Question 41

Two results of mitochondrial membrane damage?

Answer 41

1) Lose ETC (inner membrane). | 2) Cytochrome c leaking into cytosol

Question 42

What does cytochrome c in cytosol signal?

Answer 42

Apoptosis

Question 43

Result from lysosome membrane damage?

Answer 43

Hydrolytic enzymes leaking into cytosol activated by high intracellular Ca

Question 44

End result of irreversible injury?

Answer 44

Cell death