Cell Adaptation & Injury (L2)

Question 1

Define hypertrophy

Answer 1

Increase in cell size and function.

Question 2

Define hyperplasia.

Answer 2

Increase in the number of cells.

Question 3

Atrophy

Answer 3

Decrease in cell size and function

Question 4

Metaplasia

Answer 4

Change from a specialized cell type to less specialized one or to one that is needed to allow it to stabilize and injury.

Question 5

True or false? Hypertrophy and hyperplasia cannot occur simultaneously in tissues.

Answer 5

False. They CAN occur simultaneously as cells adapt to a stress or increased workload.

Question 6

Define atrophy. What are its causes?

Answer 6

Decrease in size and function of cells.
Causes:
-deficient nutrients
-decreased workload
-lack of stimulus (disuse, enervation, loss of hormone)
-increased pressure
-senility
-drugs: corticosteroids

Question 7

True or false? Atrophied cells are no longer living.

Answer 7

False! Atrophied cells are still alive with reduced function.

Question 8

Atrophied cells have a ________ in protein synthesis, _________ in protein degradation, __________ in autophagy process and autophagic vacuoles within atrophied cells.

Answer 8

Atrophied cells have a DECREASE in protein synthesis, INCREASE in protein degradation, INCREASE in authophagy process and autophagic vacuoles within atrophied cells.

Question 9

True or false? During metaplasia, the original cells are modified genetically.

Answer 9

False. The original cells are NOT modified genetically; stem cells are reprogrammed.

(Ex: ooseous metaplasia) age related lesion

Question 10

What process is considered “new growth” that is poorly controlled. Process where cells undergo genetic changes uncontrollably.

Answer 10

Neoplasia

Question 11

What process involves resulting cells are normal appearing, have normal genes, and growth is still controlled by normal processes.

Answer 11

Metaplasia

Question 12

Cell injury results when ______ has been exceeded

Answer 12

Adaptation

Question 13

5 factors that determine whether an injury is reversible or irreversible.

Answer 13

• type of cell
• type of injury
• severity
• duration
• multiplicity of injurious agents

Question 14

There are 9 causes of cell injury. Name 5.

Answer 14

• oxygen deprivation
• overwork
• aging
• genetic changes
• infectious agents

Question 15

Acute cellular swelling which is REVERSIBLE cell injury (hydropic degeneration) occurs when?

Answer 15

When the normal cell membrane homeostasis is disrupted from the loss of normal function of sodium/potassium pump.

• reduced oxygen tension
• direct membrane damage
• reduced ATP availability

Question 16

Necrosis is _____ cell death.

Apoptosis is _____ cell death.

Answer 16

Necrosis is accidental cell death. Apoptosis is programmed cell death.

Question 17

During necrosis, the nucleus changes as follow. What are the pathological names for each of the following?

1. Shrink and condense
2. Break into components
3. Fade away (dissolve)

Answer 17

1. Pyknosis
2. Karyorrhexis
3. Karyolysis

Question 18

In what 3 scenarios does apoptosis occur?

Answer 18

• DNA damage
• Accumulation of misfolded proteins
• Cell death in viral infections

Question 19

What are the two pathways that apoptosis is activated by?

Answer 19

• intrinsic (mitochondrial)

- extrinsic (death receptor)

Question 20

What is the intrinsic mechanism of apoptosis?

Answer 20

-cell injury or loss of growth factors causes release of cytochrome C from mitochondria and activation of caspase cascade.

Question 21

Describe the extrinsic mechanism of apoptosis.

Answer 21

-external stimulus interacts w/ the “death receptor” activating a different caspase cascade.

Question 22

What is the caspase cascade?

Answer 22

Initiator caspases activated through intrinsic or extrinsic mechanism

Question 23

What to executioner caspases do?

Answer 23

Activate endonuclease that fragments DNA and protease breaks down cytoskeleton.

• cells shrink, nucleus condenses and DNA fragments
• cytoplasmic organelles remain intact
• cytoplasm blebs
• blebs break off and contain normal organelles and nuclear fragments (apoptotic bodies)
• apoptotic bodies phagocytized by local macrophages, fails to stimulate inflammation

Question 24

True or false? Apoptosis usually does not produce gross changes in tissues.

Answer 24

True