1.2 Overview of Cell

Question 1

Cell

Answer 1

• Smallest functional unit of living individuals

- Changes in structure and function lead to damage in tissues, organs and organ systems.

Question 2

Cellular Response to Stress

Answer 2

Adaptation - Alterations that enable cells to maintain a steady state despite adverse conditions

Survival of cell depends on change in size an shape without affecting function.
Stimulus causing the change affects whether it is normal or abnormal

Question 3

Persistent Stress

Answer 3

Increased functional demand
Hypertrophy, Hyperplasia

Reversible cell injury
Atrophy, Metaplasia, Dysplasia, Storage

Question 4

Mild/Severe Stress

Answer 4

Mild - Reversible and cell will return to normal
Adaptive Severe - Will return to normal or adapted state
Unresolved Severe - Irreversible and cell becomes necrotic

Question 5

Atrophy

Answer 5

Cells decrease in size due to decreased protein synthesis or increased protein catabolism.

Question 6

Hypertrophy

Answer 6

Increased in cell size.

- Increase in cellular protein and oxygen consumption

Question 7

Hyperplasia

Answer 7

• Increase in number. Only capable through miotic division.

Question 8

Metaplasia

Answer 8

• Replacement of a mature cell with cells not normally found in that type of tissue. Cell maybe less mature or less differentiated.
• Reprogramming of undifferentiated stem cells in the same tissue undergoing change.
  (Response to chronic inflammation)

Question 9

Dysplasia

Answer 9

• Atypical Metaplasia
• Deranged cell growth
  (Cancer)

Question 10

Hypoxia

Answer 10

• Most common cause of cell injury
  (Inadequate oxygen, respiratory disease, ischemia, anemia, edema)
  Cellular response - Decrease in ATP (failure of sodium potassium pump) . Results in cell swelling and vacuolation.

Question 11

Reperfusion Injury

Answer 11

When circulation is restored from hypoxia, it may damage the cell further

Question 12

Damage of Lead

Answer 12

Kidneys - Lead filtered in kidneys can lead to hypertension
Brain - Can cause demyelination and cortical cell death.
Red Blood Cells

Question 13

Lead

Answer 13

Ingested through GI Tract and Lungs
- Systems targeted are Red Blood Cells, GI Tract, Kidneys, and Nervous System
(Cardinal sign is anemia)

Question 14

Apoptosis/Necrosis

Answer 14

Apoptosis - Programmed cell death

Necrosis - Death of a cell due to trauma or disease

Question 15

Liquefactive Necrosis

Answer 15

• Hydrolytic enzymes transform tissue into viscous liquid mass.
• Neurons and glial cells of the brain are commonly affected.
• Due to fungal or bacterial infection

Question 16

Coagulative Necrosis

Answer 16

Results from hypoxia and severe ischemia or chemical injury

- Common in Kidneys, Heart, and Adrenal Glands

Question 17

Caseous Necrosis

Answer 17

• Results from TB

- Combination of coagulative and liquefactive necrosis.

Question 18

Dry Gangrene

Answer 18

• Insufficient blood supply (Arterial lumens are narrowed due to cholesterol plaques)
• Slow spreading, and line of demarcation
• Affected area become dry and shrink
• Color is dark brown/black

Question 19

Wet Gangrene

Answer 19

• Results from bacterial invasion.
• Rapid tissue destruction
• No line of demarcation, cold, swollen, pulseless tissue
  (Blisters, foul odor)
  May effect internal organs and extremities

Question 20

Gas Gangrene

Answer 20

• Type of wet gangrene
• Clostridium bacteria produces enzymatic toxins that dissolve cells. Massive spreading edema, RBC hemolysis, leads to renal failure
• Glucose from cells are fermented causing gas to be released from muscle tissue
• Amputation usually required