Chapter 4 - Cell Injury and Death Flashcards
True or false: metaplasia is irreversible when injurious stimulation is removed
false - it’s reversible
What is apoptosis?
- programmed cell death
- not always pathologic
- used to
- control cell size numbers
- limit tissue size
- remove dangerous cells
- occurs in response to injury that does not directly kill cell
- triggers intracellular cascades
- activates cellular suicide response via caspases
What are the three main reactive oxygen molecules generated during an ischemic episode?
- OH-
- O2-
- H2O2
What is programmed senescene theory?
aging is the result of an intrinsic genetic program
What is nutrition excess?
- primarily result from excessive intake
- BMI greater than 27 kg health risk
- BMI greater than 30 kg obesity
What causes hytrophy?
- increased cellular protein content
- increased workload
- hormonal stimulation
What does this image show?
fat necrosis
What does irreversible injury consist of?
Two basic processes that underlie the morphologic changes of necrosis
- denaturation of protein
- enzymatic digestion of cell components
How do chaperone proteins limit protein damage?
Stress/mutation –> accumulation of misfolded proteins –> synthesis of chaperones –> repair
What are common causes of malnutrition?
- poverty
- chronic alcoholism
- acute and/or chronic illness
- self-imposed dietary restrictions
- malabsorption syndromes
Which type of cells are capable of hyperplasia?
A) Skeletal muscle cells
B) Cardiac muscle cells
C) Epithelial cells
D) All of the above
C
Which of the following are reversible cell injury types:
A) intracellular accumulations
B) Hydropic Swelling
C) limiting protein damage
D) none of the above
____ is the most common type of necrosis
coagulative
What does this picture show?
- gas gangre
- results from infection of necrotic tissue by anerobic clostridium sp
- release hydrolytic enzymes that destroy cell membranes and connective tissue
- formation of gas bubbles in damaged muscle
- can be fatal due to lysis of RBCs
Clicker: Which type of irreversible injury initiates an inflammatory response?
A) Apoptosis
B) Necrosis
C) Hydropic swelling
D) Intracelliular accumulations
B
What happens if the cell is unable to maintain homeostasis in the face of injurious stimuli?
cell injury
Physiologic stresses or pathologic stimuli results in _________.
adaptation
Dysplasia is also known as ________
atypical hyperplasia
Bestowing to ischemia-induced cell injury, damage often occurs through the formation of _______.
reactive oxygen radicals
What is hyperplasia?
- increase in functional capacity related to an increase in cell number due to mitotic division
What is ischemia-reperfusion injury?
- damage occuring after blood supply to tissues has been restored
- components
- calcium overload
- formation of free radicals
- subsequent inflammation
What is gangrene (gangrenous necrosis)?
- death in a large area of a tissue from interupttion of blood supply to a particular part of the body
What is the free radical theory?
aging is a result of accumulated metabolic cell damage over time
What are intracellular accumulations?
- excess accumulations in cells
_____ is a type of necrosis that occurs in the pancreas
fat
Generalized swelling of cells in organs can lead to incease in size and weight called _______.
megaly
What does this picture show?
A) atrophy
B) hypertrophy
C) hyperplasia
D) metaplasia
E) dysplasia
E
What are the three types of gangrene?
- dry gangrene
- wet gangrene
- gas gangrene
What is this a picture of?
caseous necrosis
What does this picture show?
A) atrophy
B) hypertrophy
C) hyperpasia
D) metaplasia
E) dysplasia
A
Reduced endoplasmic reticulum, mitochondria and myofilaments are all cell changes due to:
A) atrophy
B) hypertrophy
C) hyperpasia
D) metaplasia
E) dysplasia
A
What is coagulative necrosis?
- arises from ischemic injury and metabolic acidosis due to hypoxic conditions
- dead cells form a gel-like consitency
- lower pH causes protein albumins to coagulate to form a jelly-like firm substance
What is dysplasia?
disorganized appearance of cells because of abnormal variation in size, shape and arrangement
What is ischemia?
- restriction in blood supply causing a shortage of O2 and glucose needed for cellular metabolism
- leads to lactic acidosis
- cell death occurs when plasma, mitochondrial, and lysosomal membranes become damaged
What are the mechanisms responsible for aging?
- DNA damage
- Reduced proliferative capacity of stem cells
- accumulation of metabolic change
What are the 5 mechanisms of cell injury?
- depletion of ATP
- mitochondrial damage
- influx of intracellular calcium and loss of calcium homeostasis
- accumulation of oxygen-derived free radical (oxidative stress)
- defects in membrane permeability
What is caseous necrosis?
- characteristic of lung damage secondary to tuberculosis
- resembles clumpy cheese
- cellular detail gone
During what phase of the uterine cycle does hyperplasia occur to the endometrial lining?
proliferative
What is infectious and immunologic injury?
- bacteria and viruses can injure cells depending on virulence
- added injury may occur indirectly by triggering body’s immune response