3. Cell Injury

Question 1

Which of the following changes in cell/tissue structure have the possibility of being reversible injuries? (there is more than one answer) (MG)

A. Gross morphological changes
B. Ultrastructural changes
C. Biochemical alternations
D. Nuclear light microscopic changes

Answer 1

B. Ultrastructural changes
C. Biochemical alternations

A and D are signs of irreversible cell injury

Question 2

Loss of microvilli is an indicator for what type of cell injury? (MG)

A. Reversible
B. Irreversible
C. Neoplastic
D. Necrotic

Answer 2

A. Reversible

Question 3

A 22 year old man is severely depressed and decides to take his own life. He looks himself in his car in the garage and let it run. An hour passes and his mother finds him and calls 911. In the ER it is found that he has serve Hypoxia due to carbon monoxide poisoning. His weaken cell membranes have started to take in Ca+2 what will this Ca leak cause?

A. Free Radical injury
B. Hyperpolarization
C. Direct destruction of the Nucleus
D. Activation of cellular enzymes

RFA

Answer 3

Ans D. leak of Ca causes the activation of cellular enzymes

such as:

Phospholipase
Proteases
Endonucleases
ATPase

Question 4

A newborn girl is show to have a rare genetic defect of a protective mechanism against free radicals. Which of the following could she lack?

A. NAPH Oxidase
B. Myeloperoxidase 
C. Glutathione 
D. P450
E. CLL3

RFA

Answer 4

Ans. C Glutathione- Glutathione and catalase protect the body from free radicals

A & B NADPH Oxidase and Myeloperoxidase- create reactive oxygen species, lacking these would cause recurrent infection

D & E P450 and CCL3- CCL4 is converted by P450 into CLL3 which causes lipid peroxidation

Question 5

Which of the following will occur if lysosomes are damaged?

A. Latent toxic activation causing release of free radicals
B. Accumulation of misfolded proteins which leads to apoptosis
C. Decrease in ATP production effecting oxidative phosphorylation
D. Autophagic vascuoles fuse with lysosomes causing hydrolytic enzyme release
E. Release of ROS causing mutations and eventually cell death

SZ

Answer 5

Ans. D
Autophagic vascuoles fuse with lysosomes causing hydrolytic enzyme release, these will breakdown cellular components.

A. Latent toxic activation causing release of free radicals = damage to Smooth ER
B. Accumulation of misfolded proteins which leads to apoptosis = Smooth ER
C. Decrease in ATP production effecting oxidative phosphorylation = Mito
E. Release of ROS causing mutations and eventually cell death = Nucleus

Question 6

Which of the following would not cause ROS to be produced?

A. Cellular aging
B. Chemical and radiation injury
C. Microbial killing by phagocytosis
D. Ischemia-reperfusion injury
E. Hypoxia

SZ

Answer 6

Ans. E Hypoxia

Hypoxia causes a decrease in oxidative phosphorylation, leading to decrease ATP production, which causes cell injury.