1. Tissues for electron microscopy are fixed in:
a) Carnoy’s fixative
b) 10% buffered formalin
c) 4% glutaraldehyde
d) Saline
2. The DNA molecule is a double helical strand having the following nucleotide bases:
a) Cytosine, thymine, alanine, guanine
b) Adenine, guanine, valine, thymine
c) Cytosine, lysine, adenine, guanine
d) Adenine, guanine, cytosine, thymine
3. Actin and myosin proteins are found in:
a) Microtubules
b) Microfilaments
c) Intermediate filaments
d) Ribosomes
4. The major mechanism of damage to plasma membrane in ischaemia is:
a) Reduced intracellular pH
b) Increased intracellular accumulation of sodium
c) Increased Ca++ ions in the cytosol
d) Reduced aerobic respiration
5. In ischaemia-reperfusion cell injury, there are:
a) Increased Ca++ ions in the extracellular fluid
b) Increased Ca++ ions in the cytosol
c) Ca++ ions are equal in the cytosol and in extracellular fluid
d) Ca++ ion equilibrium is unaffected
6. Out of various free radical species, the following radical is most reactive:
a) Superoxide (O2’)
b) Hydrogen peroxide (H2O2)
c) Hydroxyl (OH–)
d) Nitric oxide (NO)
7. In fatty liver due to chronic alcoholism, the following mechanisms are involved except:
a) Increased free fatty acid synthesis
b) Decreased triglyceride utilization
c) Increased α-glycerophosphate
d) Block in lipoprotein excretion
8. The following pigments are stainable by Prussian blue reaction except:
a) Haemosiderin
b) Ferritin
c) Haemochromatosis
d) Haematin
9. Enzymatic digestion is the predominant event in the following type of necrosis:
a) Coagulative necrosis
b) Liquefactive necrosis
c) Caseous necrosis
d) Fat necrosis
10. Mechanism of mammalian apoptosis involves the most important role of the following protein:
a) Receptor for TNF
b) BCL-2
c) TP53
d) CED-9