Q- Which of the following differentiates Dubin-Johnson syndrome from Rotor syndrome?
A- Black pigmentation of the liver
B- Conjugated hyperbilirubinemia
C- Level of liver enzymes
D- Mode of inheritance
A- Black pigmentation of the liver- Both Dubin–Johnson and Rotor syndromes cause conjugated hyperbilirubinemia and have similar inheritance patterns. The key distinguishing feature is that Dubin–Johnson syndrome shows dark, black liver pigmentation, while Rotor syndrome does not.
Q- At which of these vertebral levels does the trachea bifurcate?
A- Seventh cervical
B- First thoracic
C- Fourth thoracic
D- Sixth thoracic
C- Fourth thoracic- The trachea bifurcates at the T4–T5 level, also known as the sternal angle (Angle of Louis). This is the classic anatomical landmark for the carina.
Q- Which one of the following proteins surrounds the nuclear envelope?
A- Actin
B- Enkephalin
C-Tropomyosin
D-Vimentin
D-Vimentin- Vimentin is an intermediate filament protein found in mesenchymal cells and is closely related to the structural intermediate filaments that form the nuclear envelope framework (nuclear lamina). Actin and tropomyosin are associated with muscle contraction, and enkephalins are neuropeptides—not structural proteins.