25. Statements about Bruch's membrane:
A- has five well defined layers
B-is penetrated by the choriocapillaries
C-is 2-4 mm thick
D-is secrated by the RPE
E-is absent at the fovea
25-the Trochlear nerve:
A-is vulnerable to head injury
B-passes between the posterior cerebral and the
superior cerebellar arteries
C-passes through the anterior medullary vellum
D-lies in the lateral wall of the cavernous sinus
E-innervates the superior oblique muscle on its
inferior surface
26. The following arteries make up the circle of Willis:
A-the anterior communicating artery
B-the internal carotid artery
C-the posterior cerebral artery
D-the basilar artery
E-anterior cerebral artery
27. The following structure arise from the neural crest:
A-optic nerve and its meninges
B-orbital bones
C-ciliary epithelium
D-sclera
E-lens epithelium
28. The lens zonules:
A-comprises of collagen type II and to a
lesser extent
type IV
B-are attached to the lens 2 mm anterior to the
equator
C-are attached to the valley areas of the ciliary
processes
D-cystine makes up 7% of their structure
E-are produced by the pars plicata of the ciliary
epithelium
29. The corneal endothelium:
A-is made up of 2-3 layers of cells
B-are squamous stratified cells
C-have tight junctions between cells
D-has a HCO3- pump
E-may maintain clarity of the cornea even when only
50% of its cell population are left
30. Histamine released by: macrophage , lymphokines , mast
cells , basophils , neutrophils
31. Ethiophate : Muscarinic blocker , used to treat lid lic
, lower IOP by suppressing aqueous production.
32. Which of these are not present in sarcoidosis : giant
cells , epitheloid cells , caseations , Shummas bodies.
33. Long term use of steroid (7.5 mg) can cause:
oligouria , muscle fasciculation , suppression of ACTH
release .
34. Which of these antibiotics act on the cell wall: penicillin , vancomycin
, sulphonamide , tetracycline , erythromycin , chloramphenicol.
35. Viruses: can result in host cell lysis ,
HIV : CD4 is a receptor for HIV , can transmit
from mother to foetus , antibodies can be detected within 3 months
of infection , can cause tumours.
36. Which of these drugs cause increased intracranial
pressure : steroids , azetazolamides , vitamin A ,
ethambutol , tetracycline .
37. First line treatment of endophthalmitis :
oral steroids , intravitreal vancomycin, oral
chloramphenicol , subconjunctival gentamycin ,
intravitreal gentamycin .
38. TB : BCG can be given to neonate , caseation may
contain live mycobacterium , can be diagnosed with
circulating antibodies easily , .
39. Tetanus : exposure to tetanus first time can cause
life long immunity , it can cause anaphylaxis reaction
, toxins produced by C perferinges.