1. The following are true (Ophthalmology):
* a) The HLA proteins are found within the cytoplasm of the cells
* b) HLA class I antigens are expressed on all cells with nuclei
* c) HLA class II antigens presents the virus infected cells to cytotoxic T lymphocytes
* d) HLA genes are found on chromosome 6
* e) HLA tissue typing is carried out in all forms of transplantation to prevent rejection
Answer a. F b. T c .F d. T e. F
2. True statements about chromosome include:
* a) There are 23 pairs of autosomal chromosome traits
* b) 23 chromosomes are found in germinal cells
* d) In female only one chromosome is activated
* c) The Barr body is due to inactivated X chromosome
* e) Klinefelter's syndrome result from an extra X chromosome in male
Answer a. F b. T c. T d. T e .F
3. The following are true about the DNA in mitochondria:
* a) They are found in the ovum and not the spermatozoan
* b) They have their own genome
* c) They are expressed in muscle cells
* d) An affected male with mitochondrial disorder can pass it on to his daughter only
* e) They are responsible for coding enzymes used in oxidation
Answer a. T b. T c. T d. F e. T
* a) Monoamine oxidase: noradrenaline
* b) Cholinesterase: acetylcholine
* c) Catechol-o-methyl transferase: dopamine
* d) Dopa decarboxylase: adrenaline
* e) Glutamic acid decarboxylase: gamma-aminobutyric acid (GABA)
Answer a. F b. F c. F d. T e. T
5. Recognized virulence factors in bacteria include:
* a) Ig A-proteases
* b) Beta lactamases
* c) gonococcal pili
* d) Streptococcal M protein
* e) The capsular polysaccharides in Haemophilus influenzae
Answer a. T b. F c. T d. T e.
6. The following are true about the viruses:
* a) They contain either RNA or DNA nuclei acids only
* b) HIV virus is a DNA virus
* c) Cytomegalovirus is a DNA virus
* d) All herpes viruses are sensitive to acyclovir
* e) Viral replication within the host cells is inhibited by interferons
Answer a. T b. F c. T d .F e. T
7. With regard to immunoglobulin A:
* a) It is the heaviest immunoglobulin
* b) It is the first immunoglobulin to be produced when the body is invaded by viruses
* c) It is secreted by the lacrimal gland
* d) It is secreted in the breast milk
* e) It is an effective defense against gonococcus
Answer a. F b. F c. T d. T e. T
* a) Arthus reaction is a type IV reaction
* b) Anaphylaxis occurs in patients who have had no previous exposure to the offending substance
* c) Contact dermatitis is a type IV reaction
* d) Positive Mantoux test is a type III reaction
* e) Urticaria is a type II reaction
Answer a. F b. F c. T d. F e. T
9. True statements about the nucleic acid include:
* a) Contains purine and pyrimidine which are bound together by covalent bonds
* b) There is always an equal concentration of purine and pyrimidine
* c) In RNA, thymine is replaced by uracil
* d) Introns is more common than exons on the DNA
* e) The histones mark the excision site
Answer a. F b. T c. T d. F e. F
10. At the adrenergic synapse, the concentration of adrenaline in synaptic cleft:
* a) Increased by cocaine which inhibit reuptake of adrenaline
* b) Decreased by MAO (monoamine oxidase) - inhibitors
* c) Controlled chiefly by the activity of the enzyme COMT
* d) Increased by noradrenaline receptor blockers
* e) Increased by partial agonist of noradrenaline receptors
Answer a. T b. F c. F d. T e. T
11. True statements about chloroquine include:
* a) Is safer than hydroxychloroquine at equivalent dose
* b) Can cause corneal deposition
* c) Causes posterior subcapsular cataract
* d) Chloroquine is bound to the melanin of the retinal pigment epithelium
* e) Causes reversible toxic maculopathy
Answer a. F b. T c. F d. T e F
12. Impaired accommodation occurs with
* a) Phenothiazine
* b) Topical pilocarpine
* c) Topical atropine
* d) Topical phenylephrine
* e) Topical cocaine
Answer a. T b. F c. T d. F e. T
13. The effects of topically applied anticholinesterase on the eye include:
* a) Conjunctival hyperaemia
* b) Raised intraocular pressure
* c) Ciliary muscle contraction
* d) Sphincter pupillae muscle relaxation
* e) Retraction of the upper lids
Answer a. F b. F c. T d. F e. F
14. Acetazolamide causes the following:
* a) Metabolic acidosis
* b) Hyperkalaemia
* c) Hypernatraemia
* d) Renal calculi
* e) Hypercalcaemia
Answer a. T b. F c. F d. T e. F
15. Following an acute inflammation, the following may occur:
* a) Complete resolution
* b) Abscess formation
* c) Chronic inflammation
* d) Scar tissue formation
* e) Loss of function
Answer a. T b. T c. T d. T e. T
16. The following virus is associated with human cancer:
* a) Herpes zoster
* b) Epstein-Barr virus
* c) Human papillovirus
* d) Hepatitis type A
* e) Human immunodeficiency virus
Answer a. F b. T c. T d. F e. T
* a) Is involved in botulism
* b) Elicit an antibody response, which may protect the host from future attack
* c) Is produced mainly by Gram positive bacterial
* d) Can often survive autoclaving
* e) Is found in the vesicle of bacterial cytoplasm
Answer a. F b. F c. F d. T e. F
* a) Fusidic acid is used in staphylococcus aureus infection
* b) Intravenous vancomycin is useful in treating post-operative endophthalmitis
* c) Rifampicin is only effective against tuberculosis
* d) Gentamicin is effective against Gram-positive coccus
* e) Penicillin is effect against Gram-positive coccus, Gram-negative bacilli and coccus
Answer a. T b. F c. F d. F e. F
19. Gram-negative rods that are known to cause ocular diseases include:
* a) Proteus vulgaris
* b) Serratia marcescans
* c) Pseudomonas aeruginosa
* d) Moraxella lacunata
* e) Haemophilus influenza
Answer a. T b. T c. T d. T e. T
* a) It is a virus specific molecule
* b) It acts by neutralizing exotoxin
* c) It enhances the histocompatibility antigen on cell surface and thereby activates the T cells
* d) It exerts its effect by integrating itself with the DNA of virus-infected cells
* e) It can inhibit cell division in normal tissue
Answer a. F b. F c. T d. F e. T
* a) endolymph is found in the tunnel of Corti
* b) The lowest tone that be heard is 300 Hz
* c) The perilymph has the same composition as the cerebrospinal fluid
* d) The longer fibers of the basilar membrane are found at the apex
* e) Linear acceleration is detected by maculae of the utricles
Answer a. F b. F c. T d. T e. T
22. The following are true about blood coagulation:
* a) Heparin inhibits blood coagulation through its interference with vitamin K metabolism in the liver
* b) Addition of vitamin K to freshly drawn blood delays clotting
* c) Thrombin converts fibrinogen to fibrin
* d) Platelets are essential for blood clot
* e) Vitamin K is responsible for the production of factors II, VII, IX and X
Answer a. F b. F c. T d. T e. T
23. With regard to the autonomic nervous system:
* a) The dorsal root ganglia is made up mainly of the cell bodies of the sympathetic nerves
* b) The preganglionic sympathetic fibers are usually longer than preganglionic parasympathetic fibers
* c) Acetylcholine is the neurotransmitter at the ganglia of both sympathetic and parasympathetic nervous system
* d) Botulin toxin blocks acetylcholine receptors
* e) Hemicholinium blocks the synthesis of acetylcholine
Answer a. T b. F c. T d. F e. T
* a) Is absent in the plasma of people without diabetes mellitus
* b) The levels of Hb A1C are a good index of glucose-induced arteriolar dilatation and consequent damage to renal function in diabetics
* c) Results from the combination of a HbA and a sugar
* d) When measured as HbA1c in plasma gives more accurate retrospective estimates of blood sugar levels than other glycosylated products
* e) Is increased in diabetic patient with concurrent sickle cell disease
Answer a. F b. T c. T d. F e. F
* a) Is a monosynaptic reflex with a response time of 1 msec
* b) Is enhanced by impulses from Golgi tendon organ
* c) Originates in the muscle spindle which sends off impulses in type Ia nerve fibers
* d) Is intensified by impulses in the gamma efferent fibers
* e) Is decreased in lesion of the motor cortex
Answer a. T b. F c. T d. T e. F
26. True statements about EOG include:
* a) It depends on a normal retinal pigment epithelium
* b) It can be easily produced in the anaesthetized patients
* c) The maximal dark response exceeds the light response in normal people
* d) It is given in an absolute value in microvolts
* e) In Best's disease, EOG is abnormal in the presence of normal ERG
Answer a. T b. F c. F d. F e. T
27. True statements about ERG include:
* a) It is abnormal in-patient with amblyopia
* b) It can be performed on anaesthetized patients
* c) It is affected by optic neuritis
* d) The a wave is produced by the photoreceptors
* e) Dark adaptation increase the amplitude of the a and b wave as well as the latency
Answer a. F b. T c. F d. T e. T
28. True statements about the aqueous humour:
* a) Has a higher lactic acid concentration than in the plasma
* b) The glucose levels is lower than that of the plasma levels
* c) The ascorbic acid concentration is twice that of the plasma
* d) It contains the same concentration of protein as in the plasma
* e) The rate of formation is about 2.5ul/minute
Answer a. T b. F c. F d. F e. T
29. With regard to the blood retina barrier:
* a) The outer blood retina is formed by the retinal pigment epithelium cells and their junctions
* b) The basement membrane of the retinal capillaries is a major component of the inner blood retina barrier
* c) The blood retina barrier is typically defective in the immediate perpapillary region
* d) The retinal vascular endothelial cells can actively transport fluid and anions from the extra cellular space of the retina into the circulation
* e) Inhalation of 10 % of carbon dioxide causes rapid breakdown of the inner blood retinal barrier
Answer a. T b. F c. T d. T e. T
* a) Hyperpolarisation occurs due to closure of the sodium channels
* b) Dark current only occurs in the presence of photoreceptors stimulation
* c) 11-cis-retinal molecules are converted to all-trans-retinal
* d) Transducin, a G protein converts GDP to GTP
* e) 10 photons are required to stimulate a single rod
Answer a. T b. F c. T d. T e. F
31. True statement about dark adaptation includes:
* a) There is a shift in peak spectral sensitivity from 555 nm to 505 nm with dark adaptation
* b) Rods are more sensitive than cone during dark adaptation
* c) Biphasic changes only occur in retina, which processes both rods and cones
* d) Its takes about 30 seconds in man
* e) It is delayed in-patient with vitamin A deficiency
Answer a. T b. T c. T d. F e. T
* a) Has a higher refractive index in the nucleus than the cortex
* b) Contains a higher potassium concentration than the aqueous
* c) Contains a higher concentration of sorbitol in diabetic patient than normal population
* d) Glucose is metabolised mainly by aerobic glycolysis
* e) Contains nucleated cells mainly on its posterior surface
Answer a. T b. T c. T d. F e. F
* a) Contributes to the refractive function of the eye
* b) Is partly formed from the goblet cells
* c) Is 100um thick?
* d) Its normal break-up time is 5 to 15 seconds
* e) Is decreased with topical atropine
Answer a. T b. T c. F d. F e. T
34. The intraocular pressure can fluctuate:
* a) Seasonally
* b) Diurnally
* c) With eye movements
* d) In optic neuritis
* e) With fluid intake
Answer a. T b. T c. T d. F e. T
35. The retinal-pigment epithelium cells are
* a) esterify and store excess retinol
* b) Transport retinol-binding protein from blood to subretinal space
* c) Are secured laterally to each other by tight junction
* d) Are independent units and do not communicate electrically or metabolically with each other
* e) Dehydrate the subretinal space and create forces binding themselves to neurosensory retina
Answer a. T b. T c. T d. F e. T
