Ophthalmology

* a) Its nucleus is in the floor of the fourth ventricle

* b) Its fibres reach the surface of the brain in the cerebellopontine angle

* c) Transmits taste fibres for the anterior half of the tongue

* d) Gives the deep petrosal nerve as branch to the sphenopalatine ganglion

* e) Has a sensory component that supplies the outer ear

Answer a. T b. T c. T d. F 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

* 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) 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

* 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

* 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

* 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) 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

* 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

* 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) 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

* 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) 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

* 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

* 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

* 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

* 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

* 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

* 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) 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