16. which is not synthesised in postganglionic sympathetic neurons a. L-dopa b. DA c. NA d. A e. ACh

Transcription

1 NERVOUS SYSTEM 1. Visual pathways a. Have P cells that are associated with colour b. Utilize the primary colours, red, yellow and blue c. Have simple cells which respond to all light stimuli d. Pass through the medial geniculate body e. Have a temporal path for motion 2. parasympathetic stimulation causes a. sweat secretion b. salivary secretion c. inhibition of peristalsis d. increase in HR e. vasoconstriction of abdominal viscera 3. A sense organ for pain is a. Merkel s disc b. Kranse end bulb c. Naked nerve endings d. Meissner s corpuscle e. Encapsulated endings 4. Pain transmission a. Is by peripheral B fibres b. Involves cholinergic transmission c. Is produced by over-stimulation of other receptor types d. Can be gated by presynaptic inhibition e. Is via fast C pain fibres 5. Co-transmitters released with NA include a. VIP and DA b. ATP and neuropeptide Y c. DA and neuropeptide Y d. Tyrosine and ATP e. ACh and VIP 6. The size of the action potential is decreased by a. Decreasing intracellular Ca b. Increasing external Na c. Decreasing the external Na d. Decreasing the internal K e. Increasing the internal K

2 7. all of the following ascending sensory pathways are located in the dorsal column except a. pain b. touch c. pressure d. vibration e. proprioception 8. concerning the visual pathway a. macular sparing occurs due to the arrangement of fibres in the optic tract b. Brodmann s area is located in the temporal lobe c. The optic tract ends in the medial geniculate body d. The optic disc lies 3mm medial to and slightly above the posterior pole of the globe e. a pituitary tumour often causes a homonymous hemianopia 9. within the sympathetic nervous system a. sweat glands are supplied by β2 receptors b. activation promotes gluconeogenesis c. bronchial glandular secretion is inhibited by β2 receptor stimulation d. at the post ganglionic neuron, DA is responsible for the slow excitatory post synaptic potential e. the preganglionic neurons leave the spinal cord in the ventral roots of the thoracolumbar spine 10. In the visual pathway a. Axons of the ganglion cells pass in the optic nerve and optic tract and end in the medial geniculate body of the hypothalamus b. Fibres of each temporal hemi-retina decussate in the optic chiasm c. The primary visual receiving area is Brodmann s area 17 d. The fovea contains no cones e. 80% of input to the geniculate nucleus comes from the retina, the other input is from brain regions involved in feedback regulation 11. Regarding reflexes a. The reaction time for knee jerk is 0.1s b. Jendrassik s manoeuvre enhances the knee jerk reflex c. Spindles are located in muscle tendons d. Afferent neurons carry the impulse to the muscle e. Muscle spindle fibres are innervated by Ib type nerve

3 12. Which of the following is false a. Unilateral transaction of the left optic tract causes a right sided homonymous hemianopia b. The fovea contains only cones c. Dark adaption is maximal at around 20 minutes d. Optic nerve fibres from the upper retinal quadrants terminate in the medial half of the lateral geniculate body e. Na channels in rods and cones are open in response to light 13. Which is false a. The alpha rhythm is the dominant rhythm seen on EEG of adults b. Corticospinal and corticobulbar system is the primary pathway for the initiation of skilled voluntary movement c. Basal ganglion is composed of the putamen, globus pallidus and substantia nigra d. Flocculonodular lobe is concerned with equilibrium e. Cold receptors respond from degrees Celsius 14. Characteristics of the brain, CSF and cerebral circulation include a. CSF volume of 150mL at a lumbar pressure of mm CSF b. CSF/plasma protein ratio of 1, glucose of 0.6 c. Weight of 1.4 kg suspended in CSF from the dura mater by arachnoid trabeculae d. Susceptibility to convulsions at normal BSLs in diabetics e. Oxygen consumption of 25mL/min ie 10% total body consumption 15. Regarding the ANS a. Does not have a reflex arc like somatic nervous system b. Has DA as the main neurotransmitter c. Hs cholinergic division which increases activity of intestinal musculature and increases gastric secretion d. Neurotransmitter NA is metabolized by pseudocholinesterase e. Is not involved in visceral sensation 16. which is not synthesised in postganglionic sympathetic neurons a. L-dopa b. DA c. NA d. A e. ACh

4 17. In the ANS β agonism results in a. Constriction of the renal vasculature b. Decreased velocity of conduction in the AV node c. Decreased velocity of conduction in the His/Pukinje system d. Decreased ventricular contractility e. Increased insulin and glucagons secetion 18. The reticular activating system a. Has depressed conduction during anaesthesia b. Is located in the pons c. Is a simple collection of parallel nerve fibres d. Has no input from cranial nerves e. Is electrically isolated from the cortex 19. the most sensitive part of the eye is the a. optic disc b. fovea centralis c. area with maximal rods 20. regarding CSF a. composition is essentially the same as brain ECF b. CSF production ~ 150mL/d c. Higher concentration of K with respect to plasma d. Higher concentration of protein 21. which penetrates the CSF fastest a. H 2 O, CO 2, O 2 b. CO 2, O 2, N 2 O 22. anterolateral dissection of the spinal cord is associated with a. ipsilateral loss of pain b. ipsilateral loss of temperature c. ipsilateral hyperreflexia d. contralateral vibration loss e. none of the above 23. The sensation for cold a. Is relayed by the thalamus b. Is transmitted by the dorsal columns c. Is an incrossed sensory modality d. Is mediated by substance P fibres e. Is mediated by A α fibres

5 ANSWERS 1. A 2. B 3. C 4. D 5. B 6. C 7. A 8. D 9. E 10. C 11. B 12. E 13. C 14. D 15. C 16. D 17. E 18. A 19. B 20. A 21. A 22. E 23. A