8 - physiology new mcqs - part 2

11q. the parvocellular pathway from the lateral geniculate nucleus to the visual cortex carries signals for the detection of ?

 

1. movement , depth and flicker
2. color vision , shape and fine details
3. temporal frequency
4. luminance contrast

 

answer: b . color vision , shape and fine details . the fibers from the 1 and 2 layers of LGB reach the visual cortex through the magnocellular pathway and the fibers from the 3,4,5,6 layers reach the visual cortex through the parvocellular pathway .

 

12q. the parvocellular pathway from lateral geniculate nucleus to visual cortex is most sensitive for the stimulus of ?

 

1. color contrast
2. luminance contrast
3. temporal frequency
4. saccadic eye movements

 

answer: a . color contrast .

 

13q. relative color and luminosity of photoreceptive input under changing light conditions are regulated and maintained by ?

 

1. muller cells
2. amacrine cells
3. ganglion cells
4. retinal astrocytes

 

answer: b . amacrine cells .

 

14q. during the dark phase of the visual cycle , which form of vitamin A combines with opsin to make rhodopsin ? ( retinaldehyde = retinal )

 

1. all trans retinaldehyde
2. all trans retinol
3. 11-cis-retinaldehyde
4. 11-cis-retinol

 

answer: c . in the dark phase 11-cis-retinal combines with opsin and in the light phase 11-trans-retinal combines with opsin to form rhodopsin .

( mnemonic : in the dark I thought she was my SISTER and when the light came she was a TRANSEXUAL )

 

15q. visible range of electromagnetic spectrum of human eye is ?

 

1. 370-740 nm
2. 740-1140 nm
3. 200-340 nm
4. 200-370nm
5. 370-770nm

 

answer: a . 350-600 is the actual answer .

 

16q. nucleus of basal ganglia ?

 

1. dentate
2. thalamus
3. caudate
4. red nucleus

 

answer: c . caudate .  basal ganglia consists of CAUDATE NUCLEUS, PUTAMEN, GLOBUS PALLIDUS, SUBTHALAMIC NUCLEUS and SUBSTANTIA NIGRA .

 

17q. the efferent fiber bundle of the substantia nigra transmits dopamine to one of the following areas ?

 

1. thalamus
2. corpus striatum
3. tegmentum of pons
4. tectum of midbrain

 

answer: b . corpus striatum .

 

18q. which of the following acts as a major neurotransmitter in substantia nigra ?

 

1. dopamine
2. noradrenaline
3. acetyl choline
4. serotonin

 

answer: a . dopamine .

 

19q. functions of the basal ganglia include ?

 

1. gross motor
2. skilled movements
3. emotions
4. maintenance of equilibrium
5. cordiantion of movements

 

answer: b . skilled movements . functions of the basal ganglia include planning and programming of movements, subconscious execution of learned pattern of movement and cognitive control of sequence of motor pattern .

 

20q. which of the following clearly states the role of basal ganglia in motor function?

 

1. planning
2. skilled function
3. coordinate function
4. balance
5. coarse movements

 

answer: a . planning .