annotate test.tex @ 0:0d795f02a8bb tip

initial committ. what was I thinking?
author Robert McIntyre <rlm@mit.edu>
date Mon, 27 Sep 2010 16:57:26 -0400
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rlm@0 1 Photoreceptors in the retina (such as cones) have special channels that are open to Na+ in the dark. When light hits photoreceptors, these special channels close. What can you conclude from this?
rlm@0 2 a) Photoreceptors depolarize to light.
rlm@0 3 b) Photoreceptors hyperpolarize to light.
rlm@0 4 c) Photoreceptor voltage does not change in the presence of light.
rlm@0 5 d) None of the above
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rlm@0 8 What happens in a photoreceptor cell (a rod, for example) in response to a light stimulus?
rlm@0 9 a) rod membrane depolarizes because Na+ channels open as a result of a decrease in second messenger cGMP
rlm@0 10 b) rod membrane hyperpolarizes because K+ channels open as a result of a decrease in second messenger cGMP
rlm@0 11 c) rod membrane hyperpolarizes because Na+ channels close as a result of a decrease in second messenger cGMP
rlm@0 12 d) rod membrane depolarize because K+ channels close as a result of a increase in second messenger cGMP
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rlm@0 15 A difference between rods and cones is:
rlm@0 16 a) Rods hyperpolarize to light, while cones depolarize to light
rlm@0 17 b) Rods are much larger than Cones, and more numerous.
rlm@0 18 c) Cones and rods use different types of opsins
rlm@0 19 d) The total volume of all Cones is smaller than that of Rods
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rlm@0 26 To approximate an ideal OpAmp, all OpAmps should:
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rlm@0 28 a) have almost infinite positive open loop gain
rlm@0 29 b) have almost infinite negative open loop gain
rlm@0 30 c) have almost infinite positive output drift
rlm@0 31 d) have almost infinite negative output drift
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rlm@0 37 Normal OpAmps all approximate an ideal OpAmp. An Ideal OpAmp:
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rlm@0 39 I Has infinite positive open loop gain
rlm@0 40 II Has zero open loop gain
rlm@0 41 III Is an IC
rlm@0 42 IV Has zero output drift
rlm@0 43 V Has output drift of -1
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rlm@0 46 a) I,III,V
rlm@0 47 b) II,III,V
rlm@0 48 c) II,V
rlm@0 49 d) I,IV
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rlm@0 54 A difference between the 741 OpAmp and the K2-W OpAmp is:
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rlm@0 56 a) the 741 has a large negative open loop gain while the K2-W has a large positive open loop gain
rlm@0 57 b) the 741 is an IC while the K2-W is not
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rlm@0 64 I