ShmoopTube

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And here's your shmoop du jour brought to you by the optic

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nerve the reason your big brother gets annoyed just looking at you... Alright [Little brother jumps on big brothers bed]

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here's the question the place in the back of the eye where the optic nerve

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leads the retina and has no rods or cones is called what and here are your potential

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answers....Okay so the question is looking for a place in the

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back of the eye with no rods and no cone let's keep that in mind as we look at our answers [A metal rod and an ice cream cone appear]

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is this place where the optic nerve leaves the retina A; the fovea well the

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fovea is a small pit in the center of the eye composed of closely packed cones [A construction man with two orange cones in the fovea]

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it's responsible for sharp clear focused vision wait did we hear cones sorry

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phobia this zone is a no cones allowed.. not to mention the whole back of the eye [Person crosses out 'back of the eye' and 'no cones']

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thing so we can lose A...Everybody knows the back of the eyes where all the cool

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kids sit...We meant bus what about C? Broca's area well that's a region of the [School kid sitting at the back of the bus]

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frontal lobe but yeah okay already wrong frontal lobe is in your brain, not in [Hand points to man's brain and eye]

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your eye but in case you're really curious its function is primarily linked

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to speech production entirely unrelated to the discussion at hand but

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responsible for our ability to have that discussion at all...So thanks Broca so

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wrong but so right...Could it be D..well the lateral geniculate nucleus is a [Lateral geniculate nucleus shown in the brain]

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structure in the thalamus that acts as the primary relay center for the optic

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nerve in the thalamus.. not the back of the eye so D is out of the running and

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E the optic chiasm is the part of the brain where the two optic nerves [Optic nerves shown crossing over in a diagram]

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partially cross, again part of the brain not back of the eye... the brains really

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making itself a pain today.. So we can cross out E as well so that means our answer

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must be B, the blind spot which describes the part of the retinal wall [Car stutters down a road before parking]

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within the eye so it doesn't have any cones or rods in order to make room for

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the optic nerve to exit the eyeball this prohibits any light waves from being

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transduced at that spot therefore creating a blind spot so B as in blind

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spot is correct...A good thing we weren't blinding

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the answer, right? [Man wearing an eyepatch]

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