48 lines
1.9 KiB
TeX
48 lines
1.9 KiB
TeX
\documentclass[a4paper,12pt,pdftex]{exam}
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\newcommand{\ptitle}{Photoreceptor activity}
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\input{../header.tex}
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\firstpagefooter{Supervisor: Jan Grewe}{phone: 29 74588}%
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{email: jan.grewe@uni-tuebingen.de}
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\begin{document}
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\input{../instructions.tex}
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%%%%%%%%%%%%%% Questions %%%%%%%%%%%%%%%%%%%%%%%%%
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\section*{Analysis of insect photoreceptor data.}
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In this project you will analyse data from intracellular recordings of
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a fly R\.1--6 photoreceptor. The membrane potential of the
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photoreceptor was recorded while the cell was stimulated with a
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light stimulus.
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\begin{questions}
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\question{} The accompanying dataset (photoreceptor\_data.zip)
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contains seven mat files. Each of these holds the data from one
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stimulus intensity. In each file are three variables. (i)
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\textit{voltage} a matrix with the recorded membrane potential from
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10 consecutive trials, (ii) \textit{time} a matrix with the
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time-axis for each trial, and (iii) \textit{trace\_meta} a structure
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that stores several metadata. This is the place where you find the
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\emph{amplitude}, that is the voltage that drives the light
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stimulus, i.e. the light-intensity.
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\begin{parts}
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\part{} Create a plot of the raw data. Plot the average response as
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a function of time. This plot should also show the
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across-trial variability.\\[0.5ex]
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\part{} You will notice that the responses have three main parts, a
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pre-stimulus phase, the phase in which the light was on, and
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finally a post-stimulus phase. Create an characteristic curve that
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plots the response strength as a function of the stimulus
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intensity for the ``onset'' and the ``steady state''
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phases.\\[0.5ex]
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\part{} The light switches on at time zero. Estimate the delay between stimulus.\\[0.5ex]
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\part{} You may also decide to analyze the post-stimulus response in some
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more detail.
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\end{parts}
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\end{questions}
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\end{document}
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