Question: $1$E Why should your picture and your mathematical representation be consistent with one another? Question $1$A: From the choices shown below, choose which of these two general depictions of gene structure on the chromosome you will modify to fit this scenario.

Option A

Option B

I choose Option

Given the information in the question, provide at least three reasons based on what is represented in these diagrams for your choice.

Question $1$B: Below are two of the equations we generated in class to represent gene regulation.

Option A: $\backslash (\backslash$quad$(1-$R$)(1+$A$)^\{*\}$ S$^\{*\}$ P$=$T $\backslash )$

Option B: $\backslash (\backslash$quad$(1-\backslash$mathrm$\{$R$\})(1+\backslash$mathrm$\{$A$\})*$ T F $1*$ T F $2*$ T F $3*$ T F $4*$ T F $5*$ P $*$ C$=$T $\backslash )$

Where $\backslash (\backslash$mathrm$\{$R$\}=\backslash )$ Repressor, $\backslash (\backslash$mathrm$\{$A$\}=\backslash )$ Activator, $\backslash (\backslash$mathrm$\{$TF$\}=\backslash )$ Transcription Factor, $\backslash (\backslash$mathrm$\{$S$\}=\backslash )$ Sigma, $\backslash (\backslash$mathrm$\{$P$\}=\backslash$mathrm$\{$RNA$\}\backslash )$ polymerase, $\backslash (\backslash$mathrm$\{$C$\}=\backslash$mathrm$\{$chromatin$\}\backslash )$

Which of the two equations would you choose to modify to represent this situation?

I choose Option

Given the information in the question, provide at least two reasons based on what is represented in these mathematical equations for your choice.

Question $1$C: Modify your chosen diagram of the chromosome structure AND your chosen mathematical equation to explain how ANTE and POST are controlling the expression of ABD. You will need to show proteins binding in your diagrams. Be sure to include all proteins necessary for gene expression.

i$.$ Paste picture of modified diagram here $($Include a key!$)$:

ii$.$ Modified mathematical equation $($Include a key!$)$:

Question $1$D: Explain how your modifications to BOTH the picture and the mathematical representation provide a model for gene regulation of gene ABD. Include in your explanation what you kept the same and what you changed and why. Gene Regulation

This question addresses how body position is set up in a developing embryo and how proteins involved in gene regulation are involved. While the creature is not real and the biology has been drastically simplified, the principles are the same as those that actually occur. Figure $1$C shows the adult ant$-$like eukaryotic organism. This organism has three body parts $($tail$,$ abdomen, head$)$ which are set up by the distribution of two proteins after fertilization. The egg contains two proteins $($ANTE and POST$)$ which are evenly distributed. Once the egg is fertilized, these proteins are redistributed into a gradient such that ANTE is more heavily concentrated at what will become the anterior $($head$)$ of the organism and POST is more heavily concentrated at what will become the posterior $($tail$)$ of the organism $($Figure $1$Ai$,1$Aii, $1$Aiii$).$ ANTE and POST are proteins that regulate gene expression of three genes: TL$,$ ABD, HD $($Figure $1$B$,$ Table $1).$ The proteins produced by these genes will then, in conjunction with proteins that determine back and stomach position, regulate other genes to produce the structures associated with each body segment. For this question, we are going to focus on how gene regulation by ANTE and POST produces the gene expression of the ABD protein that is shown in Figure $1$B$.$

Figure $1.$ Control of body plan by gene regulation

$1$Ai$.$ Levels of ANTE protein expression in the embryo after fertilization

$1$Aii. Levels of POST protein expression in the embryo after fertilization

$1$Aiii. Levels of ANTE and POST protein expression in the embryo after fertilization

$1$B$.$ TAIL, ABD and HD protein expression

Table $1$: Levels of ANTE and POST protein that are associated with gene expression of TAIL, ABD, HEAD genes

$1$C$.$ The Ant$-$like Organism