Describe why a protein that binds to a specific sequence of double-stranded DNA is unlikely to bind to the same sequence if the DNA is single-stranded.

Boundary-layer analysis for fluid flow over a flat plate predicts the following relationships between the local Sherwood $\left(\mathrm{Sh}_{x}\right)$. Reynolds (Re), and Schmidt (Sc) numbers:

$$\text { for laminar flow, } \operatorname{Sh}_{x}=\frac{k_{c} x}{D_{A B}}=0.332 \mathrm{Re}_{x}^{1 / 2} \mathrm{Sc}^{1 / 3}$$

$$\text { for turbulent flow, } \mathrm{Sh}_{x}=\frac{k_{c} x}{D_{A B}}=0.0292 \mathrm{Re}_{x}^{-4 / 5} \mathrm{Sc}^{1 / 3}$$

with the transition beginning at $\operatorname{Re}_{x}=2.0 \times 10^{5}$. Determine what percentage of the mass transfer occurs within the laminar zone of the flow over the flat plate if the Reynolds number at the end of the plate is $\operatorname{Re}_{L}=3.0 \times 10^{6}$.

Use your calculator to find the approximate value of each expression, correct to five decimal places. $\ln 9.98$

The table gives the US population from 1790 to 1860.

$$\begin{array}{|c|c|c|c|} \hline \text { Year } & {\text { Population }} & {\text { Year }} & {\text { Population }} \\ \hline 1790 & {3,929,000} & {1830} & {12,861,000} \\ {1800} & {5,308,000} & {1840} & {17,063,000} \\ {1810} & {7,240,000} & {1850} & {23,192,000} \\ {1820} & {9,639,000} & {1860} & {31,443,000} \\ \hline \end{array}$$

Use a graphing calculator or computer to fit an exponential function to the data. Graph the data points and the

Arrange the following five compounds in order of decreasing rate of bromination: benzene, toluene, o-xylene, m-xylene, 1,3,5- trimethylbenzene (the relative rates are 2 $\times$ $10^{7}, 5 \times 10^{4}, 5 \times 10^{2}$, 60, and 1).

Explain the meaning of each of the following statements. $\lim _{x \rightarrow-\infty} f(x)=L$

A certain compound A, when treated with N-bromosuccinimide and benzoyl peroxide under photochemical conditions in refluxing carbon tetrachloride, gave 3, 4, 5-tribromobenzyl bromide in excellent yield. Deduce the structure of compound A.

What are the functions of the Sec and Tat systems and why are they necessary? How do these systems know which proteins to act upon?

What proteins are involved in refolding misfolded proteins? What other functions do they have?

Why is genetic code considered degenerate or redundant? Describe wobble hypothesis of tRNA recognition.

Why is the genetic code a degenerate code? What is wobble and how does it accommodate fidelity in the genetic code?

How does the archaeal RNA polymerase differ from that in Bacteria? How does the initiation of transcription in the two domains differ? Why do eukaryotic mRNAs have to be "processed" whereas most prokaryotic RNAs do not?

Starting with the Fick's rate equation for the diffusion of A through a binary mixture of components A and B, given by

$$\mathbf{N}_{A}=-c D_{A B} \nabla y_{A}+y_{A}\left(\mathbf{N}_{A}+\mathbf{N}_{B}\right)$$

show that

$$\mathbf{n}_{A}=-D_{A B} \nabla \rho_{A}+w_{A}\left(\mathbf{n}_{A}+\mathbf{n}_{B}\right)$$

and state all assumptions needed to arrive at this result.

How does RNA polymerase know where to begin transcription? How does it know where to end?