In addition to the predominant adult hemoglobin, HbA, which contains two $\alpha$-globin chains and two S-globin chains $\left(\alpha_{2} \beta_{2}\right),$ there is a minor hemoglobin, HbA, composed of two $\alpha$ and two $\delta$ chains $\left(\alpha_{2} \delta_{2}\right).$ The $\beta-$ and $\delta-$globin genes are arranged in tandem and are highly homologous. Draw the chromosomes that would result from an event of unequal crossing-over between the $\beta$ and $\delta$ genes.

In 1952, an article in the British Medical Journal reported interesting differences in the behavior of blood plasma obtained from several individuals who suffered from X-linked recessive hemophilia. When mixed together, the cell-free blood plasma from certain combinations of individuals could form clots in the test tube. For example, the following table shows whether (+) or not (-) clots could form in various combinations of plasma from four individuals with hemophilia:

$$\begin{matrix} \text{1 and 1} & \text{$-$} & \text{ } & \text{2 and 3} & \text{$+$}\\ \text{1 and 2} & \text{$-$} & \text{ } & \text{2 and 4} & \text{$+$}\\ \text{1 and 3} & \text{$+$} & \text{ } & \text{3 and 3} & \text{$-$}\\ \text{1 and 4} & \text{$+$} & \text{ } & \text{3 and 4} & \text{$-$}\\ \text{2 and 2} & \text{$-$} & \text{ } & \text{4 and 4} & \text{$-$}\\ \end{matrix}$$

What do these data tell you about the inheritance of hemophilia in these individuals? Do these data allow you to exclude any models for the biochemical pathway governing blood clotting?

Find an example of a matched pairs study on the web. The Journal of the American Medical Association, Science Magazine, the Canadian Medical Association Journal, the Journal of Statistics Education, or perhaps the Journal of Quantitative Analysis in Sports are possible sources. To help locate an article, look through the abstracts of articles. Once you find a suitable article, read it, and then briefly describe the study (including why it is a matched pairs study) and its conclusions. If P-values, means, standard deviations, and so on are reported, be sure to include them in your summary. Also, be sure to give the reference (either the web link or the journal, issue, year, title of the paper, authors, and page numbers).

What happens when velocity and acceleration are not in the same direction? What kind of motion occurs?

The intermediates A, B, C, D, E, and F all occur in the same biochemical pathway. G is the product of the pathway, and mutants 1 through 7 are all $G^{-},$ meaning that they cannot produce substance G. The following table shows which intermediates will promote growth in each of the mutants. Arrange the intermediates in order of their occurrence in the pathway, and indicate the step in the pathway at which each mutant strain is blocked. A + in the table indicates that the strain will grow if given that substance, an O means lack of growth.

$$\text{Supplements}\\ \begin{matrix} \hline \text{Mutant} & \text{A} & \text{B} & \text{C} & \text{D} & \text{E} & \text{F} & \text{G}\\ \hline \text{1} & \text{$+$} & \text{$+$} & \text{$+$} & \text{$+$} & \text{$+$} & \text{$\mathrm{O}$} & \text{$+$}\\ \text{2} & \text{$\mathrm{O}$} & \text{$\mathrm{O}$} & \text{$\mathrm{O}$} & \text{$\mathrm{O}$} & \text{$\mathrm{O}$} & \text{$\mathrm{O}$} & \text{$+$}\\ \text{3} & \text{$\mathrm{O}$} & \text{$+$} & \text{$+$} & \text{$\mathrm{O}$} & \text{$+$} & \text{$\mathrm{O}$} & \text{$+$}\\ \text{4} & \text{$\mathrm{O}$} & \text{$+$} & \text{$\mathrm{O}$} & \text{$\mathrm{O}$} & \text{$+$} & \text{$\mathrm{O}$} & \text{$+$}\\ \text{5} & \text{$+$} & \text{$+$} & \text{$+$} & \text{$\mathrm{O}$} & \text{$+$} & \text{$\mathrm{O}$} & \text{$+$}\\ \text{6} & \text{$+$} & \text{$+$} & \text{$+$} & \text{$+$} & \text{$+$} & \text{$+$} & \text{$+$}\\ \text{7} & \text{$\mathrm{O}$} & \text{$\mathrm{O}$} & \text{$\mathrm{O}$} & \text{$\mathrm{O}$} & \text{$+$} & \text{$\mathrm{O}$} & \text{$+$}\\ \end{matrix}$$

The pathway for arginine biosynthesis in Neurospora crassa involves several enzymes that produce a series of intermediates.

$$\quad A R G-E \quad A R G-F \quad A R G-G \quad A R G-H$$

$N$-acetylornithine $\rightarrow$ ornithine $\rightarrow$ citrulline $\rightarrow$ argininosuccinate $\rightarrow$ arginine

If you did a cross between $A R G-E^{-}$and $A R G-H^{-}$ Neurospora strains, what would be the distribution of $\mathrm{Arg}^{+}$and $\mathrm{Arg}^{-}$spores within parental ditype and nonparental ditype asci? Give the spore types in the order in which they would appear in the ascus.

Then, for each of them, answer what nutrients could you supply in the media to get spore growth?

The pathway for arginine biosynthesis in Neurospora crassa involves several enzymes that produce a series of intermediates.

$$\begin{matrix} \text{ } & \text{$\arg E$} & \text{ } & \text{$\arg F$} & \text{ } & \text{$\arg G$} & \text{ } & \text{$\arg H$} & \text{ }\\ \text{N-acetylornithine} & \text{$ \rightarrow$} & \text{ornithine} & \text{$ \rightarrow$} & \text{citrulline} & \text{$ \rightarrow$} & \text{argininosuccinate} & \text{$ \rightarrow$} & \text{arginine}\\ \end{matrix}$$

a. If you did a cross between argE$^-$ and argH$^-$ Neurospora strains, what would be the distribution of Arg$^+$ and Arg$^-$ spores within parental ditype and nonparental ditype asci? Give the spore types in the order in which they would appear in the ascus. b. For each of the spores in your answer to part a, what nutrients could you supply in the media to get spore growth?

What is differentiation?

Evaluate each expression. 8 - 3 - 4

How are environmental issues in Central Asia being addressed?

A gas has pressure

$$8.2 \times 10 ^ { 6 } \mathrm { Pa }$$

and volume

$$2.3 \times 10 ^ { - 3 } \mathrm { m } ^ { 3 }$$

. The pressure is reduced to

$$4.5 \times 10 ^ { 6 } \mathrm { Pa }$$

at constant temperature. Calculate the new volume of the gas.

Explain why a person requires only small amounts of vitamins in his or her diet.

Find $\int \frac{1}{1+e^{-x}} d x.$ [Hint: Write $e^{-x}$ as $\frac{1}{e^{x}},$ and simplify the complex fraction before making an appropriate substitution.]

Write a sentence explaining its significance to electing leaders. precincts