For a sex-linked gene at which there are two alleles, A1 and A2, in a population and for which the frequency of A1 is 0.9 in females and 0.3 in males, what will be the frequency of the A1 allele in the male offspring (sons) after one generation of random mating?

3) You have four tubes containing the same DNA at the same concentration in each tube (pH 7.5) but under different environmental conditions (listed below). The TM for this DNA molecule is 78°C at physiological salt conditions (~100 mM NaCl): a. DNA in an aqueous solution that has been digested completely to nucleotides with DNAse I enzyme. b. DNA in an aqueous solution containing no salt and has been heated to 78°C. c. DNA in an aqueous solution containing physiological concentrations of salt and heated to 78°C. d. DNA in an aqueous solution containing physiological concentrations of salt and is heated only to 37oC. Match the samples above with their corresponding OD260 readings. Next, explain your reasoning for each of the matches you made. (For example, “The DNA in sample (a) gives the highest OD reading because…”). • OD260 = 0.620 • OD260 = 0.960 • OD260 = 0.475 • OD260 = 0.271

1. Prior to the AIDS epidemic, what type of population growth was occurring in sub-Saharan Africa?
2. Approximately how many people in sub-Saharan Africa are infected with HIV? How many died in the last year?
3. What sorts of general changes will this dramatic number of deaths cause to the population structure of these sub-Saharan African countries?
4. What will happen to the age structure of the population? What about birthrates?
5. Although there have been many efforts to help educate infected patients in how to slow or stop the spread of HIV, these efforts have not been successful in some parts of Africa. Why is this?

Using the Library link or any biology websites to find an enzyme that is related to either a disease or a condition (human, animal or plant) and place a summarizing paragraph on the thread below.

Consider including:

1. 1 point description of disease or condition

2. 1 point for a brief description of the symptoms of the disease or expression in plants

3. 1 point for description of the protein involved

4. 1 point for anecdote(story) related to the disease or interesting information about the condition.

5. 1 point for relating disease to specific cell organelle

Explain how the cell reproduction rate and differentiation are kept within the normal range to avoid the formation of neoplasms. (in regards to leukemia cancer)

I am trying to purify DNA polymerase from cells DNA polymerase is a large soluble posivitely charged protein for each purification step below select which fractions you will keep in order to end up with pure DNA polymersase :

1. Cell fractioniation by centrifiguation:

a) Keep Nuclear Pellet

b) Keep mitochondrial Pellet

c) Keep microsomal supernatant

d) Keep microsomal Pellet

2) Salt fractionation with low salt concentration (low salt):

a) Keep precipitate

b) Keep supernatant

3) Gel Filtration

a) Keep later fractions

b) Keep middle fractions

c) Keep earlier fractions

4) Cation exchanger:

a) Keep middle fractions

b) Keep later fractions
c) Keep earlier fractions

5) DNA containing affinity column:

a) Later fractions

b) Earlier fractions

You are a judge in a civil trial where a young man is attempting to prove that he is the illegitimate child of a very wealthy man who has recently died. He wishes to be included in the distribution of the wealth. After considering all the testimony about how this person was conceived, the key evidence seems to come down to two main facts. The wealthy man and the mother of the young man are both deaf but the young man is not. Therefore the lawyer of the family suggests that the wealthy man is not the father. The mother, wealthy man, and young man all have O, MM, Rh blood type at the phenotypic level but a genotyping screen indicates that the wealthy man is actually I^AI^A hh blood type. How do you interpret the evidence presented and how does it influence your decision in this case?

Some scientists believe that fructose is particularly bad for human health because it promote fat synthesis, contributing to development of type II diabetes and fatty liver disease. You are a scientist working for a lab attempting to develop a drug to help with such diseases called fructono. The idea is that fructono could be added to the diet to reduce fructose absorption; even though fructono would be absorbed, it would not be metabolized, and would be excreted by the kidney. The hypothesis is that fructono binds to the fructose transporter, competitively displacing fructose. This cannot be easily studied in humans, so you are investigating this hypothesis with a mouse small intestine, which is known to transport fructose using a transporter that is quite similar in amino acid sequence and structure to the human protein. For your research, you set up a perfused intestine prep. You cut out about 1 cm of small intestine, and put it in a dish containing saline. You insert a tube into the intestinal section, and use a pump to push any fluid you want through the lumen of the intestine. You have radio-labeled fructono, so you can measure its appearance in the saline outside the intestine. How can you measure the rate of transport of fructono? 1 pt Describe experiments that would test whether the absorption of fructono is protein-mediated vs. passive (just leaking through cracks, or diffusing through membranes). What results will you get if the transport is protein-mediated vs. passive? 2 pts. Describe experiments that would test whether the absorption of fructono is active, and the predicted results if transport is active or not. 2 pts. Describe experiments that will test whether the active transport of fructono requires luminal Na+, and the predicted result if transport is Na+-dependent or not. 1 pt. Describe experiments that will test whether fructono can reduce the transport of fructose in a dose-dependent manner. 2 pts What side-effects might fructono have? 2 pts

i) Discuss the importin-alpha nuclear import cycle, mechanistically accounting for the key steps of nuclear transport. (Essay style include appropriate diagrams)

ii) Quantitative reasoning, 10 marks: During DNA replication, the genome is duplicated as chromatin. How fast does nuclear transport of histones have to take place in terms of molecules/pore/second in order to support S-phase in human cells? Assume the genome is 6 x 109 bp, a nucleosome spans 200 bp and that 75% of the genome is replicated in the first 3 hr of S-phase. Nuclei contain 2000 nuclear pore complexes. (show work)

Which of the following are exocrine functions of the pancreas?

1) synthesis of hormone sensitive lipase

2) Secretion of insulin from beta islet cells

3) Synthesis of alkaline lipase

4) Synthesis of phospholipase A2

5) Synthesis of phospholipase D

6) Synthesis of trypsinogen

7) Synthesis and Release of salivary amylase

8) Synthesis and release of lingual acid lipase

Discuss the different levels of protein folding, giving example of particular folds. Discuss the difference between motifs and domains in folded proteins. Briefly discuss the difference between globular and fibrous protein structures.

Nondisjunction at meiosis II produces higher frequency of aneuploid gametes compared to meiosis I nondisjunction.

True or False?

Explain

1. What is the role of hemoglobin in CO₂ transport?
2. What is the role of bisphosphoglycerate (BPG) in hemoglobin’s oxygen affinity?
3. Describe the process of high-altitude adaptation
4. Fetal hemoglobin has low BPG affinity. What does this mean? Why is this relevant?

How many different explanations can you think of for the observation that the rate of mutation varies across the genome? How would you weigh up evidence for these different ideas to decide which ones have the most explanatory power?