As with amino acids and peptides, various classes of saponifiable lipids can often be separated by electrophoresis.

a. Could a mixture of phosphatidylcholine and phosphatidylserine be separated by electrophoresis at pH 7? Explain.

b. At what pH range (from pH 0-14) would it be possible to separate a mixture of phosphatidylcholine and phosphatidylethanolamine by electrophoresis? Explain.

Explain why biological membranes are said to be selectively permeable or semipermeable. Address how materials like amino acids, carbohydrates, ions and water can pass through the biological membrane. Be sure to talk about the similarities and differences between diffusion, facilitated diffusion, osmosis and active transport. (7 points)

Given that a pair of homologous genes are expressed in a bacterial and a vertebrate cell at the same rate of transcription (bp transcribed/second) and at the same rate of translation (amino acids translated/second), provide three reasons why the bacterial forms of the 9 might be expressed at a much faster rate after gene activation.

Which of the amino acids neurotransmitters would be responsible for producing an action potential and which would most likely be released to prevent an action potential from occurring? Can you think of a time when it might be helpful to have a neurotransmitter that, when it binds to the post-synaptic cell, it inhibits an action potential?

protein molecules are polypetide chains are made up of amino acids in their phisologically functoning or native state these chains fold in a unique manner such that the nonpolar groups of the amino acids are usually burired in the interior region of the proteins where there is little or no contact with water. when a protein denatures the chain unfolds so that these non polar groups are exposed to water. a useful estimate of the changes of the thermodynamic quantities as a result of denturation is to consider the transfer of hydrocarbon such as methane from an invert solvent to the aqueous enviroment:

a) CH₄ => CH₄ ​(g)

b) CH₄​=> CH₄ (aq)

if the values of delta H and delta G are approximately 2.0 kJ/ mol and -14.5 kj/mol respectively for (a) and -13.5 kJ / mol and 26.5 kJ/mol , respectively for b) calulate the values of delta H and delta G for the transfer of 1 mole of CH₄

​according to the equation

CH₄ =>CH₄ (aq)

comment on your results assume T = 298 k

protein molecules are polypetide chains are made up of amino acids in their phisologically functoning or native state these chains fold in a unique manner such that the nonpolar groups of the amino acids are usually burired in the interior region of the proteins where there is little or no contact with water. when a protein denatures the chain unfolds so that these non polar groups are exposed to water. a useful estimate of the changes of the thermodynamic quantities as a result of denturation is to consider the transfer of hydrocarbon such as methane from an invert solvent to the aqueous enviroment: a) CH4 => CH4 ​(g) b) CH4​=> CH4 (aq) if the values of delta H and delta G are approximately 2.0 kJ/ mol and -14.5 kj/mol respectively for (a) and -13.5 kJ / mol and 26.5 kJ/mol , respectively for b) calulate the values of delta H and delta G for the transfer of 1 mole of CH4 ​according to the equation CH4 =>CH4 (aq) comment on your results assume T = 298 k

Simon and Adrienne are healthy people who lived in a rural area with poor health services when they had their first child, Benjie. He had seizures in infancy, and as he grew into toddlerhood it became apparent that he was severely mentally retarded. He died at 26 months of age. Because he had never been diagnosed with a specific disorder, an autopsy was performed. His brain showed signs of great derangement, with nerve cells degenerating and missing. No diagnosis was made, and because no other relatives had been affected, a genetic problem was not suspected. The family physician assured the couple that the condition was not likely to repeat. The couple waited a few years, then had another child after moving to Chicago. When little Julie had the same symptoms as her brother, Simon and Adrienne took her to a major medical center. Urine and cerebrospinal fluid tests revealed large amounts of the chemical carnosine, which consists of two types of amino acids, alanine and histidine, joined together. Digestion should have broken the carnosine down into the individual amino acids, which are small enough to enter the bloodstream. When a medical geneticist learned of Julie's test results, she tested the urine of the parents. Each had half the normal activity for an enzyme called carnosinase. Julie has, and Benjie had, an inherited disorder, carnosinemia.

1. The mode of inheritance for carnosinemia in this family is __________ .

2. What is the biochemical evidence that indicates the mode of inheritance?

3. The probability that Simon and Adrienne can conceive a child who does not inherit carnosinemia is ____

4. The probability that they can conceive a child who is a carrier like they are is_____.

5. Devise a treatment for carnosinemia. 6. In one experiment on two children with carnosinemia, all sources of dietary protein with an alanine next to a histidine were eliminated from the diet. The children still excreted carnosine in the urine. What is an explanation for this finding?

In the human genetic disease sickle cell anemia, a single change in the genetic sequence of the hemoglobin-beta gene results in the amino acid valine being substituted for the amino acid glutamic acid in the beta chain of the hemoglobin protein. Which level(s) of the protein structure will be affected?

1. Describe how the unique reactions of GNG represent a pathway distinct from glycolysis based on the free change of the reaction catalyzed by the glycolysis enzyme, phosphofructokinase
2. Describe the functions of phosphoglucomutase and glucose 6-phosphatase enzymes in the pathway connecting glycogen breakdown to glucose export in liver cells.

3. Gluconeogenesis (GNG)

   Review coupled reactions (McKee page 120-121). It is useful and customary to express the number of GTP, UTP, or other nucleotides consumed or produced in a pathway as equivalent to ATP. A cellular reaction that exchanges the terminal phosphate between ADP and another nucleoside diphosphate is catalyzed by nucleoside diphosphate kinase (McKee page 347) One of the reactions of GNG consumes GTP. The task is to find the overall reaction that gives the equivalent change in ATP.