Which do you think would result in an immediate response (within seconds or minutes) and which would take time (several minutes or hours to work?

(1-6) alter effective activity (7-10) changes enzyme activity

1. extracellular signal         

2. transcription factors

3.mRNA degradation

4. mRNA translation on ribosome

5. protein degradation

6. enzyme in subcellular organelle

7. enzyme binds to substrate

8. enzyme binds ligand (allosteric effector)

9 enzyme undergoes phosphorylation/dephosphorylation

10. enzyme combines with regulatory proteins

In order to study the activity of enzyme X, cells were treated with either glucagon, dibutyryl cAMP, glucagon plus H-8, or glucagon with D-2 at does to achieve a maximal effect. The activity and concentration of enzyme X were then assayed in dilute cell-free extracts. Dibutyryl cAMP is an analog of cAMP that diffuses across cell membranes more easily than does cAMP itself. H-8 is a selective inhibitor of protein kinase A. D-2 is a selective inhibitor of CREB. The results are shown in the following table.

It can be inferred from these results that glucagon most likely acts to _____________ and the changes or part of the changes in activity of enzyme X are most likely mediated by _____________ .

Select one:

a. increase the catalytic efficiency of enzyme X not through protein kinase A; elevated cAMP level

b. increase the catalytic efficiency of enzyme X through protein kinase A; stimulate transcription of the gene for enzyme X

c. cannot be determined

d. increase the catalytic efficiency of enzyme X not through protein kinase A; stimulate transcription of the gene for enzyme X

e. increase the catalytic efficiency of enzyme X through protein kinase A; elevated cAMP level

1. Suppose a researcher, interested in obtaining an estimate of the average level of some enzyme in a certain human population, takes a sample of 36 individuals, determines the level of the enzyme in each, and computes a sample mean of 22. Suppose further it is known that the variable of interest is approximately normally distributed with standard deviation of 7. Give a 94% confidence interval of population mean.
2. Suppose we find that, the average engine size in our sample of size n = 30 is 192 cubic inches, with a standard deviation of 104 cubic inches. Use these statistics to compute a 90% confidence interval of population mean, that is, the average engine size for all.
3. Suppose the Dean of our college claims that, the average GPA for all students in the college is at least 3.00, with standard deviation 0.4. However, from a class with 25 students, we find the class average GPA is 2.80. Can we reject the dean’s claim at significance level 0.05? (We conduct a hypothesis testing).

4. a). H0: mu=3.00,          Ha:

   b). Calculate test statistic, here is z-value.

   c). Find pvalue

   d). Make your decision.

How does regulation of glycolysis and gluconeogenesis overlap?

Why is it important that the regulation of glycolysis and gluconeogenesis be coordinated?

Describe the Aerobic Glycolysis and its function in the cell?

Show the math of ATP production/ consumption in glycolysis.

1. Why do ions have a difficult time getting through plasma membranes despite their small size? How are ions transported through biological membranes?
   
2. Where does the cell get energy for active transport processes?
   
3. Describe the position of the transition state on a vertical energy scale, from low to high, relative to the position of the reactants and products, for both endergonic and exergonic reactions. How do enzymes affect the energy of the reactants, product, and transition state.
   
4. Do you think that the E_A for ATP hydrolysis is relatively low or high? Explain your reasoning.

5. Explain in your own words the difference between a spontaneous reaction and one that occurs instantaneously, and what causes this difference.

6. Nearly all organisms on Earth carry out some form of glycolysis. How does this fact support or not support the assertion that glycolysis is one of the oldest metabolic pathways?

7. What is the primary goal of glycolysis and the citric acid cycle (think about what is being produced and what it is used for)?
   
8. Why is it important to have regulatory control over metabolic pathways like glycolysis?