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Biochem: 1. Starting with one molecule of glucose, draw out the process that is

ID: 72075 • Letter: B

Question

Biochem:

1. Starting with one molecule of glucose, draw out the process that is needed to convert this into two pyruvate.

2. A patient is in for a follow up visit after having a myocardial infarction two months ago. Based on her angiogram immediately after recovering from the MI, it was noted that she had obstruction in the distal portion of her Left Anterior Descending artery which reduced oxygen delivery to the apical and mid region of her left ventricle and also makes lactate removal difficult.

a. Low levels of oxygen leads to decreased levels of ATP which result in high levels of AMP. Explain what would in these cells with respect to glycolysis using the information presented in the case above.

b. During the angiogram a stent was placed in the distal LAD to improve blood flow to the left ventricle. Explain why this helped the patient recover from her MI.

3. Suppose there is a mutation in the active site of Triose Phosphate Isomerase that does not allow it to complete its activity. What is the net energy yield in glycolysis from 1 glucose molecule assuming the rest of glycolysis functions normally?

4. Some of the enzymes found in the active site of lactate dehydrogenase are presented below. Suppose a R171Q mutation is observed. Explain the effects of this mutation on glycolysis.

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3. Suppose there is a mutation in the active site of Triose Phosphate Isomerase that does not allow it to complete its activity. What is the net energy yield in glycolysis from 1 glucose molecule assuming the rest of glycolysis functions normally?

4. Some of the enzymes found in the active site of lactate dehydrogenase are presented below. Suppose a R171Q mutation is observed. Explain the effects of this mutation on glycolysis.

5. How might a Cytosolic glycerol 3P dehydrogenase deficiency affect aerobic glucose metabolism?

6. An individual has a mutation in pancreatic glucokinase that yields the following kinetic curve. How might this mutation affect the individual? What tissues will be most affected?

Orange = mutated glucokinase

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6. An individual has a mutation in pancreatic glucokinase that yields the following kinetic curve. How might this mutation affect the individual? What tissues will be most affected?

7. During fasting conditions, which of the following would be true

DecreasedF2,6 BisP levels in Liver

High extracellular lactate concentration

Hydrolyzed phosphatase

Domain of PFK-2

Increased protein kinase A activity in muscle

Increased Glucokinase concentration in the nucleus

High intracellular AMP

Increased ETF activity

A

Yes

Yes

Yes

No

Yes

No

No

B

Yes

No

Yes

No

Yes

No

Yes

C

Yes

Yes

Yes

Yes

No

Yes

Yes

D

Yes

No

Yes

No

Yes

No

No

E

No

Yes

No

Yes

No

Yes

Yes

F

No

No

No

Yes

Yes

No

No

G

No

Yes

Yes

No

No

Yes

Yes

8. Explain the relationship between oxygen delivery to the heart and activity of the glycolytic pathway as it relates to high 2,3 BPG concentrations. Does this make sense?

DecreasedF2,6 BisP levels in Liver

High extracellular lactate concentration

Hydrolyzed phosphatase

Domain of PFK-2

Increased protein kinase A activity in muscle

Increased Glucokinase concentration in the nucleus

High intracellular AMP

Increased ETF activity

A

Yes

Yes

Yes

No

Yes

No

No

B

Yes

No

Yes

No

Yes

No

Yes

C

Yes

Yes

Yes

Yes

No

Yes

Yes

D

Yes

No

Yes

No

Yes

No

No

E

No

Yes

No

Yes

No

Yes

Yes

F

No

No

No

Yes

Yes

No

No

G

No

Yes

Yes

No

No

Yes

Yes

Explanation / Answer

1.

Glycolysis is the main metabolic process that produces energy in the form of ATP (adenosine triphosphate). This process meets the metabolic requirements of cell proliferation. Hence, glycolysis is intensified during cell proliferation. During glycolysis, one glucose molecule splits into two pyruvate molecules. This pyruvate enters into TCA cycle after converted to acetyl CoA.