BCH 451 Fall 2008                                       Exam #4 

1.         (2) Write the net balanced equation for A = glycolysis; B = gluconeogenesis; C = Citric Acid Cycle:

2.         For the chemiosmotic theory,

            a.         (0.3) Who proposed it?

            b.         (1.5) What is this theory?

            c.         (1.5) What experiment(s) help support this theory?

3.         (1) Define T = shuttle; U = shunt

4.         (4) For step of glycolysis, name the enzyme, give the name of the class of the enzyme, draw the structures of the non-cofactor substrate(s) and product(s) connected by the reaction arrows, which show the reversibility or irreversibility, show the co-substrates coming in and out of the reaction as appropriate using the usual abbreviations, and list all other cofactors under the reaction arrow(s):

Enzyme name:                                    Enzyme class:

Reaction:

5.         For step # [insert the number from page one] in glycolysis

            a.         (0.4) Enzyme name:

            b.         (0.6) Regulators and their effects as + or -

            c.         (0.4) Is replaced by this enzyme or enzymes in gluconeogenesis:

            d.         (0.6) Regulators and their effects as + or - of enzyme or enzymes in question “c”:

6.         (0.3 each) Fill in the blanks:

Regulators and their effects (+/-) on enzyme #3 in the TCA cycle

Regulator and its effects on pyruvate dehydrogenase phosphatase

Enzyme which replaces phosphoenol pyruvate carboxylase in animals

Regulator and its effects on enzyme #4 in the TCA cycle

Energy of a glycosidic bond as compared with ATP

Energy of acetyl phosphate as compared with ATP

What the pentose phosphate pathway provides

Regulators and their effects (+/-) on pyruvate dehydrogenase

Standard free energy of hydrolysis of ATP

Enzyme which requires K⁺ for activity

Name of bond in phosphocreatine which is hydrolyzed

How NADH “enters” the mitochondrial matrix

7.         (4) For step of the Krebs cycle, name the enzyme, give the name of the class of the enzyme, draw the structures of the non-cofactor substrate(s) and product(s) connected by the reaction arrows, which show the reversibility or irreversibility, show the co-substrates coming in and out of the reaction as appropriate using the usual abbreviations, and list all other cofactors under the reaction arrow(s):

Enzyme name:                                    Enzyme class:

Reaction:

8.         For complex in oxidative phosphorylation,:

(0.3)    full and complete name of the complex:

(0.2)    number of protons which enter the complex from the matrix:

(0.2)    number of protons pumped out of the complex into the inner membrane space:

(0.4)    substrates and/or co-substrates [full names and not abbreviations; no structures]:

(0.4)    products and/or “co-products” [full names and not abbreviations; no structures]:

(0.6)    prosthetic groups:

9.         Definitions:

            a.         (1) F = cofactor; N = coenzyme; S = co-substrate; P = prosthetic group

            b.         (1) M = Metabolism; B = Metabolite; P = pathway;

10.       (2) What is substrate level phosphorylation and give one example

11.       (2) PUZZLER Approximately 30 years ago, the soft drink manufacturers started removing sucrose and replacing it with high fructose corn syrup. This shift has permeated to many foods. About the same time, obesity and incidence of diabetes started to increase. Based on your knowledge of sugar metabolism, suggest a reason why these increases might be linked to the change in the nature of sweeteners. [Continue on the back of this page as necessary.]

This page of the exam is for lecture section 001 only

12.       (2) Describe how F = fructose, G = galactose, M = mannose, L = glycerol, or N = glycogen by using the names of all of the enzymes.

13.       For A = adenylate kinase or N = nucleoside diphosphokinase,

            a.         (0.7) Where specifically and in detail is it found?

            b.         (1) What reaction does it catalyze?

14.       For L = phosphoenol pyruvate carboxylase or K = phosphoenol pyruvate carboxykinase,

            a.         (0.7) Where specifically and in detail is it found?

            b.         (0.6) In what pathway(s) is it found?

            c.         (1) What reaction does it catalyze?

This page of the exam is for lecture sections 002 and 003 only

15.       (2) Describe how F = fructose, G = galactose, M = mannose, L = glycerol, or N = glycogen by using the names of all of the substrates, products, and enzymes.           

16.       For the glyoxylate shunt,

            a.         (0.3 each) What are the enzymes which are used by other pathways?

            b.         (0.3 each) What are the enzymes which are unique to this pathway?

            c.         (0.3) What is the carbon product of this pathway?

            d.         (1.2) Based on these enzymes, write a balanced reaction for this pathway:

            e.         (0.5) Why is it called a shunt?