BIOL 1020 Lecture Notes - Atp Synthase, Enzyme, Competitive Inhibition

19. Which of the following is a component of Succinate dehydrogenase in Electron transport chain?

A. Niacin

B. FMN

C. FAD

D. Coenzyme Q

E. Lipoic acid

20. In electron transport the flow of electrons:

A. is bidirectional

B. goes from a high energy state to a low energy state

C. takes place in the outer mitochondrial membrane

D. are used to pump H+ into the mitochondrial matrix

21. Which of the following statements about the electron transport chain is NOT correct

A. It is located in the inner mitochondrion membrane

B. Cytochrome c accepts electrons from complex II

C. Cytochrome c oxidase (complex IV) accepts electrons from Cytochrome c

D. Complex I is called NADH dehydrogenase

E. Coenzyme Q accepts electrons from complex I and complex II

22. In the electron transport chain, the enzyme cytochrome C oxidase:

A. Uses H2O as a substrate

B. Produces HOOH as a product

C. Cannot function if oxygen is absent

D. Accepts electrons from hydrogen ions

E. Uses ADP and Pi as substrates

45. The catalysis mechanism used by lysozyme to break down bacterial cell walls is

acid–base catalysis.

covalent catalysis.

metal cofactor redox catalysis.

induced strain.

unknown.

46. Competitive inhibitors of enzymes work by

fitting into the active site.

fitting into a site other than the active site.

altering the shape of the enzyme.

changing the enzyme into an inactive form.

increasing the activation energy of the enzyme-catalyzed reaction.

47. Nerve gases such as Sarin and malathion

block specific chemical transformations by inactivating specific enzymes.

have reversible effects on animals.

are proteins with a primary structure.

block the energy coupling cycle of ATP.

bond covalently to the active site of the enzyme.

48. How do competitive and noncompetitive enzyme inhibitors differ?

Competitive inhibitors bind to the active site, whereas noncompetitive inhibitors change the shape of the active site.

Competitive inhibitors have a higher energy of activation than noncompetitive inhibitors have.

They function at different pH values.

Noncompetitive enzyme inhibitors contain magnesium, whereas competitive inhibitors contain iron.

Noncompetitive enzyme inhibitors are reversible, whereas competitive inhibitors are irreversible.

3) The hydrolysis of sucrose to glucose and fructose is exergonic. However, if you dissolve sucrose in water and keep the solution overnight at room temperature, there is no detectable conversion to glucose and fructose. Why?

Select one:

a. The change in free energy of the reaction is negative.

b. The activation energy of the reaction is high.

c. The free energy of the products is higher than the free energy of the reactants.

d. This is a condensation reaction.

e. The change in free energy of the reaction is positive.

5) Competitive inhibition differs from non-competitive inhibition in that the ___1___ site is where we see competitive inhibition, while the non-competitive inhibitor __2___.

1. a. allosteric b. non-active c. active d. hydrophillic e. hydrophobic

2.
a. binds to the active site, thus blocking it
b. binds outside the active site, changing the shape of the enzyme
c. binds outside the active site, and blocks the active site

6) Phosphofructokinase is an enzyme, and as such it __1___ of the reaction. It is part of glycolysis, and is an example of an enzyme controlled by inhibition, as high levels of citrate (an intermediate further down the catabolic pathway) turns the enzyme off
(1)Select one:
a. lowers activation energy
b. lowers the ΔG
c. raises the Free Energy
(2)Select one
a. non-competitivenegative feedback
b. irreversible competitivereversible competitive.

15)The reactions in the pathways of glycolysis and the citric acid cycle harvest the high-energy electrons stored in glucose. Therefore, these pathways _______________.

Select one:

a. take place in animal cells, but not in plant cells
b. are catabolic pathways
c. are anabolic pathways
d. involve the reduction of glucose and its metabolic intermediates

21) In an exergonic chemical reaction, the products have less free energy than the reactants (-ΔG). Endergonic reactions require an input of energy (+ΔG). The addition of starting materials and the removal of end products prevent metabolism from reaching final equilibrium. Instead, the cell exists in a state of dynamic equilibrium.

Select one:
True
False