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Flashcards in OldFInal Deck (17)
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1

two of the three steps are regulated in glycolysis. what are these?

Hexokinase (1st step)
Phosphofructokinase-1 (3rd step)

2

In the first regulated step (1st step), the produce of the reaction glucose 6-phosphate inhibits the enzyme that catalyzes its own formation. What is the reason for this type of regulation

This is feedback inhibtion
-occurs to prevent accumulation of glucose 6-phosphate
-to maintain high levels of glucose if the use of glucose 6-phosphate is inhibited

3

Given the cure for relative velocity vs {Glucose} for the fist enzyme shown. Adding glucose 6-phosphate to the recant will shift the curve how? What if the Michaelis mention behavior instead, draw the curve.

DRAW ON TABLE
-look desktop

4

Glucagon is a hormone secreted by the pancreas in response to low blood glucose levels. Describe at least 3 mechanisms that are induced by glucagon to restore blood glucose to normal levels.

1)Glucagon activates cAMP synthase and cAMP activates PKA, PKA phosphoryltes pyruvate kinase, so last step in glycolysis is inhibited

PKA phosphorylates glycogen phosphorylase and activates it.This induces synthesizing of glucose 1-phosphate from glycogen

Synthesis of glycogen from glucose is inhibited by PKA phosphorylation of glycogen synthase

5

What are two enzymes within the citric acid cycle (after the synthesis of citrate) that are allosterically regulated and whose regulation control the overall oxidation of acetate?

1) Isocitrae dehydrogenase
2) a-ketogluterate dehydrogenase complex

6

List one activator and one inhibitor of isocitrate dehydrogenase

activator:ADP or Ca2+
inhibitor: ATP

7

List one activator and one inhibitor of a-ketogluteral dehydrogenase complex

Activator: Ca2+
Inhibitor: Succinyl-CoA or NADH

8

What can happen to citrate if its further reaction in the citric acid cycle is impeded?

There is a transporter for exporting citrate to the cytosol
-and citrate in the cytosol will be broken down to oxaloacetate and acetyl-CoA production

9

In the mechanism oxidative phosphorylation, what is the most highly reduced metabolite involved in the electron flow involved in complexes II, III, and IV?

Succinate reacting at complex II

10

In the mechanism oxidative phosphorylation, what is the most highly reduced metabolite involved in the electorn flow involved in complex III

FADH2

11

For complex IV, what is the initial reduced metabolite for electron flow and what is the last reduced metabolite?

Cytochrome (c) is initial reduced metabolite
H20 is last reduced metabolite

12

How does the electron flow through complex III contribute to proton-motive force?

There are 4H+ transfered

13

Is the ATP that is synthesized in oxidative phosphorylation in the eukaryotic cell in the correct cellular location for gluceoneogenesis? WHY?

NO the ATP is generated in the mitochondrial matrix. Gluceoneogenesis occurs in the cytosol so there has to be transport of ATP out of the MATRIX

14

In the Photosystem II complex in purple bacteria, what is the initial electron donor after absorbance of a photon and what is the final reduced product of the PSII complex?

1) excited primary pigment
2)FADH2 (reduced)

15

How much H+ transport is there during absorbance of photons in the PSII complex

NO H+ is transported in PSII

16

In The PSII system, what its he reduced product form cytochrome bc1 (complex III) and what is the role in the overall photosynthesis mechanism?

the reduced produce of cytochrome bc is cytc c
its roles it to diffuse to PSII and reduce primary photopigment (P870) back to ground state

17

What is the consequence of the absorbance of two photons in the photosystem II mech, prior to the action of ATP synthase?

consequence is the translocaton of 4H+ to inter membrane space