Glycolysis I

Question 1

Glycolysis, the breakdown of glucose, is a catabolic pathway involving ____

Answer 1

involving oxidation and yields ATP energy.

Question 2

Gluconeogenesis, the synthesis of glucose, is an anabolic pathway that involves ____

Answer 2

involves reduction and requires ATP and ATP.

Question 3

Know structures of fructose and glucose compounds, all enzyme names, all molecule names, and reactions I described where the Delta G zero prime is strongly positive, or strongly negative.

Answer 3

CHECK

Question 4

There are ___ reactions in glycolysis.

Answer 4

10 reactions

Question 5

What are the two phases of glycolysis?

Answer 5

Glycolysis has two phases - an energy investment phase and an energy realization phase where ATP is made.

Question 6

In reaction #1 of glycolysis, hexokinase catalyzes __

Answer 6

Hexokinase catalyzes transfer of phosphate to glucose from ATP, forming G6P. Thus, this step uses ATP, which provides the energy necessary for the reaction to proceed.

Question 7

Example of an energy-coupled reaction?

Answer 7

Hexokinase catalyzes transfer of phosphate to glucose from ATP, forming G6P. The Delta G zero prime is strongly negative, thanks to the ATP hydrolysis.

Question 8

Hexokinase changes shape as it binds to glucose. What is this property consistent with?

Answer 8

This property is consistent with that of an induced fit of an enzyme in the process of catalysis.

Question 9

Reaction #2 of glycolysis is catalyzed by __

Answer 9

Reaction #2 of glycolysis is catalyzed by phosphoglucoisomerase.

Question 10

What is converted in Reaction #2?

Answer 10

G6P is converted to F6P. The Delta G zero prime for the reaction is close to zero. Note than a linear intermediate is formed in the process.

Question 11

What is Reaction #3 primarily known for in glycosis?

Answer 11

Reaction #3 is the primary regulatory reaction of glycolysis.

Question 12

Reaction #3 of glycolysis is catalyzed by __

Answer 12

It is catalyzed by phosphofructokinase (PFK).

Question 13

What are some characteristics of PFK.

Answer 13

PFK is the most important regulatory enzyme for glycolysis. The molecule made in the process, F1,6BP, is a high energy molecule and the energy in the molecule is needed in the next reaction.

Question 14

What is Reaction #3 an example of?

Answer 14

The reaction is another example of an energy-coupled reaction and the Delta G zero prime is strongly negative, thanks to the ATP hydrolysis.

Question 15

Reaction #4 of glycolysis is catalyzed by __

Answer 15

Reaction #4 is catalyzed by aldolase.

Question 16

What are the products in Reaction #4?

Answer 16

The products of this reaction are G3P and DHAP.

Question 17

What is the Delta G of Reaction #4 like? What occurs because of this?

Answer 17

It has a strongly positive Delta G zero prime. In the cell, however, the reaction is pulled by reactions ahead of it (which remove products) and pushed by reactions behind it (which increase amounts of reactants), making the Delta G favorable (negative).

Question 18

How is the energy barrier of reaction 4 overcome?

Answer 18

The energy barrier of reaction 4 is overcome by ‘pushing’ (increasing concentration of reactatnts) and ‘pulling’ (decreasing concentration of products) of the reaction.