AP BIOLOGY

CELL RESPIRATION

GLYCOLYSIS

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
The most important control element in the mammalian glycolytic pathway is
A
Phosphofructokinase
B
Pyruvate Kinase
C
Phosphate Dehyrogenase
D
Pyruvate Carboxylase
Explanation: 

Detailed explanation-1: -PFK1 is the most important control site in the mammalian glycolytic pathway. This step is subject to extensive regulation since it is not only highly exergonic under physiological conditions, but also because it is a committed step – the first irreversible reaction unique to the glycolytic pathway.

Detailed explanation-2: -Fructose 2, 6-bisphosphate is a powerful allosteric regulator of glycolysis that acts to stimulate the activity of 6-phosphofructo-1-kinase (PFK-1), the most important control point in mammalian glycolysis.

Detailed explanation-3: -In glycolysis, phosphofructokinase (PFK) is a key regulator of the overall reactions. It exists as a tetramer and each subunit has two binding sites for ATP. This enzyme catalyzes the first unique step in glycolysis, converting fructose-6-phosphate to fructose-1, 6-bisphosphate.

Detailed explanation-4: -phosphofructokinase, enzyme that is important in regulating the process of fermentation, by which one molecule of the simple sugar glucose is broken down to two molecules of pyruvic acid.

Detailed explanation-5: -Three reactions are control points in the glycolysis process. They are hexokinase reactions, pyruvate kinase reactions, phosphofructokinase reactions. These reactions are said to be the control points as they are not reversible, which means these reactions are one-directional.

There is 1 question to complete.