17 August 2014

Enzymatic Checkpoints/Controls of Glycolysis: Medical School Biochemistry

Earlier videos explained that enzymes that catalyze irreversible steps in glycolysis are considered to be checkpoints:
This video explores how each of those checkpoints works and exactly what metabolites can up-regulate and down-regulate each enzyme activity.

Futile Cycles: Medical School Biochemistry


What is a futile cycle? How do these "so-called" futile cycles help maintain constancy in the cells?
In one "so-called" futile cycle, the levels of phosphate in a cell are maintained at a fairly constant rate by preventing hexokinase from sequestering all of it during high sugar meals.
- The concept of a futile Cycle
- The purposes of futile cycles (why most of them aren't really futile)
- The specific futile cycle will be the G6P-Glucose cycle

Hepatic Regulation of Glucose: Medical School Biochemistry



How does the liver keep from using up all of its glucose to create ATP like the other cells do? How does the liver maintain a glucose concentration similar to that of the blood, while other cells immediately convert glucose into Glucose-6-phosphate?
-Learn how the Michaelis constant (Km) of enzymes in the liver mediates activities differently than in other cells.
-Learn how Glucose transporters in the liver are distinguished from those in other cells