Back to notes
What is gluconeogenesis and where does it primarily occur?
Press to flip
Gluconeogenesis is the formation of glucose from non-carbohydrate sources, and it primarily occurs in the liver.
How does insulin action facilitate glucose uptake in muscle and adipose tissue?
Insulin binds to its receptors on cells, signaling the translocation of GLUT4 to the cell membrane, thereby increasing glucose uptake.
Where in the cell does glycolysis occur?
In the cytosol of the cell.
What is the primary function of glycolysis in cellular metabolism?
To break down glucose into two molecules of pyruvate, releasing energy captured as ATP and NADH.
What is the difference between GLUT1/GLUT3 and GLUT4 transporters?
GLUT1/GLUT3 are high-affinity transporters responsible for basal glucose uptake. GLUT4, however, is insulin-dependent and found in skeletal muscles and adipose tissues, increasing glucose uptake in response to insulin.
What are glucose transporters (GLUT) and what role do they play in glycolysis?
GLUT are proteins that facilitate the uptake of glucose into cells through facilitated diffusion, aiding in the beginning steps of glycolysis.
Describe the significance of glycogenesis and glycogenolysis in liver function.
Glycogenesis is the storage of glucose as glycogen, while glycogenolysis is the breakdown of glycogen to release glucose, both crucial for maintaining blood glucose levels.
What is the role of GLUT2 in liver and pancreatic beta cells?
GLUT2 allows bidirectional movement of glucose. In liver cells, it is involved in glucose storage and release. In pancreatic beta cells, it senses blood glucose levels to regulate insulin secretion.
What high-affinity transporters are involved in basal glucose uptake in the CNS?
GLUT1 and GLUT3 are high-affinity transporters involved in basal glucose uptake in the CNS.
Explain the process of facilitated diffusion in glucose transport.
Facilitated diffusion involves glucose moving from a high to low concentration area through GLUT proteins without energy expenditure.
How does GLUT4 transporters' function differ from that of GLUT1?
GLUT4 transporters are insulin-dependent and are primarily found in muscle and adipose tissue. GLUT1 transporters are independent of insulin and are responsible for basal glucose uptake in a variety of tissues.
How does aerobic glycolysis compare to anaerobic glycolysis in terms of energy release?
Aerobic glycolysis releases significantly more energy than anaerobic glycolysis because pyruvate enters the Krebs cycle and undergoes further oxidation.
What are the two types of glycolysis and their respective end products?
Aerobic glycolysis results in pyruvate entering the Krebs cycle with a large amount of energy released. Anaerobic glycolysis results in pyruvate being converted into lactic acid with less energy released.
Why do red blood cells predominantly perform anaerobic glycolysis?
Because they lack mitochondria.
What is the role of GLUT5, and how is it different from other glucose transporters?
GLUT5 is primarily a fructose transporter, not a glucose transporter, and is found in jejunum cells and testicular cells.
Previous
Next