Podcast
Questions and Answers
Hexokinase is found in the liver and pancreatic β cells.
Hexokinase is found in the liver and pancreatic β cells.
False
Glucokinase has a higher $K_m$ compared to hexokinase.
Glucokinase has a higher $K_m$ compared to hexokinase.
True
At low glucose concentrations, glucokinase is primarily responsible for glucose phosphorylation.
At low glucose concentrations, glucokinase is primarily responsible for glucose phosphorylation.
False
Insulin induces the activity of hexokinase.
Insulin induces the activity of hexokinase.
Signup and view all the answers
Feedback inhibition of hexokinase is by fructose-6-phosphate.
Feedback inhibition of hexokinase is by fructose-6-phosphate.
Signup and view all the answers
Hexokinase is the primary enzyme responsible for glucose phosphorylation in the liver.
Hexokinase is the primary enzyme responsible for glucose phosphorylation in the liver.
Signup and view all the answers
Glucokinase has a higher $V_{max}$ compared to hexokinase.
Glucokinase has a higher $V_{max}$ compared to hexokinase.
Signup and view all the answers
Hexokinase is inhibited by glucose-6-phosphate.
Hexokinase is inhibited by glucose-6-phosphate.
Signup and view all the answers
Insulin has no effect on the activity of glucokinase.
Insulin has no effect on the activity of glucokinase.
Signup and view all the answers
Glucokinase is found in most tissues except the liver and pancreatic β cells.
Glucokinase is found in most tissues except the liver and pancreatic β cells.
Signup and view all the answers
Glucokinase is responsible for glucose phosphorylation in most tissues except the liver.
Glucokinase is responsible for glucose phosphorylation in most tissues except the liver.
Signup and view all the answers
Hexokinase has a lower $K_m$ compared to glucokinase, indicating a higher affinity for glucose.
Hexokinase has a lower $K_m$ compared to glucokinase, indicating a higher affinity for glucose.
Signup and view all the answers
Glucokinase is induced by insulin, while hexokinase is not influenced by insulin.
Glucokinase is induced by insulin, while hexokinase is not influenced by insulin.
Signup and view all the answers
Hexokinase is subjected to feedback inhibition by fructose-6-phosphate.
Hexokinase is subjected to feedback inhibition by fructose-6-phosphate.
Signup and view all the answers
The maximum velocity ($V_{max}$) of glucokinase is lower than that of hexokinase.
The maximum velocity ($V_{max}$) of glucokinase is lower than that of hexokinase.
Signup and view all the answers
Glucokinase is responsible for glucose phosphorylation in the liver and pancreatic β cells.
Glucokinase is responsible for glucose phosphorylation in the liver and pancreatic β cells.
Signup and view all the answers
Hexokinase is feedback inhibited by glucose-6-phosphate.
Hexokinase is feedback inhibited by glucose-6-phosphate.
Signup and view all the answers
At high glucose concentrations, hexokinase plays a significant role in storing glucose in the liver.
At high glucose concentrations, hexokinase plays a significant role in storing glucose in the liver.
Signup and view all the answers
The $K_m$ value for hexokinase is higher than that of glucokinase, indicating lower affinity.
The $K_m$ value for hexokinase is higher than that of glucokinase, indicating lower affinity.
Signup and view all the answers
Insulin induces the activity of glucokinase but not hexokinase.
Insulin induces the activity of glucokinase but not hexokinase.
Signup and view all the answers
Study Notes
Hexokinase vs Glucokinase
-
Hexokinase and glucokinase are enzymes responsible for phosphorylating glucose to glucose-6-phosphate.
-
Hexokinase is found in most tissues, except the liver and pancreatic beta cells.
-
Glucokinase is found in the liver and beta cells of the pancreas.
-
Hexokinase has a lower Km, indicating a higher affinity for glucose.
-
Glucokinase has a higher Km, indicating a lower affinity for glucose.
-
Hexokinase has a lower Vmax, indicating a lower capacity to process glucose.
-
Glucokinase has a higher Vmax, indicating a higher capacity to process glucose.
-
Hexokinase is not induced by insulin.
-
Glucokinase is induced by insulin.
-
Hexokinase is feedback-inhibited by glucose-6-phosphate.
-
Glucokinase is feedback-inhibited by fructose-6-phosphate.
-
Glucokinase Deficiency can cause maturity onset diabetes of the young (MODY) and gestational diabetes.
Hexokinase vs Glucokinase
- Hexokinase and glucokinase are enzymes responsible for phosphorylating glucose to glucose-6-phosphate.
- Hexokinase is found in most tissues except the liver and pancreatic beta cells.
- Glucokinase is found in the liver and pancreatic beta cells.
- Hexokinase has a lower Km than glucokinase, meaning it has a higher affinity for glucose.
- Glucokinase has a higher Km than hexokinase, meaning it has a lower affinity for glucose.
- Hexokinase has a lower Vmax than glucokinase, meaning it has a lower capacity for glucose phosphorylation.
- Glucokinase has a higher Vmax than hexokinase, meaning it has a higher capacity for glucose phosphorylation.
- Hexokinase is not induced by insulin, while glucokinase is.
- Hexokinase is inhibited by glucose-6-phosphate, while glucokinase is inhibited by fructose-6-phosphate.
- Hexokinase sequesters glucose in tissues, even when glucose concentrations are low.
- Glucokinase helps to store glucose in the liver at high glucose concentrations.
- Glucokinase deficiency can lead to maturity onset diabetes of the young (MODY) and gestational diabetes.
Hexokinase vs Glucokinase
- Hexokinase and glucokinase are enzymes that catalyze the phosphorylation of glucose to glucose-6-phosphate. This process is essential for glucose metabolism.
- Hexokinase is found in most tissues, while glucokinase is primarily found in the liver and pancreatic beta cells.
- Hexokinase has a lower Km than glucokinase, meaning it has a higher affinity for glucose. This allows hexokinase to effectively use glucose even at low concentrations.
- Glucokinase has a higher Km than hexokinase, meaning it has a lower affinity for glucose. This allows it to effectively sequester glucose and convert it to glycogen for storage in the liver when glucose levels are high.
- Hexokinase is not induced by insulin, while glucokinase is. This makes glucokinase a key player in insulin-mediated glucose uptake in the liver.
- Hexokinase is feedback-inhibited by glucose-6-phosphate, while glucokinase is feedback-inhibited by fructose-6-phosphate. This difference in regulation helps ensure efficient glucose metabolism in different tissues.
- Glucokinase deficiency can lead to Maturity Onset Diabetes of the Young (MODY) and gestational diabetes.
Hexokinase and Glucokinase
- Hexokinase and Glucokinase are enzymes that phosphorylate glucose to glucose-6-phosphate.
- Hexokinase is found in most tissues, except the liver and pancreatic β cells.
- Glucokinase is specific to the liver and pancreatic β cells.
- Hexokinase has a lower Km than Glucokinase, meaning it has a higher affinity for glucose.
- Glucokinase has a higher Km than Hexokinase, meaning it has a lower affinity for glucose.
- Hexokinase has a lower Vmax than Glucokinase, indicating it has a lower capacity for glucose phosphorylation.
- Glucokinase has a higher Vmax than Hexokinase, suggesting it has a higher capacity for glucose phosphorylation.
- Hexokinase activity is not affected by insulin, whereas Glucokinase activity is induced by insulin.
- Hexokinase is inhibited by glucose-6-phosphate, while Glucokinase is inhibited by fructose-6-phosphate.
- Glucokinase deficiency can lead to maturity onset diabetes of the young (MODY) and gestational diabetes.
- Hexokinase facilitates glucose uptake and utilization in tissues, even at low glucose concentrations.
- Glucokinase plays a significant role in glucose storage in the liver, especially at high glucose concentrations.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
This quiz explores the differences between hexokinase and glucokinase, two vital enzymes involved in glucose metabolism. It covers their tissue distribution, affinity for glucose, enzymatic capacity, and responses to insulin as well as their implications in diabetes. Test your understanding of these key concepts in biochemistry!
