Biochemistry:
Why does gluconeogenesis bypass hexokinase (the first enzyme of glycolysis)? Specific reason please.
Biochemistry: Why does gluconeogenesis bypass hexokinase (the first enzyme of glycolysis)? Specific reason please.
In detail, please describe gluconeogenesis in simple terms, describe what the difference is between it and why it's not reverse glycolysis, and descirbe it's first bypass (bypass 1) in mitochondria.
1. Hexokinase II (the isoform usually discussed in biochemistry classes as part of glycolysis) catalyzes the first step in glycolysis. The isoform of hexokinase that is expressed in most tumor cells is bound to the mitochondrial outer membrane facing the cytosol. Propose two reasons why this would be beneficial to the tumor cell. 2. Another highly regulated enzyme in glycolysis is phosphofructokinase (PFK1). There is evidence from some tumors that PFK1 undergoes a posttranslational proteolysis that yields a truncated functional...
Which of the following enzyme catalyzes the first step of glycolysis? * Hexokinase Pyruvate kinase Glucokinase Phosphofructokinase-1
QUESTION 25 Why does gluconeogenesis utilize several unique steps compared to glycolysis? a. it doesn't; gluconeogenesis is a direct reversal of glycolysis b. to overcome large energy barriers at those steps gluconeogenesis does not involve NAD/NADH, unlike glycolysis d. the unique steps in gluconeogenesis do not require any enzymes
Need some help with this question Gluconeogenesis is not quite the exact reverse process of glycolysis, as three key biosynthetic steps used in glycolysis must be bypassed when performing gluconeogenesis. Why are the bypasses of the first and third steps of glycolysis,used in gluconeogenesis, easier to achieve than bypass of the last step?
1. Bypassing the pyruvate kinase reaction. Gluconeogenesis and glycolysis are opposing pathways that share seven enzymes. The exergonic steps in glycolysis cannot be simply reversed because that would be too energetically costly. Thus, these steps are "bypassed" in gluconeogenesis with a separate set of enzymes. a. Explain why the reaction catalyzed by pyruvate kinase is energetically favorable and essentially irreversible in the cells. b.Explain how the cells that run gluconeogenesis are able to bypass this step with specific reactions that...
How many of the 10 glycolysis reactions use the same enzyme in the gluconeogenesis pathway? a. 10 b. 7 c. 5 d. 3 S The first step in gluconeogenesis is the conversion of pyruvate into oxaloacetate. This is reaction that requires aprosthetic group. a. an oxidative decarboxylation, THF b. a redox, NADH c. a phosphate transfer, chlorophyll d. a carboxylation, biotin
5. What is Gluconeogenesis? Where does it mainly take place in our body? Why does three exergonic steps in gluconeogenesis bypass in gluconeogenesis? Why gluconeogenesis is expensive? Why is it essential?
A decrease in oxidative phosphorylation also leads to a decrease in reactive oxygen species (ROS). Why might this be an advantage for cancer cells? What are the three major metabolic control points in glycolysis? What generic reaction do these enzymes perform? Why are these enzymes the ones most regulated? Hexokinase II (the isoform usually discussed in biochemistry classes as part of glycolysis) catalyzes the first step in glycolysis. The isoform of hexokinase that is expressed in most tumor cells is...
please explain answer Glycolysis. In the third step of glycolysis, the enzyme phosphofructokinase transfers a phosphate group from ATP to fructose-6-phophate to generate fructose- 1,6- bisphosphate. In contrast, in step 10, the enzyme pyruvate kinase transfers a phosphate group from phosphoenolpyruvate to ADP to generate ATP. Using what you know about the standard free energy change associated with phosphate bonds, (briefly) explain why we observe this difference.