Glucose Metabolism Flashcards
Fatty acids, ketone bodies, glucose, pyruvate, amino acid alanine, and ethanol all get converted into ____ to undergo oxidation and produce fuel
Acetyl CoA
2 carbons from _____ get oxidized into carbon dioxide in the ____ cycle
Acetyl CoA
TCA
____ is a fundamental energy generating pathway shared by all cells. Glucose is converted into 2 molecules of _____
Glycolysis
Pyruvate
_____ glycolysis is the conversion of glucose into 2 molecules of pyruvate and then into 2 molecules of lactate. This generates 2 ____ per glucose. 2 NAD+ become reduced to 2 ____. This process occurs in the ____, outside of the mitochondria
Anaerobic
ATP
NADH
Cytoplasm
Glucose has to get in to our cells. GLUT 1 and 3 or ____, meaning every cell uses them to transport glucose past the membrane. They have a very ___ affinity for glucose
Ubiquitous
High
GLUT _____ is found in the liver and pancreas. It has a ____ affinity for glucose. This means the liver only uptakes glucose when glucose is ____ concentrated in the blood, usually after a meal.
2
Lower
Highly
Glucose is transported across plasma membrane by ____ diffusion, which are the GLUTs or by active transport via ____, using the sodium concentration gradient
Facilitated
SGLT
SGLT is found in the ____ cells and ____ cells. They have a high affinity for glucose
Intestinal epithelial
Kidney epithelial
GLUT __ is insulin dependent. It has a ____ affinity for glucose
4
Medium
The ___ state is right after a meal about 2 or 3 hours. The ___ state is overnight without eating. The ___ state is prolonged fasting. ______ is a metabolic response to major trauma
Fed
Fasted
Starved
Hypercatabolic
In a fed state, glucose is high in the blood. ____ is active and up taking glucose into the liver and pancreas. ____ is released and activates _____ on other cells to help with intake of glucose.
GLUT 2
insulin
GLUT 4
In a fed state, the liver cells and other cells are using _____ and ____ to convert glucose into fuel.
Glycogenogenesis
Glycolysis
In the fasted state, the ____ supplies glucose to other tissues. _____ is not up taking glucose into the liver. ______ are still up taking glucose into other cells for energy. The liver performs ____ and ____ pathways to produce glucose.
Liver
GLUT 2
GLUT 1 and 3
Glycogenolysis
Gluconeogenesis
Glycolysis uses 1 glucose, 2 NAD+, and 2 ADP + Pi to produce net products: 2 ____, 2 ____, and 2 ____
Pyruvate
NADH
ATP
_____ glycolysis is when pyruvate can enter the tricarboxylic acid cycle. The reducing equivalents of ____ can go to the mitochondria for oxidative phosphorylation
Aerobic
NADH
Glycolysis takes place in the ____. Every cell can generate ATP anaerobically through glycolysis. ___ ___ cells and ___ cells can only use ____ glycolysis because they lack mitochondria
Cytoplasm
Red blood
Retina
Anaerobic
Phase 1 of glycolysis:
The energy _____ phase, requiring 2 ATP. Glucose is converted to __________.
Investment
Fructose 1,6 bis phosphate
Phase II of glycolysis:
Is the energy _____ phase, creating 4 ATPs. 2 triose phosphates are converted into 2 ____
Generating
Pyruvate
The final product of anaerobic glycolysis is ____, not pyruvate. _____ ____ converts lactate back into pyruvate which regenerates ____. This allows glycolysis to continue
Lactate
Lactate dehydrogenase
NAD+
Aerobic glycolysis has a net production of ___ ATP. Pyruvate is transported to the _____ and converted to Acetyl CoA and undergoes the ____ cycle
32
Mitochondria
TCA
______ _____ converts pyruvate into Acetyl CoA, which can then enter the TCA cycle and oxidative phosphorylation. This only occurs under ___ conditions.
Pyruvate dehydrogenase (PDH)
Aerobic
______ phosphorylates glucose into glucose 6 phosphate. This “traps” the glucose in the cell. In liver cells, ____ is used for this step. ____ has a higher Km for glucose.
Hexokinase
Glucokinase
Glucokinase
This graph is showing the difference between Hexokinase and glucokinase
Immediately after a meal, all tissues will uptake glucose and produce ATP. The liver phosphorylates glucose and stores it has glycogen or fatty acids.
While fasting, the liver no longer phosphorylates and stored glucose. Glucose is preserved for use by other tissues.
The second regulatory step: the phosphorylation of fructose 6 phosphate into _________. This is catalyzed by the enzyme _______.
Fructose 1,6 bis phosphate
Phosphofructokinase-1 (PFK-1)
PFK-1 has ____ ATP binding sites. An ATP regulatory site and and active site. ATP acts as both a ___ and an ____ ___ for PFK-1
Two
Substrate
Allosteric inhibitor
Insulin signaling activates PFK-2s _____ domain and increases fructose 2,6 bisphosphate production. Glucagon activates the ______ domain of PFK-2, depleting the fructose 2,6 bisphosphate
Kinase
Phosphatase
The third important regulatory step in glycolysis is the transfer of phosphate from ____ to ___ by phosphoenolpyruvate kinase (PK), creating ATP and pyruvate.
Phosphoenolpyruvate
ADP
There are 4 ____ of pyruvate kinase, encoded by L gene and M gene.
Isoforms
When 2,3 BPB is increased, hemoglobin can give up its oxygen ____.
Easier
Symptoms of ____ ____ can indicate problems with transport or problems downstream from pyruvate. The cell must get all its ATP through glycolysis, with ____ ____ as a product.
Lactic acidosis
Lactic acid
Allosteric activator
Allosteric activator
Substrate and Allosteric inhibitor
