Glucose Metabolism

Question 1

Fatty acids, ketone bodies, glucose, pyruvate, amino acid alanine, and ethanol all get converted into ____ to undergo oxidation and produce fuel

Answer 1

Acetyl CoA

Question 2

2 carbons from _____ get oxidized into carbon dioxide in the ____ cycle

Answer 2

Acetyl CoA
TCA

Question 3

____ is a fundamental energy generating pathway shared by all cells. Glucose is converted into 2 molecules of _____

Answer 3

Glycolysis
Pyruvate

Question 4

_____ 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

Answer 4

Anaerobic
ATP
NADH
Cytoplasm

Question 5

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

Answer 5

Ubiquitous
High

Question 6

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.

Answer 6

2
Lower
Highly

Question 7

Glucose is transported across plasma membrane by ____ diffusion, which are the GLUTs or by active transport via ____, using the sodium concentration gradient

Answer 7

Facilitated
SGLT

Question 8

SGLT is found in the ____ cells and ____ cells. They have a high affinity for glucose

Answer 8

Intestinal epithelial
Kidney epithelial

Question 9

GLUT __ is insulin dependent. It has a ____ affinity for glucose

Answer 9

4
Medium

Question 10

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

Answer 10

Fed
Fasted
Starved
Hypercatabolic

Question 11

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.

Answer 11

GLUT 2
insulin
GLUT 4

Question 12

In a fed state, the liver cells and other cells are using _____ and ____ to convert glucose into fuel.

Answer 12

Glycogenogenesis
Glycolysis

Question 13

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.

Answer 13

Liver
GLUT 2
GLUT 1 and 3
Glycogenolysis
Gluconeogenesis

Question 14

Glycolysis uses 1 glucose, 2 NAD+, and 2 ADP + Pi to produce net products: 2 ____, 2 ____, and 2 ____

Answer 14

Pyruvate
NADH
ATP

Question 15

_____ glycolysis is when pyruvate can enter the tricarboxylic acid cycle. The reducing equivalents of ____ can go to the mitochondria for oxidative phosphorylation

Answer 15

Aerobic
NADH

Question 16

Glycolysis takes place in the ____. Every cell can generate ATP anaerobically through glycolysis. ___ ___ cells and ___ cells can only use ____ glycolysis because they lack mitochondria

Answer 16

Cytoplasm
Red blood
Retina
Anaerobic

Question 17

Phase 1 of glycolysis:
The energy _____ phase, requiring 2 ATP. Glucose is converted to __________.

Answer 17

Investment
Fructose 1,6 bis phosphate

Question 18

Phase II of glycolysis:
Is the energy _____ phase, creating 4 ATPs. 2 triose phosphates are converted into 2 ____

Answer 18

Generating
Pyruvate

Question 19

The final product of anaerobic glycolysis is ____, not pyruvate. _____ ____ converts lactate back into pyruvate which regenerates ____. This allows glycolysis to continue

Answer 19

Lactate
Lactate dehydrogenase
NAD+

Question 20

Anaerobic glycolysis has a net generation of ____ ATP per 1 glucose molecule. Glucose to ___.

Answer 20

2
Lactate

Question 21

Aerobic glycolysis has a net production of ___ ATP. Pyruvate is transported to the _____ and converted to Acetyl CoA and undergoes the ____ cycle

Answer 21

32
Mitochondria
TCA

Question 22

______ _____ converts pyruvate into Acetyl CoA, which can then enter the TCA cycle and oxidative phosphorylation. This only occurs under ___ conditions.

Answer 22

Pyruvate dehydrogenase (PDH)
Aerobic

Question 23

In order to maximize the energy yield from glycolysis, the ____ produced by glyceraldehyde 3 phosphate dehydrogenase must be converted into _____ reducing agents

Answer 23

NADH
mitochondrial

Question 24

The reactions that regulate glycolysis are ______, ______, and ____ ____. They are strongly exergonic and essentially ____.

Answer 24

Hexokinase/glucokinase
Phosphofructokinase-1
Pyruvate kinase
Irreversible

Question 25

______ 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.

Answer 25

Hexokinase Glucokinase Glucokinase

Question 26

This graph is showing the difference between Hexokinase and glucokinase

Answer 26

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.

Question 27

Glucokinase has a ____ Km than Hexokinase. Hexokinase has a ____ affinity for glucose than glucokinase.

Answer 27

Higher Higher

Question 28

The second regulatory step: the phosphorylation of fructose 6 phosphate into _________. This is catalyzed by the enzyme _______.

Answer 28

Fructose 1,6 bis phosphate Phosphofructokinase-1 (PFK-1)

Question 29

PFK-1 has ____ ATP binding sites. An ATP regulatory site and and active site. ATP acts as both a ___ and an ____ ___ for PFK-1

Answer 29

Two Substrate Allosteric inhibitor

Question 30

Phosphofructokinase-1 is the ___ ___ step in the glycolysis pathway. When ATP is high, the ____ sites are bound which stops the glycolysis pathway. When ATP is low and AMP is high, the ____ sites are bound and glycolysis can persist

Answer 30

Rate limiting Inhibitory Active

Question 31

____ and ____ bind to the inhibitory sites of PFK-1. ___ and ___ bind to active sites of PFK-1

Answer 31

ATP Citrate AMP fructose 2,6 bisphosphate

Question 32

Fructose 2,6 bisphosphate is not an intermediate of glycolysis, it is a ____ secondary messenger. It is produced by the enzyme _______

Answer 32

Regulatory Phosphofructokinase-2 (PFK-2)

Question 33

PFK-2 activity is substrate regulated. If there are high levels of ______, PFK-2 kinase domain in activated, fructose 2,6 bisphosphate is produced and binds to ____. PFK-1 is activated and fructose 6 phosphate is converted to _______

Answer 33

Fructose 6 phosphate PFK-1 Fructose 1,6 bisphosphate

Question 34

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

Answer 34

Kinase Phosphatase

Question 35

The third important regulatory step in glycolysis is the transfer of phosphate from ____ to ___ by phosphoenolpyruvate kinase (PK), creating ATP and pyruvate.

Answer 35

Phosphoenolpyruvate ADP

Question 36

There are 4 ____ of pyruvate kinase, encoded by L gene and M gene.

Answer 36

Isoforms

Question 37

_______ is not a glycolytic intermediate, it is a second messenger that regulates the activity of hemoglobin in red blood cells.

Answer 37

2,3 bisphosphoglycerate

Question 38

When 2,3 BPB is increased, hemoglobin can give up its oxygen ____.

Answer 38

Easier

Question 39

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.

Answer 39

Lactic acidosis Lactic acid

Question 40

If a cell does not have oxygen, the _____ ratio increases. The ____ ratio increases, AMP acts as an Allosteric activator of PFK-1, the rate of glycolysis is increased.

Answer 40

NADH/NAD+ AMP/ATP

Question 41

The enzymes of glycolysis operate in reverse in _____ with the exception of the key regulatory steps.

Answer 41

Gluconeogenesis

Question 42

Answer 42

Allosteric activator

Question 43

Answer 43

Allosteric activator

Question 44

Answer 44

Substrate and Allosteric inhibitor

Question 45

What molecule is the most sensitive indicator of cellular energy demand?

Answer 45

AMP

Question 46

Which enzyme is the most important regulatory step in glycolysis?

Answer 46

Phosphofructokinase-1

Question 47

Phosphofructokinase-1 is inhibited by _____ and activated by ______

Answer 47

ATP AMP

Question 48

Which transports below has the lowest Km for glucose? GLUT1, GLUT2, or GLUT 4

Answer 48

GLUT1, it has the highest affinity