T OR F?
Glycolysis (anaerobic process-doesn’t need O2) occurs
in almost every living cell (cytoplasm).
TRUE
PYRUVATE PROCESSED WITH AND WITHOUT O2 YIELDS WHAT?
WITHOUT....LACTATE
WITH.....ACETYL-COA-->ETS.
RESULTS IN two three-carbon pyruvate units.
GLYCOLYSIS
[]---->[ ]
GLUCOSE IS A 6 SIDED MOLECULE...BROKEN DOWN INTO (2) 3 CARBON UNITS.
Activated when cells need energy-inhibited when plenty of ATP (A FEEDBACK MECHANISM)
GLYCOLYSIS
Process that captures some energy as
2 ATP and 2 NADH
GLYCOLYSIS
WHAT IS THIS?
Adenosine monophosphate
AMP
JUST ADD TO THE PHOSPHATE TO GET DI, TRI.
WHAT IS THIS?
NICOTINAMIDE
WHAT IS THIS?
Nicotinamide Adenine Dinucleotide (NAD)
A CO-ENZYME.
NAD+
NADP+ NOTIC OH(PO23) ON BOTTOM.
FINISH THIS:
WHY DOES ATP GIVE E IF IT TAKES E TO BREAK ITS BONDS?
E PRODUCTS ARE GREATER THAT WHAT IS PUT IN.
ID IRREVERSIBLE AND REVERSIBLE
(THERMODYNAMTICS)
STAGE 1 OF GLYCOLTIC PATHWAY
E INVEST OR PRODUCING?
INVESTMENT WITH ATP---> ADP
T OR F ?
PHOSPLORATION PREVENTS GLUCOSE FROM LEAVING THE CELL.
TRUE
GLYCOLYTIC PATHWAY FORMULA.
D-Glucose + 2 ADP + 2 Pi + 2 NAD+ --->
2 pyruvate + 2 ATP + 2 NADH + 2 H+ + 2 H2O
THE PYRUVATE FROM THE GLYCOLYTIC PATHWAY GOES TO WHAT?
TCA (KREBS) CYCLE
International Union of Biochemistry (IUB) instituted a naming convention for enzymes, based upon WHAT?
the type of chemical reaction catalyzed.
Six major enzyme categories
Oxidoreductases ---ox/red
Transferases---transfer structural group
Hydrolases—break down via hydrolysis
Lyases---groups removed to form a double bond or added to a double bond.
Isomerases---Intramolecular rearrangement
Ligases---Join groups/structures together
Intramolecular rearrangement
WHAT ENZYME?
Isomerases
groups are removed by
elimination to form a double bond or added to a double bond..WHAT ENZYME?
Lyases
EXAMPLE OF Transferases
HEXKINASE
T OR F?
Phosphorylation of glucose (kinase) prevents transport out of the cell and increases reactivity
TRUE
WHAT IS THE FIRST Reaction of the Glycolytic Pathway?
Synthesis of glucose-6-phosphate
-Hexokinase Mg+2 cofactor....ATP -->ADP
-IRREVERSIBLE
-Phosphorylation of glucose (kinase) prevents transport out of the cell and increases reactivity
WHAT IS THE 2ND Reaction of the Glycolytic Pathway?
Conversion of glucose-6-phosphate
to fructose-6-phosphate.
-Conversion of aldose to ketose
-Phosphoglucoisomerase
-REVERSIBLE
WHAT IS THE 3RD Reaction of the Glycolytic Pathway?
Phosphorylation of fructose-6-phosphate
-PFK-1
- irreversible due to a large decrease in free energy (large DELTA G) commits the molecule to glycolysis.
WHAT IS THE 4TH Reaction of the Glycolytic Pathway?
Cleavage of fructose-1,6-bisphosphate.
-Aldolase
-Triose Phosphate Isomerase
-Aldol cleavage giving an aldose and ketose product—get both
WHAT IS THE 5TH Reaction of the Glycolytic Pathway?
Interconversion of glyceraldehyde-3-phosphate and dihydroxyacetone phosphate
-Conversion of ketose to aldose enables all carbons to continue through glycolysis (get to use both haves of glucose’s six carbons)
WHAT IS THE 6TH Reaction of the Glycolytic Pathway?
FROM THIS POINT ON, EVERYTHING IS DOUBLED. THIS IS STEP 2.
Oxidation of glyceraldehyde-3-phosphate
-Creates high-energy phosphoanhydride bond for ATP formation in the next step and NADH for future use.
-Glyceraldehyde-3-phosphate dehydrogenase
WHAT IS THE 7TH Reaction of the Glycolytic Pathway?
Phosphoryl group transfer
-Production of ATP-taking a phosphate group off of glycerate-1-3 bisphosphate
-Phosphoglycerate Kinase
WHAT IS THE 8TH Reaction of the Glycolytic Pathway?
Interconversion of
3-phosphoglycerate and
2-phosphoglycerate (ISOMERATION)
-First step in formation of phosphoenolpyruvate (PEP)
-Phosphoglycerate Mutase
WHAT IS THE 9TH Reaction of the Glycolytic Pathway?
Dehydration of 2-phosphoglycerate
- Production of PEP— lyases (Join groups/structures)
-
Enolase
WHAT IS THE 10TH Reaction of the Glycolytic Pathway?
Synthesis of pyruvate
-Formation of pyruvate and ATP
-Produces a net of 2 ATP, 2 NADH, and
2 pyruvate
- Pyruvate Kinase
END PRODUCTS OF THE Glycolytic Pathway
4 ATP, BUT YOU USE 2....FINAL PRODUCT 2 ATP
2 NADH,
2 pyruvate
Under --------- conditions, pyruvate is converted to ------ for use in the citric acid cycle and electron transport chain.
aerobic
acetyl-CoA
IF NOT O2, PYRUVATE ENDS UP AS WHAT?
ETHANOL.
CH3CH2 OH
FERMENTATION
IF NOT O2, BUT NADH, PYRUVATE ENDS UP AS WHAT?
LACTATE ACID VIA HOMOLATIC FERMENTATION.
- Regenerates NAD+ so glycolysis can continue..GET SOME ATP.
The rate of the glycolytic pathway is controlled by three
enzymes (reactions irreversible): 3 NAME THEM AND 2 HORMONES.
Hexokinase
PFK-1
Pyruvate kinase
The hormones are glucagon and insulin
PFK-1 and pyruvate kinase ACTIVATE WHEN?
HIGH AMP CONCENTRATIONS
Glucose-6-phosphate inhibits ---------- and ATP inhibits all 3 enzymes.
hexokinase
Usually occurs when glycogen is depleted in liver (exercise or fasting or starving)
Gluconeogenesis
DEFINE Gluconeogenesis
the formation of new glucose molecules from precursors in the liver
WHAT Requires 4 ATP and 2 GTP (Guanosine triphosphate)?
Gluconeogenesis
THIS PROCESSES Precursors include: lactate, pyruvate, glycerol, alanine and a-keto acids.
Gluconeogenesis
T OR F ?
Gluconeogenesis Reactions ARE THE Reverse of glycolysis except the three irreversible reactions
TRUE
WHAT IS THIS? WHERE DO YOU SEE IT?
ALDOSE.
GLYCOLSIS.
STEP 2 RXN 6
WORD ENDINGS:
ATE VS IC
ATE: PROTENATED
IC: DEPROTENATED
WHERE DOES GLYCOLYSIS OCCUR?
PANCREASE
Gluconeogenesis OCCURS WHERE?
LIVER
THE BRAIN AND RBC MAIN ENERGY SOURCE
GLUCOSE
Three bypass reactions OF Gluconeogenesis.
1. Synthesis of phosphoenolpyruvate (PEP) via the enzymes pyruvate carboxylase and PEP carboxykinase. NEAR BOTTOM
2. Conversion of fructose-1,6-bisphosphate to fructose-6-phosphate via the enzyme fructose-1,6-bisphosphatase. 3RD FROM TOP.
3. Formation of glucose from glucose-6-phosphate via the liver and kidney-specific enzyme glucose-6-phosphatase. NEXT TO SECOND STEP.
DEFINE CORI CYCLE
WHEN LACTATE IS RELEASED FROM SKELETAL MUSCLE
Three of the most important substrates
for gluconeogenesis are:
LACTATE
GLYCEROL
ALANINE
After transfer to the liver ------- is converted to------- then to --------.
After transfer to the liver lactate is converted to pyruvate then to glucose
a product of fat metabolism
Glycerol
BREAKDOWN OF LIPIDS
generated from pyruvate in exercising muscle
—muscle broken down to provide energy
ALANINE
------ is converted to pyruvate then
glucose in the liver
Alanine
THE GLUCOSE ALANINE CYCLE IS PART OF WHAT PROCESS?
GLUCONEOGENESIS
WHAT IS IT?
THE GLUCOSE ALANINE CYCLE
Pentose Phosphate Pathway...PRODUCTS
NO ATP is generated
Products are NADPH and ribose-5-phosphate.
NADPH...LIPID METABOLISM
NAME THE 2 PHASES OF THE PENTOSE PHOSPHATE PATHWAY
oxidative and nonoxidative
NAME THE 2 PRODUCTS OF THE Pentose
Phosphate Pathway: Oxidative
ribulose-5-phosphate and two NADPH
NADPH is a reducing agent used in
anabolic (BUILD UP) processes-lipid biosynthesis
NAME THE 2 PRODUCTS OF THE PentosePhosphate Pathway: NON-Oxidative
Produces important intermediates for nucleotide
biosynthesis and glycolysis
-Ribose-5-phosphate
-Glyceraldehyde-3-phosphate
If the cell requires more NADPH than
ribose molecules, products of the nonoxidative phase can be shuttled into glycolysis.
WHAT PROCESS?
Pentose Phosphate Pathway
WHEN YOU LOSE A H+ WHAT IS IT CALLED?
OXIDATED.
LEO
Most common sugars found in oligosaccharides besides glucose
Fructose and mannose are also important sugars for
vertebrates
Fructose Can enter the glycolytic pathway in two ways
-Through the liver (multi-enzymatic process)
-Muscle and adipose tissue (hexokinase)
ADIPOSE: body fat or fat depot or just fat is loose connective tissue
Second to glucose in the human diet
FRUCTOSE
---------- Synthesis of glycogen, the storage
form of glucose, occurs ------------
Glycogenesis
occurs after a meal
IN WHAT PHASE OF THE PENTOSE PHOSPHATE PATHWAY IS RIBOSE MADE AND WHAT IS IT USED FOR?
Ribose-5-phosphate IS AT THE TOP OF THE PATHWAY. IT CAN GO EITHER WAY, BUT NONOXIDATIVE PHASE Ribose-5-phosphate PRODUCED IS USED FOR BIOSYNTHESIS.
------ & ---------- are also important sugars for
vertebrates
Fructose and mannose
GLYCOGEN IS A BIG POLYMER OF WHAT
GLUCOSE.
GLYCOGENESIS 3 STEPS
1. Synthesis of glucose-1-phosphate (G1P) from glucose-6-phosphate by phosphoglucomutase
2. Synthesis of UDP-glucose from G1P by UDP-glucose phosphorylase
§Synthesis of Glycogen from
UDP-glucose requires two enzymes:Glycogen synthase (LENGTH) & glucosyl transferase (BRANCHES)
NAME THE 2 GLOCOSDIC LINKAGES INVOLED IN GLYCOGENESIS.
ALPHA 1,4 (LENGTH)
ALPHA 1,6 (BRANCHES)
Branching enzyme Amylo-a(1,4à1,6)-glucosyl transferase creates a(1,6) linkages for branches
Glycogen degradation requires two reactions
1. Removal of glucose from nonreducing ends (glycogen phosphorylase) within four glucose of a branch point (off alpha1-6 side chains) and along the main chain.
2.Hydrolysis and transfer to nonreducing end and breaking a(1,6) glycosidic bonds at branch points by amylo-a(1,6)-glucosidase (debranching enzyme)
WHAT IS THE REDUCING AND NONREDUCING ENDS OF GLYCOGEN CHAIN?
THE 1ST CARBON REDUCING
4TH CARBON NON REDUCING.
IN GLYCOGENESIS, WHAT ENZYME IS NEEDED TO CONSTRUCT THE BRANCHES?
glucosyl transferase
WHAT # OF UNITS IS INVOLEVED WITH GLYCOGEN PHOSPHORYLASE.
WHAT ENZYME IS RESPONSIBLE FOR THIS?
Amylo-a(1,6)-glucosidase
WHEN BREAKING DOWN GLYCOGEN, WHAT 2 ITEMS ARE NEEDED TO BREAK DOWN THE CHAIN? (NOT BRANCHES)
Amylo-a(1,6)-glucosidase AND H20 (HYDROLYSIS)
AS A RESULT FROM BREAKING DOWN GLYCOGEN, NAME TWO PLACES PRODUCTS GOTO.
GLYCOLYSIS
BLOODSTREAM
Regulation of Glycogen Metabolism WHAT DOES IT INVOLVE?
Regulation involves insulin, glucagon, epinephrine, and allosteric effectors
Glucagon activates --------------
MADE IN LIVER
Glucagon activates glycogenolysis
Insulin inhibits ----------- and activates ------------.
OPPOSITE OF EPINEPHRINE.
glycogenolysis
glycogenesis
Epinephrine release activates ----------- and inhibits ---------------.
OPPOSITE OF INSULIN.
