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ENERGY TRANSFER IN THE BODY
PRESENTED BY :SNEHA SHAHMPT 1st YEAR
(NEURO)
The free energy is liberated in the form of ATP hydrolysis reflects the energy difference between the reactant and end products
Because energy from ATP hydrolysis powers all forms of biologic work ,ATP constitutes the cells energy currency
It can react anaerobically without the use of oxygen to form energy for this reason any body movement can happen immediately
The body maintains continuous ATP supply through different metabolic pathways some are located in the cell cytosol while other operate with cell mitocondria
INTRODUCTION
Identify the high energy phosphates and discuss their contributions to powering biologic work
Quantify the body’s reserves of ATP and Pcr Outline electron transport –oxidative
phosphorylation Discuss the role of oxygen in energy metabolism Describe cellular energy release during
anaerobic metabolism Contrast the energy-conserving efficiencies of
aerobic and anaerobic metabolism
OBJECTIVE OF PRESENTATION
Discuss the dynamics of lactate formation and its accumlation in blood during increasing exercise intensity
Indicate the role of the citric acid cycle in energy metabolism
Outline the general pathways for energy release during macronutrient catabolism
Indicate the role of the cori cycle in exercise energy metabolism
Outline diverse interconversions among carbohydrate,fat and protein
Discuss the statement ‘fats burn in a carbohydrate flame’
ATP resynthesis proceeds unintrupted to supply energy for biologic use. Fat and glycogen represent the major energy sources for maintaining continual ATP resyntheses
Some energy directly comes from the anaerobic splitting of a phospate from phosphocreatin the term HIGH ENERGY PHOSPHATE is given to it
PHOSPHOCREATINE: THE ENERGY RESERVOIR
The ATP and Pcr molecules have similar charcteristics a large amount of free energy is been liberated when bond breaks down between Pcr arrow is in both the direction large amount of free energy hydrolysis in Pcr 4 to 6% in mitrochondria and 3 to 5% in sarcomere and 90% in cyctosole
Transient increases in ADP within the muscle’s contractile unit during muscle action shift the creatin kinase reaction towards Pcr hydrolysis and ATP production the reaction does not require oxygen and reaches a maximum energy yield about 10 seconds
ATP ADP+Pi+ENERGY Pcr+ADP cr+ATPATP and Pcr provide anaerobic sources of
phosphate bond .The energy liberated from hydrolysis of Pcr rebonds ADP and Pi to form ATP
Most of the energy for phosphorylation derived from the oxidation of dietry carbohydrate , lipid and protien macronutrients .
Oxidation and reduction reaction takes place that remain coupled because every oxidation coincide in reduction
It constitutes the biochemical mechanism that underlines energy metabolism
This process continuously provide H atom from the catabolisim stored in carbohydrate,fatand protien molecules
CELLULAR OXIDATION
It is generally scheme for hydrogen oxidation and accompanying electron transport to oxygen
NADH and FADH2 is formed in the break down of food provide energy rich molecules because they carry electrons with a high energy transfer potential.
It is a specific molecule constitutes the respiratory chain,The final common pathway where electrons extracted from hydrogen pass to oxygen
Each pair of hydrogen atoms 2 electron flow down the chain and reduce one atom of 0 to form 1water of 5cytochromes only last cytochrome oxidase
Figure represents route for H oxidation,electron transport and energy transfer in the repiratory chain
ELECTRON TRANS PORT CHAIN
ELECTRON TRANSPORT
It is oxydative phosphorylation synthesizes ATP by transfering electrodes from NADH and FADH2 to O
Energy is generated from the reaction from electron transport pump protons across the inner mitochondrial membrane into the inter membrane space
This stores the potential energy It provides the coupling mechanism that bind ADP and a
phosphate ion to synthesize ATP cause the mitochondrial membrane impermiable to ATP the protien complex ATP/ADP translocase exports the synthesised ATP molecule. in turn ADP and Pi into mitocondria this is called CHEMOIOSMOTIC COUPLING ◦ THE REACTION IS
NADH+H+3ADP+3Pi+1/2O2 NAD +H2O +3ATP
OXIDATIVE PHOSPHORYLATION
Availability of the reducing agent NADH in the tissue synthesis
Presence of oxidysing agent O in the tissues Sufficient concentration of enzymes and
mitochondria to ensure that energy transfer reaction proceed at there appropriate rate
OXGEN ROLE IN ENERGY METABOLISM
There are specific pathways of degradation depending upon nuetrient substrate catabolism
It out lines the macro nuitrient fuel sources that supply substrate for oxidation and subsequent formation of ATP these sources are primary of .1Triglyceride and glycogen molecules
2Glucose3FFA4Intramuscular and liver derived carbon skeletons of amino
acids5Anarobic reaction in the cytosol in the initial phase of
glucose 6Phosphorylation of ADP by PCr under enzymatic control by
creatine kinase and adenylate kinase
ENERGY RELEASE FROM FOOD
ENERGY RELEASE FROM THE FOOD
They are primary function is supplying energy for cellular work
They provide macronuitriant substrate whose energy generates ATP anaerobicaly .this becomes important in maximal exercise that requires rapid energy release supplied by aerobic metabolism. intramuscular glycogen supplies energy for ATP
During light and moderate exercise they provide 1/3 of energy to the body
Processing large quantities of fat of energy require catabolism of carbohydrate
Aerobic hydrolysis of carbohydrate for energy occurs more rapidly .thus depleating glycogen reserve significantly reduces exercise power out put
ENERGY RELEASE FROM CARBOHYDRATE
GLYCOLYSIS GENERATES ANAEROBICALY ENERGY FROM GLUCOSE
GLUCOSE GLUCOSE 6 PHOSPHATE FRUCTOSE 6 PHOSPHATE hexokinase glucose phosphate isomerase phospho fructo kinase fructose 1,6 diphosphate aldolase DIHYDROXY ACETONE PHOSPHATE triosephophate isomerase 3 PHOSPHO GYCERALDEHYDE
glyceraldehyde 3phosphate dehydrogenase 1,3 DIPHOSPHO GLYCERATE Phospho glycerate kinase 2 PHOPHOGLYCERATE enalase PHOSPHOENOLE PYRUATE
pyruate kinase PYRUATE LACTATE
Glycolysis :a series of 10 enzymatically controlled chemical reactions create 2 molecules of pyruate from the anaerobic break down of glucose.Lactate forms when NADH oxidation does not keep pace with its formation in glycolysis.enzymes colored yellow purple are those that play a key regulatory role in these metabolic reaction.
Enzymes become inactive following a meal,while glycogen synthase activity increases to facilitate storage of the glucose obtain
Conversely between meals when glycogen reserves decreases ,phosphorylase becomes active to maintain blood glucose for body tissues ,skeletal muscle at rest shows higher synthesis activity ,while activities include phosphorylase activity with blunting of synthase enzyme
Epinephrine accelerates the rate that phosphorylase cleaves one glucose component at a time from the glycogen molecule
METABOLISM OF GLUCOSE TO GLYCOGEN AND GLYCOGEN TO GLUCOSE
IT DEPENDS UPON Concentration of the key glycolytic hexokinase ,
phosphofructokinase and pyruate kinase Levels of the substrate fructos 1,6 diphosphate Oxygen Muscle fibers and adipocytes contain
an insulin dependent transporter known as gluT4 in response to insulin and physical activity GLUT4 migrates from vesicles within the cell to the plasma membrane this facilitates the glucose transport into the sarcoplasm it is used for ATP formation.
REGULATION OF GLYCOLYSIS
In a strennous exercise when energy demands exceeds either O supply ,the respiratory chain cannot process all of the hydrogen joined to NADH continues use can lead to NADH (neg) availability to oxidize 3_phosphoglycraldehyde it catalyses the enzyme lactate dehydrogenase
Its formation is in two ways The energy metabolism of red blood cells that contain no
mitochondria Limitation posed by enzymes activity in muscle fibers with
high glycolytic capacity It starts oxidizing its capacity to heart that is equal to its
rate .
LACTATE FORMATION
There are temporary storage of hydrogen with pyruate that is end product of glycolysis
Lactate forms in the muscles and defuses in the interstitial space and blood for buffering and removal from the site of energy metabolism
Glycolysis continue to supply anaerobic energy for ATP resynthesis.As the load is increased will fatigue by inactivating various enzymes and increase acidity
It provides the valuable source source for intense exercise
When sufficient 0 once again becomes available during recovery .when an exercise is been performed NAD+ is scavenged H attached to lactate for subsequent oxidation to form to form ATP
The carbon skeletons of pyruate molecules re-formed from lactate during exercise become oxidized for energy in CORI CYCLE
Lactate shuttling is the procedure in which lactate accumulation takes place fast twitch fibers for conversion into pyruate then into acetyl-coA and enters into cori cycle
Reaction taking place when pyruate preparing to enter the citric acid cycle by joining with vitamin B derivative aoenzyme A to form the 2-carbon compound acetyl-coA .2 H are been released transfer their electron to NAD
PYRUATE+NAD postive+coA AcetylecoA+co2+NADH+H
CITRIC ACID CYCLE
Carbon dioxide released in hydrolysis of 2 pyruate molecules
co2 H 2 molecules pyruate 2 4 2 molecules acetyl_coA 4 16 TOTAL 6 20
Triglycerides stored directly within the muscle fiber in close proximity to the mitochondria(more in slow twitch muscle fiber than fast twitch fiber)
Circulating triglycerides in lipoprotein complexes that lipoprotein lipase hydrolyses on the surface of a tissue capillary endothelium
Circulating free fatty acids mobilized from triglycerides in adipose tissue
ENERGY RELEASE FROM THE FAT
ABDOMINAL TISSUE GLYCEROL GLUCOSE
FATTY ACIDS INTRAMUCULAR TRIGLYCERIDE
FATTY ACIDE+ ALBUMIN FATTY ACIDS FFA
O2 ACETYL COA CITRIC ACID CYCLE ELECTRON TRANSPORT ATP
ADIPOCYTES:THE SITE OF FAT STORAGE AND MOBILIZATION
The harmones epinephrine,norepinephrine,glucagon,and growth hormone augement lipase activation and subsequent lipolysis and FFA mobilization from the adipose tissue . Plasma concentrations of these lipogenic hormones increase during exercise to provide active muscles with a continual supply of energy _rich subsatrate
An intracellular mediator ,adinosine 3,5 cyclic monophosphate activates lipase leading to break down
HARMONAL EFFECT
It is primarily the branched chain amino acids leucine,isoleucine,valine,glutamine and aspartate, plays a cotributory role as an energy substrate during endurance activities
The amino acids are first converted to a form that release energy
Deamination occurs in the liver to remove nitrogen from the amino acid
ENERGY RELEASE FROM THE PROTEIN
It is the interrelationship between carbohydrate,fat,and protien metabolism
FATs glycerol+fatty acids beta oxidation acetyl coA CARBOHYDRATES glycolysis release nucleotides,amino
sugars,glycolypids,glycoprotiens and lipids pyruate then release amino acids pyrimidines,lactate acetyle coA
PROTEINS amino acids deamination release ammonia,urea,urine after it theromineserine cysteinglycine enters into deamination in presense of alanine ant also enters to pyruate
From isoleucine leucine lysine tyrosine phenylalanine moves to acetyl coa and then to deamination
Entery in citricc acid cycle by arginine methonine asparaginephylalamine aspartate proline glutamate and then to deamination
THE METABOLIC MILL
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