ATP RE-SYNTHESIS

LESSON 2

ATP STORES ATP STORES ARE LOW IN OUR BODIES SO ATP HAS TO BE RE-MADE OR RE-

SYNTHESISED TO ALLOW ACTIVITY TO CONTINUE. THIS RE-SYNTHESIS IS ACHIEVED BY ONE OF THREE WAYS USING DIFFERENT

ENERGY SYSTEMS. THE SYSTEM USED DEPENDS ON THE INTENSITY AND DURATION OF THE ACTIVITY .

THESE SYSTEMS WILL NOT WORK IN ISOLATION TWO SYSTEMS CAN USUALLY WORK AT THE SAME TIME.

WE WILL LOOK AT EACH SYSTEM AND HOW IT PROVIDES ATP

PAGE 272 ONWARDS IN TEXT BOOK.

ENERGY FROM EACH OF THE 3 SYSTEMS IS USED TO CREATE THE REVERSE REACTION

ENERGY + ADP +P1 = ATP

THE ALACTIC / PHOSPHOCREATINE SYSTEM

IN ACTIVITY LASTING LONGER THAN 2 SECONDS, THE RE-SYNTHESIS OF ATP RELIES ON A SUBSTANCE CALLED PHOSPHOCREATINE. (PC)

PC LIKE ATP IS STORED IN OUR MUSCLES.

PHOSPHOCREATINE (PC)PHOSPHATE GROUP LOST = ENERGY RELEASED.

HOW PC RE-SYNTHESISES ATP

NET EFFECT PC + ADPCREATINE © REMAINS PRESENT FOR FUTURE

REACTIONS. THIS IS KNOWN AS A COUPLED REACTION

SINCE THE ENERGY RELEASED FROM PC IS COUPLED WITH THE ENERGY REQUIRED FOR ADP TO BE CONVERTED TO ATP

FURTHER CONSIDERATIONS DURING FLAT OUT EXERCISE SUCH AS SPRINTING (THAT LASTS

UNDER 10 SECONDS) ATP IS REPLENISHED BY THIS SYSTEM. SINCE NO 02 IS USED NO LACTIC ACID IS FORMED. THIS SYSTEM IS CALLED THE ALACTIC ANEAROBIC SYSTEM

SOMETIMES ABBREVIATED TO THE ATP – PC SYSTEM. MAIN USE = PROVIDES AN IMMEDIATE SOURCE OF ENERGY. WHEN HARD PHYSICAL ACTIVITY USES ALL THE PC UP A LIMIT OR

THRESHOLD IS REACHED – ATP IS THEN REGENERATED BY A PROCESS WHICH CONSUMES CARBOHYDRATES.

THIS PROCESS IS CALLED THE LACTIC ACID SYSTEM. THE THRESHOLD BETWEEN THE PC AND LACTIC ACID SYSTEM IS

CALLED THE ALACTIC – LACTIC THRESHOLD.

TRAINING CONSIDERATIONS A MAJOR FEATURE OF TRAINING FOR SPEED ENDURANCE AND

POWER ATHLETES WOULD BE ANEAROBIC WORK WITH THE PURPOSE OF DELAYING THE ALACTIC – LACTIC THRESHOLD.

THIS TYPE OF TRAINING WOULD CREATE BIOLOGICAL ADAPTATIONS WHICH WOULD ENABLE MUSCLE CELL SARCOPLASM TO CONTAIN MORE ATP AND CREATINE STORES TO ENSURE THE ATP –PC SYSTEM PROVIDES ENERGY FOR LONGER PERIODS OF TIME AT THE HIGHEST POSSIBLE RATE.

A REGULAR DAILY INTAKE SMALL AMOUNTS OF CREATINE IS THOUGHT TO INCREASE TOTAL MUSCLE CONTENT, AND PC STORES. IN THEORY THIS WOULD BE AVAILABLE FOR ALACTIC ANAEOBIC EXERCISE ALLOWING THE ATHLETE TO WORK AT A HIGHER INTENSITY BEFORE THE ALACTIC – LACTIC THRESHOLD IS REACHED.

EXTENSION WORK LOOKING AT PAGE 273 – WRITE IN

YOUR WORDS ADVANTAGES AND DISADVANTAGES OF THE ATP – PC SYSTEM. YOU CAN USE WHICH EVER FORMAT SUITS YOU BEST.

COPY KEY WORDS AND THE HOT TIP CONCERNING SARCOPLASM AND MITOCHONDRIA – WHAT HAPPENS INSIDE THEM?

LACTIC ACID SYSTEM ANOTHER ANAEROBIC SYSTEM FUEL USED HERE IS CARBOHYDRATES. A COMPOUND MADE OF CARBON

HYDROGEN AND OXYGEN THAT IS FOUND IN FOODS. CARBOHYDRATE – STORED IN THE MUSCLES AND LIVER AS GLYCOGEN. GLYCOGEN IS CONVERTED TO GLUCOSE BY THE ENZYME GLYCOGEN

PHOSPHORYLASE. GLUCOSE UNDERGOES A SERIES OF REACTIONS CALLED ANAERORBIC

GLYCOLYSIS WHICH IS ACTIVATED BY THE ENZYME PHOSPHOFRUCTOKINASE (PFK) UNTIL IT IS TURNED TO PYRUVIC ACID

DURING THIS PROCESS 2 MOLES ATP ARE RESYNTHESISED. DUE TO LACK OF O2 PYRUVIC ACID IS CONVERTED TO LACTIC ACID BY

THE ENZYME LACTATE DEHYDROGENASE. ALL OF THE ABOVE REACTIONS TAKE PLACE IN THE SARCOPLASM.

LACTIC ACID SYSTEM DIAGRAM

2 ATPPHOSPHOFRUCTOKINASE (PFK)

LACTATE DEHYDROGENASE

C6 H12 06

CONSIDERATIONS CARBS ARE STORED AS GLYCOGEN IN THE MUSCLE. LIKE THE

ATP-PC GLYCOGEN CAN BE USED TO RECREATE ATP RAPIDLY AGAIN BUT ONLY IN SMALL AMOUNTS.

FAST TWITCH MUSCLE FIBRES HOLD MORE GLYCOGEN THAN SLOW TWITCH WHICH IS ONE OF THE REASONS THAT FT CAN PRODUCE ENERGY MORE RAPIDLY THAN ST.

IT IS THE BREAKDOWN OF GLYCOGEN THAT PROVIDES THE ENERGY NEEDED TO REBUILD ADP INTO ATP. GLYCOLOSIS IS FAR MORE COMPLICATED THAN ATP – PC. IT NEEDS 10 ENZYMATIC REACTIONS FOR GLUCOSE TO BE BROKEN DOWN TO LACTIC ACID. THE THREE KEY ENZYMES ARE GPP, PFK AND LDH.

LACTIC ACID? AS LACTIC ACID ACCUMULATES MUSCLE FATIGUE AND PAIN OCCUR. THE PH LEVEL IN THE MUSCLE CELL INHIBITS ENZYME ACTION IN THE

MITOCHONDRIA WHICH NORMALLY PROMOTES THE CHANGE OF GLYCOGEN TO ENERGY.

THE EFFECT OF LACTIC ACID IS TO INHIBIT MUSCLE ACTION SO PERFORMANCE DETERIORATES.

EVENTS SUCH AS 400M RELY HEAVILY ON TH L.A SYSTEM (43-60 SECONDS OF FLAT OUT EFFORT).

AFTER EXERCISE EXTRA OXYGEN IS TAKEN IN TO REMOVE THE LACTIC ACID BY CHANGING IT BACK TO PYRUVIC ACID THIS IS KNOWN AS REPAYING THE OXYGEN DEBT – REMEMBER GCSE?

EXTENSION WORK

COPY REMAINING KEYWORDS ON PAGE 273

WRITE DOWN THE ADVANTAGES AND DISADVANTAGES ON THIS SYSTEM USING FIG 5.04 PG 274. WRITE IN YOUR OWN WORDS IN ANY FORMAT

THE AEROBIC SYSTEM RELIES ON THE PRESENCE OF 0XYGEN (02) TO BREAKDOWN

CARBOHYDRATES AND FATS COMPLETELY INTO CARBON DIOXIDE, WATER AND ENERGY.

THE ENERGY YEILD IS EXTREMELY HIGH ,ONE MOLECULE OF GLUCOSE YEILDS 36 MOLECULES OF ATP

2 36

AEROBIC PROCESS THE FIRST STAGE IS IDENTICAL TO THE LACTIC ACID SYSTEM.

THE DIFFERENCE IS WHEN OXYGEN IS AVAILABLE AND THE INTENSITY OF THE EXERCISE ALLOWS, THE PYRUVIC ACID IS MOVED INTO ANOTHER SET OF CHEMICAL REACTIONS INSTEAD OF BEING CONVERTED INTO LACTIC ACID.

CONSIDER THE 2 SYSTEMS LIKE BURNING WOOD. IF OXYGEN IS PRESENT THE WOOD WILL BURN WELL LEAVING A MASS OF ASH. IF THE FIRE IS STARVED OF OXYGEN THE WOOD WILL JUST BLACKEN AND TURN TO CHARCOAL. EVENTUALLY CARBOHYDRATE WILL COMPLETELY BE “BURNED” UP AND THE HARMLESS WASTE PRODUCTS WOULD BE REMOVED FROM THE BODY. IF FAT WAS USED MORE ENERGY WOULD BE GIVEN OFF – BUT MORE OXYGEN IS NEEDED TO FUEL THIS PROCESS.

AEROBIC SYSTEM

AEROBIC SYSTEM FROM THIS POINT ALL CHEMICAL REACTIONS OCCUR IN THE MUSCLE CELL

MITOCHONDRIA OFTEN REFERED TO AS THE POWER HOUSE OF MUSCLE CELLS.

PYRUVIC ACID IS TAKEN BY THE COENZYME ACETYL CoA INTO THE KREBS CYCLE (TRICARBOXCYLIC ACID OR CITRIC ACID CYCLE).

A FURTHER SET OF REACTIONS OCCUR FURTHER BREAKING DOWN THE CARBOHYDRATE COMPOUND.

THIS PROCESS OCCURS IN THE INNER FLUID FILLED MATRIX OF THE MITOCHONDRIA WHICH CONTAINS THE ENZYMES OF THE KREBS CYCLE.

ONCE A SERIES OF REACTIONS HAVE TAKEN PLACE – CARBON DIOXIDE AND HYDROGEN IONS ARE PRODUCED. 2 MOLES OF ATP ARE ALSO RESYNTHESISED.

IF FAT IS BEING USED AS FUEL IT ENTERS THE KREBS CYCLE AS FATTY ACIDS AND BETA OXIDATION OCCURS (TOTAL OF 34 ATP’S RELEASED FROM ACETYL COA ) AGAIN LOTS OF 02 NEEDED FOR THIS.

CO2 IS REMOVED VIA THE LUNGS AND THE HYDROGEN ATOMS ENTER THE NEXT SERIES OF CHEMICAL REACTIONS – THE ELECTRON TRANSFER CHAIN.

ELECTRON TRANSPORT STAGE OCCURS IN THE CRISTAE (FOLDS OF THE INNER MEMBRANE OF THE

MITOCHONDRIA ELECTRONS ARE REMOVED FROM THE HYDROGEN AND PASSED DOWN

AN ELECTRON CHAIN (ELECTRONS CHARGED WITH POTENTIAL ENERGY).

ELECTRONS ARE PASSED DOWN THE CHAIN PROVIDING ENERGY TO RESYNTHESISE 34 MOLES OF ATP.

THE HYDROGEN IS COMBINED WITH WATER TO PRODUCE WATER (H20) FINAL EQUATION C6 H1206 + 36PI +6O2 = 6CO2 + 36ATP + 6H20

CONSIDERATIONS AEROBIC ROUTE IS 18/19 TIMES

MORE EFFICIENT THAN THE ANEROBIC ROUTE.

MAJOR ADVANTAGE IS THAT THERE IS A MUCH LARGER SUPPLY OF ATP TO SUSTAIN STEADY STATE ACTIVITIES .

OVERLOAD TRAINING ENHANCES THE FUNCTIONAL CAPACITIES OF ALL 3 ENERGY SYSTEMS.

EXTENSION WORK

COPY KEY WORDS ON PAGE 275 WRITE OUT IN YOUR OWN WORDS

THE ADVANTAGES AND DISADVANTAGES OF THE AEROBIC SYSTEM.

Which predominate energy systems are being used in the following pictures