Energy Reactions

Question 1

Metabolism Defintion

Answer 1

The set of processes which derive energy and raw materials from food stuffs and use them to support repair, growth and activity of bodies tissues to sustain life

Question 2

Catabolism Pathways:
What is its function?
Oxidative or reductive?
Using free energy or releasing?

Answer 2

Breaks down larger molecules into smaller intermediary metabolites
EXERGONIC - Release Free Energy
OXIDATIVE - Release H atoms (reducing power)

Question 3

Anabolic pathways:
Function?
EXERGONIC or ENDERGONIC ?
Oxidative or Reductive

Answer 3

Synthesise larger cellular components from intermediary metabolites
ENDERGONIC = Uses energy released from CATABOLISM (ATP)
REDUCTIVE - Uses H released in CAtabolism often from NADH, NADPH or FADH2

Question 4

Gibbs FREE ENERGY = USEFUL ENERGY

For EXERGONIC AND ENDERGONIC Reactions is the free energy value positive or negative?

Answer 4

NEGATIVE for EXERGONIC
POSITIVE for ENDERGONIC (uses free energy)

Question 5

Relationship between EXERGONIC and ENDERGONIC reactions

Answer 5

They are coupled
EXERGONIC reactions provide energy for ENDERGONIC reactions

Question 6

Importance of Metabolism

Answer 6

Obtain energy for cell function (ATP)
Produce IMprotant metabolites needed in synthesis of cell components
Organic precursor molecules
Biosynthetic reducing power (NADPH, NADH, FADH2)

Question 7

High energy of hydrolysis bond of ATP. Where is this bond and why is it useful?

Answer 7

Between the terminal phosphate group and 2nd phosphate.
REleases lots of free energy when the bond is Hydrolysed

Question 8

ATP is not a store of free energy

Answer 8

It is a carrier of free energy

Question 9

OIL RIG

Answer 9

Oxidation Is Loss of ELectrons or (LOSS of H)
Reduction Is Gain of ELectrons or (GAIN OF H)

Question 10

H-Carrier Molecules examples

Answer 10

NAD+ / NADH
NADP+ / NADPH
FAD / FADH2
Are cofactors/coenzymes

Question 11

Role of H-carriers

Answer 11

Metabolic Pathways cease without them
Needed in ATP Production (NADH and FADH2)
Biosynthesis (NADPH)
Levels of oxidised + reduced form of carriers stay same so conversion between 2 is necessary

Question 12

REDOX Reations

Answer 12

Oxidation and reduction reaction coupled
Oxidation reaction (loss of H) releases energy to drive ATP synthesis needed for a reduction reaction (addition of H)

Question 13

ATP is stable

Answer 13

Needs catalysts/enzymes present

Question 14

How much ATP does the body contain

Answer 14

About 250g

Question 15

Creatine Phosphate Role

Answer 15

A Reserve of High energy store that’s can be immediately utilised in times where metabolic activity needs to be rapidly increased (skeletal muscles)

Question 16

Creatine Phosphate Formation

Answer 16

Needs ENZYME CREATINE KINASE
Creatine + ATP <—-> Creatine Phosphate + ADP

When [ATP] HIGH more Creatine Phosphate, builds up energy store
When [ATP] LOW reaction reverses to produce ATP rapidly

Question 17

What is a high energy signal?

Answer 17

Its a substance that signals that the cell has adequate energy levels for its immediate needs.

Question 18

Low Energy Signals, what are they?

Answer 18

They signal that the cell doesn’t have enough energy for its cellular needa

Question 19

Examples of High Energy Signals

Answer 19

ATP
NADH
NADPH
FADH2

Question 20

Examples of Low Energy SIgnals

Answer 20

ADP
AMP
NAD+
NADP+
FAD

Question 21

Creatinine

Answer 21

Metabolite of Creatine and Creatine phosphate
Creatinine has no function so is excreted in urine

Question 22

Creatinine clinical importance

Answer 22

Daily creatinine excretion is proportional to creatine in muscle so indicates skeletal muscle mass

High blood creatinine and low urine creatinine = reduced kidney function