3.5.2 Respiration Flashcards
3.5.2 Respiration (50 cards)
what is it meant by the term phosphorlation
the addition of the phosphate group to a molecule
what are the two main types of phosporilation found in respiration
Oxidative phosphorylation – occurs during aerobic respiration where ATP is formed in the electron transport system. “Oxidative” refers to the energy of oxidation/reduction reactions, not oxygen gas.
normally done with the aid of channel or carrier proteins
Substrate level phosphorylation – the formation of ATP by the direct transfer of a phosphate group from a reactive intermediate to ADP
normally done when ATP — ADP
normally does not require Pi as it is found on the substraite
what is respiration
A series of enzyme controlled reactions which produce chemical energy in the form of ATP from organic molecules (mainly glucose)
It can be done aerobically (with oxygen) or anaerobically (without oxygen)
give the general equation for respiration
C6H12O6 + 6O2 —> 6CO2 + 6H2O + (energy)
what is the definition of a co-enzyme
Coenzymes bind with a specific enzyme or substrate, helping to catalyze a reaction. Coenzymes transfer a chemical group (like hydrogen) from one molecule to another.
waht are the three main co-enzymes in respiration and what do they do
NAD (nicotinamide adenine dinucleotide)
transfer hydrogen from one molecule to another (so can oxidise or reduce a molecule)
FAD (flavine adenine dinucleotide)
transfer hydrogen from one molecule to another
Coenzyme A
transfers acetate between molecules
what is it called when you remove a hydorgen
Dehydrogenation: The removal of hydrogen (using dehydrogenase enzymes). Can also therefore be called oxidation.
caould also say deprotonation
what is it called when you remove a carbon to form CO2
Decarboxylation: Removal of carbon (in the form of COOH, using decarboxylase enzymes) to form carbon dioxide
what are the four stages of respiration
glycolysis
the link reaction
krebs cycle
the electron transport chain
where does glycolysis take place , and why
Glycolysis happens in the cytoplasm because the glucose is too large to pass through the outer membrane of the mitochondria
where does the link reaction take place
the matrix of mitochondria
draw out the glycolysis chain reaction and then list the steps
also list the compounds made during these steps
glucose —> glucose phosphate —> hexose biphosphate —> 2x triose phosphate —> 2x pyruvate
1) Glucose is phosphorylated using a phosphate from the hydrolysis of ATP (from a supply in the cytoplasm). giving 1 mol of ATD and one mole of Glucose phosphate
2) phosphorilation from ATP, making hexose biphosphate and ADP
3) lysis of hexose biphosphate making 2 x triose phosphate
4) two triose phosphate is dehydogenated forming two pyruvates
4)B) 2 NAD are then reduced forming reduced NAD , when triose phosphate —-> pyruvates
4)C) 4 ADP and Pi are substraite level phosporliated to produce 4 ATP
what is the net production of ATP in glycolysis
2
you make 4 but loose two to make those two
does glycolysis need oxygen
no it can be done during anerobically or arobically however is a anarobic PROCESS
draw out a mitochondria
https://studymind.co.uk/notes/the-structure-of-mitochondria/
can the link reaction be undergon in arobic respiration and anarobic respiration
no it can only be undergone during aerobic respiration
describe the stages of the link reaction
show the order of compounds made
pyruvate (3c)—> acetate(2c) —–> acetyle CoA (2c)
1) Pyruvate is decarboxylated (carbon removed) in the form of carbon dioxide One carbon is removed
while also reducing 1 NAD to reduced NAD (dehydrogenation)
the end product is acetate (2c)
2) acetate combinds with Coenzyme-A to produce acetyle CoA
remember 2 Acetyle CoA are made per glucose molecules
no ATP is made during this stage
where does the Krebs cycle take place
in the matrix of the mitochondria
what are the stages of the krebs cycle
acetyleCOa drops off CoA and combines with Oxaloacetate to produce citrate (6c)
Citrate –> decarboxilation (produces CO2) —-> NAD to reduced NAD —> decarboxilation (produces CO2) —-> NAD to reduced NAD —-> ADP +Pi goes to ATP —-> FAD to reduced FAD —-> NAD to reduced NAD —–> oxaloacetate
why is reduced FAD produced rather than reduced NAD
The amount of energy released in this part of the Kreb’s cycle is not enough to drive the reduction of NAD to NADH and so FAD is used.
Reduced FAD does not contain as much energy as reduced NAD.
what are the two processes of the electron transport chain
1) Electron Transport Chain
2) Chemiosmosis
where does the electron transport chain take place
in the inner membraine of the mitocondria
what are the steps of the electron transport chain
1) Hydrogen atoms are released from reduced NAD and reduced FAD. They become oxidised to NAD and FAD
The hydrogen atoms split into protons (H+) and electrons (e-)
2)The electrons move along the electron transport chain from one electron protein carrier to another in a series of redox reactions. which is made up of three electron carriers
They lose energy at each carrier
3) The energy that is lost as the electrons moved along the electron transport chain is used by electron carriers .
Electron carriers pump protons from the matrix into the intermembrane space
4) The concentration of protons is now higher in the intermembrane space than in the matrix
This forms an electrochemical gradient (a concentration gradient of ions)
5) Protons can now move down the electrochemical gradient back across the inner membrane and into the matrix
This happens via ATP synthase
This movement drives the synthesis of ATP from ADP and inorganic phosphate (Pi)
6)Protons can now move down the electrochemical gradient back across the inner membrane and into the matrix
This happens via ATP synthase
This movement drives the synthesis of ATP from ADP and inorganic phosphate (Pi)
what is chemiosmosis
Chemiosmosis is the movement of ions across a semipermeable membrane bound structure, down their electrochemical gradient. An important example is the formation of adenosine triphosphate (ATP) by the movement of hydrogen ions (H+) across a membrane during cellular respiration or photosynthesis.
