Respiration Flashcards
What does metabolism refer to?
All the reactions of the organism.
What sort of pathway is respiration?
It is a metabolic pathway which is controlled by enzymes (catabolic). Energy rich macromolecules are broken down i.e. glucose and fatty acids to release energy: some is trapped as chemical energy in ATP and some is released as heat energy.
What high energy bonds are broken down?
C-C
C-H
C-OH
What happens when the high energy bonds are broken down?
Lower energy bonds are formed and the difference is released and used to attach a phosphate group to ADP to produce ATP.
What is oxidative phosphorylation?
It’s the energy from the oxidation and reduction reactions to make ATP which is released as a transfer of electrons along a chain of electron carrier molecules.
Where does oxidative phosphorylation occur?
On the inner membrane of the mitochondria in aerobic respiration
What is substrate phosphorylation?
It occurs when phosphate groups are transferred from donor molecules or when enough energy is released so that ATP combined to a phosphate group.
What is aerobic respiration?
It’s the release of large amounts of energy made available as ATP from the breakdown of molecules with oxygen as a terminal electron acceptor.
What is anaerobic respiration?
The breakdown of molecules in the absence of oxygen releasing little energy making a small amount of ATP by substrate level phosphorylation.
What energy does respiration provide for?
Condensation reactions of ADP to ATP, energy for this reaction comes from the chemical energy stored in glucose.
What is each stage of respiration catalysed by?
A specific enzyme
Catalyisation of enzymes are examples of what sort of reaction?
Oxidation (loss of H)
Reduction (gain of H)
What do you coenzymes do?
They assist are the enzymes in oxidation and reduction reactions. Co enzymes are continuously cycled.
What are the co-enzymes used in respiration?
NAD
FAD
Co- enzyme A
What happens if the coenzymes are reduced?
They are use in the final stage of respiration (oxidative phosphorylation) which produces ATPThey are use in the final stage of respiration (oxidative phosphorylation) which produces ATP
What is NAD used in?
Glycolysis, link reaction, Krebs cycle, anaerobic respiration (lactate pathways)
What is NAD?
Dinucleotide.
Derived from vitamin B.
Niacinamide.
NAD (OX) NADH (RED)
What is coenzyme A?
It derives from vitamin B
What is CoA used in?
It’s used to transfer product of glycolysis into the mitochondria for the link reaction. It carries the acetyl groups created through oxidation during the link reaction onto the Krebs cycle.
What is FAD?
Derives from B2.
Made from adenine, ribose, two phosphate groups.
FAD –> FADH
Where is FAD used?
In the Krebs cycle
What are the four stages of aerobic respiration?
Glycolysis, link reaction, Krebs cycle, oxidative phosphorylation
Where does glycolysis occur?
In the cytoplasm
Where does the link reaction occur?
In the mitochondrial matrix (pyruvate diffuses from the cytoplasm to the matrix)
Where does the Krebs cycle occur?
In the mitochondrial matrix
Where does oxidative phosphorylation occur?
On the inner mitochondrial membrane (Cristal)
What does glycolysis generate?
Pyruvate, ATP, NADH
What does LR generate?
Acetyle CoA
What does KC generate?
CO2, NADH, FADH
What does oxidative phosphorylation generate?
ATP from ADP + Pi
Glycolysis facilitate what pathways?
Aerobic and anaerobic
Where does glycolysis occur?
It occurs in the cytoplasm as glucose is too large to pass through the membrane, the enzymes are found in the cytoplasm.
What process is glycolysis?
Anaerobic
What does glycolysis produce?
2 pyruvate, 2 NADH, 2 (NET) ATP and heat energy
Use a flow chart to show glycolysis?
Glucose (6C) –> Hexose biphosphate —> 2 Triose phosphate (TP)(3C) –> 2GP (3C) –> 2 pyruvate (3C)
Why is glucose is phosphorylated?
It lowers the activation energy for the enzyme controlled reactions. It becomes polar so less likely to diffuse out of the cell.
Show the equation for glycolysis?
Glucose + 2NAD + 2ADP +2Pi –> 2 Pyruvate + 2NADH + 2ATP + heat energy
Show the equation for LR?
pyruvate + CoA + NAD –> Acetyl CoA + CO2 + NADH
What does one glucose molecule in the link reaction produce?
2NADH, 2 Acetyl CoA, 2CO2
What two enzymes are used in the link reaction?
Dehydrogenase and decarboxylase