Mitochondria Biochemistry Flashcards
Which energies are involved in the body?
Movement = mechanical
Metabolism = chemical
Heat generation = chemical
Nerve transmission = chemical
What does all energy production depend on in the body?
ATP
What are the components of ATP?
Adenine
Ribose
3x Pi
What are the bonds between ribose and phosphate group?
Phosphate ester bond
What bond is between the phosphate groups?
Phospho-anhydride bond
What happens in hydrolysis of ATP?
ATP —-> ADP + energy
Do hydrolysis of ATP require or release energy?
Release
Why are anhydride molecules high energy?
Very susceptible to hydrolysis thus cleavage
Release lots of energy
What is Gibbs free energy equation at RTP?
ΔG = ΔH - TΔS
What do acetic anhydrides react with OH to form?
Esters
What is acetic anhydrides bond type?
Stable BUT unstable
Why is acetic anhydride that bond type?
Breakdown rapidly BUT release good supply of energy
Negative value = breakdown spontaneous
What is ATP hydrolysis directly linked to?
Endergonic reactions
How does linking happen?
Through shared intermediate
One product used as reactant in 2nd reaction
How is ATP involved in NaK?
ATP transfers 1xPi to pump Phosphorylated pump unstable = changes shape = releases Na+ K+ bind to pump = Pi removed = protein unable to change shape = releases K+
What is the site if ATP production?
Mitochondria
Describe e- transport chain
Located in mitochondria
Complexes I, II, III, IV + V
What are the e- carriers?
NADH
NAD
What happens in e- chain?
NAD+ + H+ + 2e- ⇌ NADH
FAD + 2H+ +2e- ⇌ FADH
GENERATES e-
What is the energy from e- transport chain used to do?
Pump H+ into intermembrane space
Describe what happens at proton pump
Electrical + chemical gradient of H+ between intermembrane space + matrix
Through ATP synthase
ADP —-> ATP
What happens in glycolysis?
Glucose phosphorylated
What is glucose phosphorylated to?
Glucose-6-phosphate
Phospho-glucose-isomerase rearranges glucose into fructore-6-phosphate
Pi added from ATP
Fructose splits = dihydroxyacetone phosphate + glyceraldehyde-3-phosphate
DHAP —-> glyceraldehyde-3-phosphate
2 reactions occur simultaneously
GA3P oxidised
NAD+ reduced to NADH + H+
1,3 biphosphoglycerate donates 1 Pi to ADP = 3-phosphoglycerate + ATP
Phosphoglycerate loses H2O = phosphoenolpyruvate
PEP donates Pi to ADP = ATP
PEP converted to pyruvate
How many ATP is needed to phosphorylate glucose?
1
What happens after glycolysis if O2 present?
Pyruvate oxidised = CO2 + ATP
NADH pass e- onto ETC
= regenerates NAD+ for glycolysis
What happens after glycolysis if no O2 present?
NADH donates e- to acceptor molecule
DOESN’T make ATP BUT regenerate NAD+
When is lactic acid produced?
Anaerobic respiration
How is lactic acid produced?
NADH accumulates due to O2 shortage
Needs to be removed
= pyruvate takes up 2xH from NADH
= lactate + NAD+
