METABOLISM AND BIOCHEMISTRY Flashcards
(23 cards)
Describe work
a change in the arrangement of matter
anabolism
synthesis of molecules-energy stored
catabolism
break down of molecules-energy released
what is gibbs free energy
the energy available to do useful work
gibbs free energy formula
(delta H) - T(delta S)
-ve and +ve gibbs free energy
-ve = spontaneous \+ve = needs energy to occur
what is entropy a measure of
disorder and the amount of unusable energy
How is ATP turned into ADP
By hydrolysis where a phosphate comes off
ATP -> ADP does this produce energy
yes
ADP -> ATP does this produce energy
no, requires energy
1 mol of ATP undergoing hydrolysis…
releases 30.5kJ/mol due to braking of P-P bond
redox reactions relative to energy release
oxidation= liberates energy reduction= stores energy
what are the forms of NAD and how are they made
NAD+ by oxidation (low energy)
NADH by reduction (high energy)
basic pathway of aerobic cellular respiration
glucose glycolysis krebs cycle e- transport chain 6CO2 + energy
outline Glycolysis
occurs in the cytosol, glucose is converted into 2 pyruvate molecules. This yields ATP and H+ from pyruvates are carried to mitochondria by NAD for electron transport chain
yield of Glycolysis
2 ATP in
4 ATP & 2NADH out
outline the Krebs cycle
If O2 is present, pyruvate enters the Krebs cycle. The molecule is changed
2C to 4C to 6C to 4C(regenerated)
yield of Krebs cycle
1 pyruvate in
4 NADH, 1 FADH2, 1 ATP out
outline e- transport chain
occurs in cristae of mitochondria
oxidises NADH and FADH
this constant down shift of energy is what produces 30-32 (up to 36) ATP and ends with O2 being converted to waste H2O at the end
outline anaerobic respiration
pyruvate does not enter the mitochondria and only 2 ATP is produced.
ethanol bi product in plants
lactic acid in animals
what is metabolism
the sum of all biochemical reactions in an organism. Cells are in permanent disequilibrium due to constant input
enzymes speed up rate but do not change
delta G
What is feedback regulation
where the products of a reaction can be used as a signal to decide whether the reaction should continue
positive feedback = keep going
negative feedback = stop
regulation allows for versatility of catabolism and anabolism
