Unit 3.1 - The importance of ATP Flashcards
what are the 3 major processes which need an imput of free energy
-mechanical work(musclecontraction)
- active transport of molecules + ions
- Biosynthesis
what 2 sources does free energy come from
- oxidation of food molecules (glucose) - respiration
- Trapping light energy - photosynthesis
what is the main carrier of free energy?
adenosine triphosphate
what is adenosine triphosphate made up of
- phosphate group
- ribose (pentose sugar)
- adenine (organic base)
how does ATP produce free energy
ATP is hydrolysed (dephosphorylation) to ADP + Pi
(= energy)
how is ATP produced
condensation reaction (phosphorylation) ADP + Pi
when does phosphorylation occur
during oxidation of food, and light harvesting
what enzyme catalysis the reaction where ATP is hydrolysed to ADP
ATP synthase
define ATP
ATP is the universal energy currency. It supplies energy for ALL reactions in ALL cells across the spectrum of life
what are the advantages of having ATP as a source of energy
- soluble ∴ easily transported across membrane
- provides immediate source of energy(easily hydrolysed)
- needs only 1 enzyme
- inert
where is ATP produced
atp synthesis occurs on the internal membrane of mitochondria and chloroplasts
how is ATP synthesised
- ATP synthase phosphorylates ADP to form ATP as protons flow through it
where do protons flow in the mitochondria
-from intermembrane space –into matrix
-across inner membrane
where do protons flow in the chloroplast
-from thylakoid space
-into stroma
-across thylakoid membrane
define chemiosmosis
-The synthesis of ATP through movement of protons down an electrical chemical gradient (across semi-permeable membrane)
- by ATP synthase
