ATP and chemiosmosis Flashcards
what are autotrophs
plants that trap light energy converting it to chemical energy of organic molecules
what are heterotrophs
animas, fungi, bacteria that consue plants
What does ATP stand for and what is it made from and what is it
Adenosine Triphosphate. made from -a nitrogenous base (adenine) -ribose (pentose sugar) - three phosphate groups It is a phosphorylated nucleotide, belongs to the nucleic acids (like DNA)
How is ATP made
ATP is made from ADP and inorganic phosphate using energy from energy-releasing reactions e.g respiration. ATP synthetase catalyses this process
what is the reaction called if energy is used
endergonic reaction
How is ATP broken down
ATP is broken down into ADP and inorganic phosphate, releasing the energy contained within the bond
ATPase catalyses this process.
what is the reaction called if the energy is released?
exergonic reaction
why do we need ATP
active tranposrt, replication of DNA. muscle contraction, sodium potassium pumps, reaboption in PCT.
What happens when ATP is hydrolysed into ADP
energy is released by breaking the terminal phosphate bond. It is an immediate source of energy for metabolism.
What is ATP described as
A universal energy currency because it supplies energy to all cells for all chemical reactions
How is ATP made
ATP proudced across inner membrane of mitochondria and thylakoid mmebrane of chloroplasts.
process is called phosphorylation
ATP is a phosphorylated nucleotide
there is 3 types of phosphorylation in respiration and photosynthesis
- substrate phosphorylation in respiration
- Oxidative phosphorylation (needs oxygen) in aerobic respiration
-Photophosphorylation (needs light) takes place in chloroplasts of plants
what does OIL RIG stand for
Oxidation is loss of electrons and protons from hydrogen atoms but gains oxygen
Reduction is the gain of electrons and protons from hydrogen atoms but also is loss of oxygen
In respiration and photosynthesis, how are electrons used?
in respiration and photosynthesis, there are electron transport chains that are formed on the inner membranes of mitochondria and chloroplasts. the electrons are used as a source of energy to pump protons (postively charged hydrogen ions) across the membrane.
where do the hydrogen atoms come from in respiration
they come from oxidation of substances within respiration and they need an enzyme - dehydrogenase and hydrogen acceptors take the hydrogen to the electron transport chain
What are hydrogen acceptors
co-enzymes (NAD, FAD), that work with the enzyme dehydrogenase that removes hdyrgoen from the substrates involved in respiration.
hydrogen is passed to the hydrogen acceptors
as they remove the hydrogen the substrate is oxidised and the acceptor is reduced
they pass electrons from the hydrogen to the electron transport chain which creates the enrgy needed for the proton pump
What is substrate phosphorylation
the energy is needed to convert ADP to ATP comes from the conversion of one substrate to another
what is oxidative phosphorylation
takes place in the mitochondria on the inner membrane. from one substrate to antoher NAD is becomes reduced by gaining hydrogen atom. and electrons are used as energy in chemiosmosis to make ATP
what is photophosphorylation
takes place in the chloroplasts in green plants during the light dependent reaction of photosynthesis
where is ATP produced
the electron transport chain in the inner membrane of mitochondria and chloroplasts.
hydrogen removed from substrates used in respiration using hte enzyme dehydrogenase. it is then picked up by hydrogen acceptors NAD, FAD…
substrate then becomes oxidised and hydrogen acceptor becomes reduced
What is the generation of ATP
chemiosmosis - cells use the enrgy released by ‘falling electrons’ in the electron transport chain to pump hydrogen ions across membrane. this uses the ATP synthetase
What happens every time NAD passes its hydrogen on to the electron transport chain
3 ATP molecules would be made through chemiosmosis
what happens every time FAD passes its hydrogen on to the electron transport chain
2 ATP molecules would be made through chemiosmosis
what do the reduced NAD and FAD do when they reach to the inner membrane of the mitochondrion
pass their hydrogen atoms onto cytochome carriers found. Then the atoms are split into electrons and protons. (hydrogen ions)
As the elctrons are passed between the cytochrome electron carriers, energy is released.
What forms the electrochemical gradient
The energy released when the elctrons pass between the cytochrome electron carriers, in which is used to pump protons via specialised proton pumps from the matrix into the intermembrane space forming the electrochemical gradient
What can you find on the stalked granules on the inner membrane
ATP synthetase, the protons flow down their concentration gradient through channels in the stalked granules back out into matrix. the energy released is used to ‘turn’ the enzyme and so phosphorylate ADP into ATP.
what do the used protons do
they combine with electrons and oxygen atoms to form water
