Importance of ATP Flashcards
(30 cards)
what is the matrix? (mitochondria)
(organic fluid) where the link reaction & Krebs cycle take place
What happens in the intermembrane space? (mitochondria)
electrochemical gradient. More
acidic / pH lower (acidic) /
build up of H+ ions
What is the Inner mitochondrial
membrane (folded as
cristae)?
-larger surface area for electron transport chains.
-Proton pumps, electron carriers and stalked particles (ATP
synthase) located here
What are starch grains? (chloroplasts)
polysaccharides of
glucose / alpha 1-4 (1-6) glycosidic
bonds (amylose and amylopectin)..
insoluble / osmotically inert
What happens in the stroma?
light independent reactions (LIR / Calvin cycle) = site of RUBISCO for
RuBP and CO2 fixation /
reduction of GP to TP /
regeneration of RuBp /
glucose synthesis
What happens in the thylakoid membrane?
light dependent reactions (LDR).
PSI, PSII, proton pumps, electron carriers & stalked particles.
What happens in the thylakoid space?
electrochemical gradient.
More acidic / pH lower (acidic) / build up of H+ ions
Distinguish between photophosphorylation and oxidative phosphorylation.
-Photophosphorylation occurs in the thylakoid membranes in the chloroplasts of green plants; ATP is synthesised using light energy (LDR = ATP and NADPH);
-Oxidative phosphorylation occurs at the inner mitochondrial membranes (cristae) in the presence of oxygen as the final e- acceptor; energy released from the oxidation of NADH and FADH at the start of the ETC (from oxidation of glucose) is used to synthesise ATP.
Where is ATP produced?
in the internal membranes of chloroplasts and mitochondria
What is the process of chemiosmosis?
Synthesis of ATP takes place by means of a flow of protons across these membranes down a
concentration gradient (electrochemical gradient) through the enzyme ATP synthase located in the stalked particles. This process is called chemiosmosis.
Where are proton pumps found in the mitochondria compared to the chloroplast?
mitochondria the proton pumps are found at the inner mitochondrial membrane whereas in a chloroplast they are found at the thylakoid membrane
How are protons transported in the mitochondria compared to the chloroplast?
Protons are actively transported from the matrix into the inter-
membrane space in the mitochondrion, where-as protons are pumped from the stroma into the thylakoid space in a chloroplast
How does the electrochemical gradient form in the mitochondria compared to the chloroplast?
-The electrochemical gradient forms in the inter-membrane space in a
mitochondrion and the thylakoid space in a chloroplast
-This gradient causes the pH here to be more acidic
What happens as protons diffuse along their conc grad?
As protons diffuse along their -concentration gradient through a proton channel in a ATP stalked particle, energy is released for the synthesis of ATP
-This is catalysed by ATP Synthase
What is the production of ATP called in the mitochondrion compared to the chloroplast?
-The production of ATP this way in the mitochondrion is called oxidative phosphorylation
In a chloroplast it is called
photophosphorylation
In animals such as humans, there are two types of adipose (fat) tissue, white and brown.
Babies have large quantities of brown adipose tissue but levels normally fall in adults.
The cells in brown adipose tissue have a very large number of mitochondria and are provided with a very rich blood supply. The mitochondria produce a protein, called thermogenin, which makes the inner membrane more permeable to protons.
Use your knowledge of respiration to explain the effect of thermogenin in the mitochondria.
• Protons diffuse / flow down conc. gradient;
• From inter membrane space )into matrix of mitochondrion;
• No proton gradient, protons do not flow through stalked particles/ ATP synthetase;
• No / very little ATP produced;
: Earre alosuass or s,
Large amounts of sugars and fats broken down;
What is the roles of water in respiration compared to photosynthesis?
r- H2O produced when O2
(final electron acceptor)
reacts with 4H+ and 4e-
p- 2H2O splits to O2, 4H+
and 4e- by photolysis
What is the role of high energy e- in respiration compared to photosynthesis?
r- Released from oxidation
of NADH and FADH2
p- Released from chlorophyll
a in the reaction centre of
PSII and PSI)
What is the role of redox reactions in respiration compared to photosynthesis?
r- NAD and FAD get reduced,
as respiratory substrates
(e.g. triose phosphate) get
oxidised
p- NADP is reduced in non-cyclic
photophosphorylation (LDR)
and then oxidised in the Calvin
cycle. As Glycerate-3-
phosphate is reduced to
What are the number of proton pumps in respiration vs photosynthesis?
r- 3 (FADH2 only activated 2 proton pumps)
p- 1
Where are electron carriers and ATP synthase in respiration vs photosynthesis?
R -Found in the inner mitochondrial
membrane (cristae)
p -Found in the thylakoid membranes
mitochondrial membrane (cristae)
Where do protons build up in respiration vs photosynthesis?
r- Protons pumped into Intermembrane space
p- Protons pumped into thylakoid space
Where is the Electrochemical
gradient generated by
chemiosmosis in respiration vs photosynthesis?
r- Gradient between matrix
and intermembrane space
p- Gradient between
stroma and thylakoid space
What co-enzymes are involved in respiration vs photosynthesis?
r- NAD, FAD, Coenzyme A
p- NADP
