respiration topic 5 Flashcards
(35 cards)
what is respiration?
a chemical process required to release energy from glucose, which is used to synthesise ATP
what does ATP stand for?
adenine triphosphate
what is ATP made of?
adenine, ribose, 3 phosphate groups
where is the energy stored in ATP?
in the third bond
how is ATP made?
photophosphorylation, oxidative phosphorylation, substrate level phosphorylation
when does photophosphorylation occur?
during photosynthesis
when does oxidative phosphorylation occur?
in the mitochondria during aerobic respiration
when does substrate level phosphorylation occur?
when the phosphate comes from a donor molecule
what is the order for the stages of respiration?
glycolysis
link reaction
krebs cycle
oxidative phosphorylation
where does glycolysis occur?
in the cytoplasm
what happens during glycolysis?
glucose (6c) uses 2ATP-2ADP to form glucose phosphate
this then splits into 2 triose phosphate (3c)
this then splits into 2 pyruvate (3c) by breaking down 2ATP into 2 ADP, and NAD into NADH
what are the products from glycolysis?
2 pyruvate, 2 NADH and a net gain of 2 ATP
what are the summarised stages of glycolysis?
phosphorylate glucose to glucose phosphate using ATP, produce triose phosphate, oxidation of triose phosphate into pyruvate
what is needed before the Link Reaction can occur?
pyruvate and NADH need to be actively transported from the cytoplasm into the mitochondrial matrix
where does the Link Reaction occur?
mitochondrial matrix
what happens during the Link Reaction?
pyruvate (3c) is oxidised to form acetate (2c) (releases 1 carbon dioxide, NAD into NADH)
coenzyme A added to form acetyl co enzyme A (2c)
what are the summarised stages of the Link Reaction
pyruvate is oxidised to form acetate, picks up hydrogen to become reduced NAD,acetate combines with co enzyme A to produce acetyl co enzyme A
how many times does the Link reaction occur for every glucose molecule?
twice
what are the products of the Link Reaction?
2 acetyl co enzyme A, 2 carbon dioxide, 2 reduced NAD
where does the Krebs cycle occur?
in the mitochondrial matrix
what happens during the Krebs Cycle?
acetyl co enzyme A (2c) reacts with oxoloacetate (4c) to release co enzyme A
this produces citrate (6c) which enters the Krebs cycle
2 carbon dioxide are lost, atp and pi are transferred into atp, fad is tranferred into reduced fad, and 3 nad are transferred into 3 reduced nad
what are the products from 2 cycles?
2 co enzyme A, 2 oxoloacetate, 4 carbon dioxide, 2 atp, 6 reduced nad, 2 reduced fad
where does oxidative phosphorylation occur?
in the mitochondrial inner membrane (cristae)
what are the stages of oxidative phosphorylation?
1) hydorgen atoms released from NADH and FADH as they are oxidised to form NAD and FAD
2) hydrogen atoms split into protons and electrons
3) electrons move down the electron transport chain and lose energy at each carrier
4) energy used by electron carriers to pump protons from the mitochondrial matrix into the intermembrane space
5) concentration of protons higher in the intermembrane space than the mitochondiral matrix
6) this forms an electrochemical gradient
7) protons move down the electrochemical gradeint into the mitochondiral matrix via ATP synthase
8) this synthesises ATP from ADP and inorganic phosphate
9) ATP production from movement of hydrogen ions across a membrane= chemiosmosis
10) in the mitochondrial matrix at the end of the transport chain, protons/electrons/oxygen combine to form water
11) oxygen is the final electron acceptor
