Respiration

Question 0

Respiratory substrate

Answer 0

• a substance that can be oxidised in respiration to release energy for the synthesis of ATP
• such as lipids (hydrolysed at glycolysis and link)
• proteins (hydrolysed link and krebs)

Question 1

Respiratory quotient

Answer 1

• carbs and protein similar
• fats nearly double ( mainly as more H’s)
• red blood cells& brains cell only use glucose
• heart about 70% lipids

Question 2

Alcoholic fermentation

Answer 2

• in yeast cells

- pyruvate -> pyruvate decarboxylase (loss of co2) -> ethanal -> ethanol dehydrogenase (NADred- NAD)

Question 3

Lactate fermentation

Answer 3

• normally in muscle cells
• if conc builds up in blood = nauseous
• hepatocytes turn it back into pyruvate
• requires O2
• pyruvate-> lactate (NADred-> NAD) using lactate dehydrogenase

Question 4

Why anaerobic respiration takes place

Answer 4

• O2 is final electron acceptor
• no O2
• electron carriers cant pass their electrons
• cant accept any more from NADred
• link & krebs cant take place

Question 5

Anaerobic respiration

Answer 5

• the partial oxidation of glucose to produce a small amount of energy
• it involves glycolysis followed by either lactate/ ethanol pathway

Question 6

ATP production from respiration

Answer 6

• 2 FADred = 4 ATP
• 10 NADred = 26 ATP
• per glucose = 34 ATP
• unlikely as
• some protons leak across membrane lowering proton motive force
• some ATP used to actively transport pyruvate into mitochondria
• some ATP to move NADred from cytoplasm to mitochondria

Question 7

Chemiosmosis evidence

Answer 7

• peter mitchell’s theory
• PH higher on the side of the membrane where ETC is shows active transport of H+
• membranes can produce ATP if not ETC as long as a PH gradient
• chemicals that stop H+ movement stop ATP production
• ie diniteophenol - carrier

Question 8

ATP synthesis

Answer 8

• e along ETC
• H+ from matrix to inter membrane space = PH gradient
• H+ through ATP synthase = ATP + H2O

Question 9

Chemiosmosis

Answer 9

• the way in which the diffusion if H+ down a concentration gradient across a membrane provides energy for ATP synthesis

Question 10

Electron transport chain (oxidative phosphorylation)

Answer 10

NADred -> e - q reductase - electron carrier-> H+ and oxidised NAD -> e +O2 + H+ -> H2O

Question 11

Electron transport chain

Answer 11

• a series of molecules that successfully gain and release electrons from coenzymes as the electron is passsed along it loses energy that is used to synthesis ATP
• inner memberane of the mitochondria

Question 12

Krebs cycle

Answer 12

• in the matrix
• oxaloacetate (4c) -> + acetyl-> citrate (6c) -> (lose co2 + NADred) -> 5c -> (lose co2 + NADred) -> 4c -> FADred + ADP-ATP -> (lose NADred) -> oxaloacetate

Question 13

Oxidative phosphorylation

Answer 13

• the production of ATP via the electron transport chain in a mitochondria using oxygen

Question 14

Substrate level phosphorylation

Answer 14

• the production of ATP directly from a reaction in the krebs cycle & glycolysis not involving the ETC

Question 15

The link reaction

Answer 15

• in the matrix
• pyruvate is decarboxylated and oxidised
• combines with CoA
• produces 2NADred and 2CO2

Question 16

Matrix

Answer 16

• the background material in a mitochondria

- where the link reaction & krebs cycle take place

Question 17

Cristae

Answer 17

• folds in the inner membrane of a mitochondria

- where the ETC takes place

Question 18

Mitochondria

Answer 18

• outer and inner membrane forming the envelope
• folded inner membrane = cristae
• ‘background material’ = the matrix

Question 19

Pyruvate

Answer 19

• product of glycolysis
• 3 carbon molecule
• start of anaerobic respiration
• moved into the mitochondria by active transport to the matrix

Question 20

Glycolysis

Answer 20

• in the cell cytoplasm
• produces 2ATP and 2NADred
• glucose -> + ATP -> Glucose-6-p -> isomerase -> fructose-6-p -> + ATP -> hexose1,6-bisphosphate-> 2x triose phosphate -> - 2ATP -2NADred -> 2x intermediate-> -2ATP -> 2x pyruvate

Question 21

ATP

Answer 21

• Adenosine triphosphate
• energy currency
• 3 phosphate groups
• 5 carbon ribose sugar
• nitrogen containing compound adenine
• removing 1 phosphate group = 30.5kj (hydrolysis with ATPase)
• releases energy quick, easy, the right size and the right place

Question 22

Respiration

Answer 22

• the release of chemical energy from glucose or other respiratory substrates by oxidation
• to mainly produce ATP
• in all living cells
• for active transport, metabolic reactions and protein synthesis