respiration Flashcards
what would you control eg yeast experiment
volume of yeast suspension
species of yeast
age of yeast
volume of glucose
concentration of glucose
calculating rate of respiration
calculate rate of colour change
rate is inversely proportional to the time taken for colour change
1/time
rate of respiration is directly proportional to the rate of colour change / use as a proxy measurement
increase of temperature on respiration
as temperature increases, rate of respiration increases
higher temperature so enzymes have more kinetic energy
increased likelihood of successful collisions between enzymes and substrates eg increased production of NADH
so more hydrogens removed
until optimum temperature
then rate of respiration decreases as enzymes become denatured as hydrogen bonds holding tertiary structure of enzyme break
advantage of anaerobic respiration
despite no oxygen being available, glycolysis can still continue
to produce ATP so organism still have energy
glycolysis
glucose phosphorylated to glucose phosphate (2 ATP)
lysis of glucose phosphate to 2 triose phosphates
oxidation of triose phosphate - NADH
substrate-linked phosphorylated of triose phosphate to form pyruvate
4 - ATP
NET 2 ATP
role of pyruvate in anaerobic respiration
pyruvate reduced to lactate
so NAD regenerated
so glycolysis can continue
so ATP still produced
carbon count in molecules
glucose - 6
triose phosphate - 3
pyruvate - 2
acetyl coA - 6
then 5 then 4
NADH and FADH in oxidative phosphorylation
NADH and FADH2 - donate electrons to electron transport chain in the inner mitochondrial membrane
electrons then passed along from one protein carrier to the next (in the electron transport chain)
releasing energy as they move along the electron transport chain
this energy is captured in the form of an electrochemical / proton / energy gradient
glucose and ATP
as glucose concentration increases, so does the amount of ATP
this is due to more glucose being present for use in glycolysis
this produces greater pyruvate and ATP
how is pyruvate converted to lactate
glycolysis produces 2 pyruvate molecules and 2 NADH
each pyruvate takes two hydrogen atoms from NADH to produce lactate
why is the production of lactate beneficial
NAD is oxidised so it can be regenerated for further use so available for glycolysis
name substances formed from pyruvate
CO2, water, ATP, NADH / NADH2
explain why the dissociation of lactate has an effect on enzymes in muscle cells
dissociation of lactic acid lowers pH
leading to increased acidity
affecting hydrogen bonds - tertiary structure - reaction speed of enzymes
advantage for lactate being oxidised in muscle cells
lactate and pyruvate are energy sources
muscles have an immediate energy or ATP supply near to the site where it’s needed
substrate-level phosphorylation vs oxidative phosphorylation for producing ATP
substrate-level phosphorylation
1. phosphate added to ADP directly
2. doesnt involve chemiosmosis
3. does not involve ATP synthase
4. does not involve ETC
5. does not use reduced co-factors
6. occurs under aerobic and anaerobic conditions
oxidative phosphorylation
1. phosphate not added to ADP directly
2. involves chemiosmosis
3. involves ATP synthase
4. involves ETC
5. uses NADH / FADH2
6. occurs under aerobic conditions
