respiration😏😏 Flashcards
where is the electron transport chain in respiration
inner mitochondrial membrane
why does aerobic respiration yield fewer molecules of ATP than theoretical maximum
- some ATP used to actively transport pyruvate into mitochondria
- some ATP used to actively transport H+ from NADH formed in glycolysis into mitochondria
- not all NADH used to feed into ETC, some released as heat
why does anaerobic respiration yield less ATP than aerobic respiration
- in anaerobic, glycolysis occurs producing 2 net ATP
- only substrate level phosphorylation occurs
- no oxygen available as final electron acceptor
- oxidative phosphorylation does not occur
- pyruvate used to regenerate NAD for glycolysis
why are parasites that live in the blood of mammals adapted to respire anaerobically despite oxygen being carried in the blood
- parasites have little access to oxygen
- not much oxygen dissolved in plasma
- oxygen is combined with Hb
why can the anaerobic pathway in animals be reversed but not in yeast
in animals
- pyruvate converted to lactate
- can be reversed as no other products
- lactate dehydrogenase to reverse
in yeast
- pyruvate converted to ethanal and co2
- cannot be reversed as co2 lost
why is lactate converted to glucose in hepatotcytes rather than in the respiring cells where it is produced
- hepatocytes can tolerate lactate
- hepatocytes have enzymes to metabolise lactate
what might happen if the liver did not break down insulin after it was used
- blood glucose would fall below normal
- insulin would continue converting glucose to glycogen for storage
- cannot generate enough ATP as not enough glucose
- coma/death
consequences for liver metabolism if person has high alcohol intake
- build up of fatty acids results in fat deposits in liver cells
- ornithine cycle cannot occur
- build up of lactate kills liver cells
where in liver cells is excess NADH reoxidised
inner mitochondrial membrane
why is respiration rate low at 6 degrees
- not enough kinetic energy for ESC
- respiration uses enzymes
why does respiration stop at 90 degrees
-enzymes denatured
in the anaerobic yeast pathway what is the hydrogen acceptor
ethanal
why is the anaerobic pathway important for plant cells
- allows some ATP to be produced in glycolysis
- ATP needed for metabolic processes such as active transport
where in aerobic respiration is co2 produced
krebs cycle and link reaction
why is there more respiration at a higher temperature
- enzymes involved
- more kinetic energy for ESC
why would wet pea seeds respire more than dry pea seeds
- reactions need to take place in water
- enzymes and substrate can move in water
- soaked seeds need more ATP
benefits of anaerobic respiration
- ATP still produced
- allows glycolysis to continue
role of coenzymes in a leaf cell
- CoA transports acetyle to Krebs cycle
- NAD accepts H
- NADH carries electrons to ETC
- NADH carries H+ for oxidative phosphorylation
- NADPH carries H to Calvin cycle
explain role of ATP in cell
- transfers energy
- phosphates removed by hydrolysis
- energy released for active transport
- energy released in small packets
- ADP can attach phosphate during respiration
process carried out by cristae
oxidative phosphorylation
describe how an endotherm prevents body temp decreasing when external temp decreases
- skin thermoreceptors stimulated
- impulse sent to hypothalamus
- vasoconstriction of arterioles to reduce heat loss
- prevents heat loss by convection
- increased metabolism to generate heat
- adrenaline released which causes shivering
describe anaerobic respiration in animals
- pyruvate converted to lactate
- pyruvate accepts H
- H from NADH
- catalysed by lactate dehydrogenase
- no O2 to act as final electron acceptor so no ETC
suggest how seals are adapted to respire for a long time underwater
- lungs have high vital capacity
- lower metabolic rate
- more glycolysis
- tolerates lactate
- plenty of Hb
why is ethanol considered a primary metabolite of yeast
ethanol produced by yeast as metabolic waste
factors that may limit maximum size of yeast population
- pH falls too low
- high ethanol concentration damages yeast
- sugar concentration falls too low
why does yeast use up monosaccharide first, then disaccharide and then trisaccharide
- mono can enter glycolysis without being broken down first
- di must be hydrolysed first
- tri must be hydrolysed twice
- enzymes for hydrolysis only produced when needed
how could emphysema result in fatigue
- less ventilation
- less o2 reaching cells for aerobic respiration
- less ATP produced
how could type 2 diabetes result in fatigue
- not enough glucose uptake into cells
- not enough glucose for respiration
- glucose not converted to glycogen
how could a weak/ irregular heartbeat cause fatigue
- lower blood pressure
- less o2 for aerobic respiration
- less glucose for respiration
- less ATP produced
why do people with chronic fatigue have a poor immune response
- little ATP for antibody production
- little ATP for B cell mitosis
when measuring oxygen production of an aquatic plant with apparatus, how to supply co2
-bubble in co2
seaweeds that live deep in water contain a high amount of pigments other than chlorophyll how is this an advantage
- lower light intensity deep in water
- not all wavelengths can penetrate water
- these pigments absorb wavelengths that can penetrate deeper water
what is the fate of triose phosphate in the calvin cycle
- used to regenrate RuBP
- so cycle can continue for CO2 fixation
- formation of glucose and lipids
what effect does an increase in oxygen concentration have on photosynthesis
- decrease rate of photosynthesis
- oxygen binds to rubisco so less available for carbon dioxide
- less co2 fixation
- less GP produced
- less RuBP formed
some plants use PEP carboxylase to fix carbon dioxide, why do these not show photorespiration
-PEP carboxylase cannot bind to oxygen
how to control co2 concentration in greenhouse
burn paraffin
what happens if a plant is only exposed to green light
- chlorophyll cannot absorb green light
- little photosynthesis
- little CO2 taken up
- some CO2 produced in respiration
- pH decreases due to the CO2
name the type of reaction when atp is converted to adp
hydrolysis
why does the graph of rate and concentration eventually level off for active transport
active transport carrier proteins become saturated
how does calculating a mean improve an experiment
reduces random error (uncertainty)
how does using a colorimeter with more dp improve an experiment
increase resolution
Describe the production of ATP by substrate-level phosphorylation in different stages of respiration with reference to the number of ATP molecules produced
- during glycolysis 4 ATP produced, 2 used up, so 2 net ATP
- triose phosphate converted to pyruvate
- 1 ATP produced per krebs cycle
- 5 carbon compound converted to oxaloacetate
suggest a role for coenzyme other than CoA in the link reaction
NAD reduced by hydrogen
conclusion about respiration if RQ 0.95
mostly carbohydrates
conclusion about respiration if RQ 0.85
more fats respired
conclusion about respiration if RQ 1.3
more anaerobic respiration
when is ATP made during glycolysis
- triose phosphate is converted to pyruvate by dephosphorylation
- 2 ATP produced per TP so 4 ATP produced
when is NADH made in glycolysis
- triose phosphate oxidised to pyruvate
- one NADH per TP so 2 NADH made
when is ATP used in glycolysis
- glucose phosphprylated to hexose bisphosphate
- 2 ATP needed
when is NADH produced in link reaction
- pyruvate converted to acetate
- one NADH produced
when is ATP made in krebs cycle
- 5 carbon compound converted to oxaloacetate
- 1 ATP per krebs cycle
when is NADH made in the krebs cycle
- 1 NADH made when citrate is converted to 5 carbon compound
- 2 NADH made when 5C compound is converted to oxaloacetate
- 3 NADH made per krebs cycle
when is FADH2 made
- in krebs cycle when 5C compound is converted to oxaloacetate
- one is made
when is CO2 made in the krebs cycle
- when citrate is converted to 5 carbon compound
- when 5 carbon compound converted to oxaloacetate
- 2 per krebs cycle
in the ETC in mitochondria, what is formed once the final electron is accepted
water
in animal anaerobic respiration what is the hydrogen acceptor
pyruvate
what is produced as a result of animal anaerobic respiration
lactate
NAD
describe anaerobic respiration in microorganisms
- glycolysis
- pyruvate is decarboxylated to ethanal, producing CO2
- ethanal is reduced to ethanol, this uses alcohol dehydrogenase, and produces NAD
products of anaerobic respiration in microorganisms
CO2
ethanol
NAD
what happens to lactate produced in anaerobic respiration
- can be oxidised to pyruvate (requires O2 known as oxygen debt)
- can be converted to glycogen
